[v9] riscv: compat: Add COMPAT Kbuild skeletal support

[PATCH V9 00/20] riscv: compat: Add COMPAT Kbuild skeletal support

guoren@kernel.org posted 20 patches 4 years, 3 months ago

Diff against v8
Download series mbox

arch/arm64/Kconfig                            |   4 -
arch/arm64/include/asm/compat.h               |  91 +------
arch/arm64/include/asm/unistd.h               |   1 +
arch/mips/Kconfig                             |   5 -
arch/mips/include/asm/compat.h                |  41 +--
arch/mips/include/asm/unistd.h                |   2 +
arch/mips/include/uapi/asm/fcntl.h            |  30 +--
arch/parisc/Kconfig                           |   4 -
arch/parisc/include/asm/compat.h              |  45 +---
arch/parisc/include/asm/unistd.h              |   1 +
arch/powerpc/Kconfig                          |   5 -
arch/powerpc/include/asm/compat.h             |  50 +---
arch/powerpc/include/asm/unistd.h             |   1 +
arch/riscv/Kconfig                            |  19 ++
arch/riscv/Makefile                           |   9 +
arch/riscv/configs/rv32_defconfig             | 135 ----------
arch/riscv/include/asm/compat.h               | 129 ++++++++++
arch/riscv/include/asm/csr.h                  |   7 +
arch/riscv/include/asm/elf.h                  |  50 +++-
arch/riscv/include/asm/mmu.h                  |   1 +
arch/riscv/include/asm/pgtable.h              |  13 +-
arch/riscv/include/asm/processor.h            |   6 +-
arch/riscv/include/asm/syscall.h              |   1 +
arch/riscv/include/asm/thread_info.h          |   1 +
arch/riscv/include/asm/unistd.h               |  11 +
arch/riscv/include/asm/vdso.h                 |   9 +
arch/riscv/include/uapi/asm/unistd.h          |   2 +-
arch/riscv/kernel/Makefile                    |   3 +
arch/riscv/kernel/compat_signal.c             | 243 ++++++++++++++++++
arch/riscv/kernel/compat_syscall_table.c      |  19 ++
arch/riscv/kernel/compat_vdso/.gitignore      |   2 +
arch/riscv/kernel/compat_vdso/Makefile        |  78 ++++++
arch/riscv/kernel/compat_vdso/compat_vdso.S   |   8 +
.../kernel/compat_vdso/compat_vdso.lds.S      |   3 +
arch/riscv/kernel/compat_vdso/flush_icache.S  |   3 +
.../compat_vdso/gen_compat_vdso_offsets.sh    |   5 +
arch/riscv/kernel/compat_vdso/getcpu.S        |   3 +
arch/riscv/kernel/compat_vdso/note.S          |   3 +
arch/riscv/kernel/compat_vdso/rt_sigreturn.S  |   3 +
arch/riscv/kernel/entry.S                     |  18 +-
arch/riscv/kernel/process.c                   |  37 +++
arch/riscv/kernel/ptrace.c                    |  87 ++++++-
arch/riscv/kernel/signal.c                    |  13 +-
arch/riscv/kernel/sys_riscv.c                 |   6 +-
arch/riscv/kernel/vdso.c                      | 105 +++++---
arch/riscv/kernel/vdso/vdso.S                 |   6 +-
arch/s390/Kconfig                             |   3 -
arch/s390/include/asm/compat.h                |  99 +------
arch/s390/include/asm/unistd.h                |   1 +
arch/sparc/Kconfig                            |   5 -
arch/sparc/include/asm/compat.h               |  61 ++---
arch/sparc/include/asm/unistd.h               |   1 +
arch/x86/Kconfig                              |   4 -
arch/x86/include/asm/compat.h                 | 104 ++------
arch/x86/include/asm/unistd.h                 |   1 +
fs/open.c                                     |  24 ++
fs/read_write.c                               |  16 ++
fs/stat.c                                     |   2 +-
fs/sync.c                                     |   9 +
include/asm-generic/compat.h                  | 113 ++++++++
include/linux/compat.h                        |  68 +++++
include/uapi/asm-generic/fcntl.h              |  23 +-
include/uapi/asm-generic/unistd.h             |   4 +-
init/Kconfig                                  |   4 +
mm/fadvise.c                                  |  11 +
mm/readahead.c                                |   7 +
tools/include/uapi/asm-generic/fcntl.h        |  21 +-
tools/include/uapi/asm-generic/unistd.h       |   4 +-
68 files changed, 1205 insertions(+), 698 deletions(-)
delete mode 100644 arch/riscv/configs/rv32_defconfig
create mode 100644 arch/riscv/include/asm/compat.h
create mode 100644 arch/riscv/kernel/compat_signal.c
create mode 100644 arch/riscv/kernel/compat_syscall_table.c
create mode 100644 arch/riscv/kernel/compat_vdso/.gitignore
create mode 100644 arch/riscv/kernel/compat_vdso/Makefile
create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.S
create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.lds.S
create mode 100644 arch/riscv/kernel/compat_vdso/flush_icache.S
create mode 100755 arch/riscv/kernel/compat_vdso/gen_compat_vdso_offsets.sh
create mode 100644 arch/riscv/kernel/compat_vdso/getcpu.S
create mode 100644 arch/riscv/kernel/compat_vdso/note.S
create mode 100644 arch/riscv/kernel/compat_vdso/rt_sigreturn.S

Expand all Fold all

[PATCH V9 00/20] riscv: compat: Add COMPAT Kbuild skeletal support

Posted by guoren@kernel.org 4 years, 3 months ago

From: Guo Ren <guoren@linux.alibaba.com>

Currently, most 64-bit architectures (x86, parisc, powerpc, arm64,
s390, mips, sparc) have supported COMPAT mode. But they all have
history issues and can't use standard linux unistd.h. RISC-V would
be first standard __SYSCALL_COMPAT user of include/uapi/asm-generic
/unistd.h.

The patchset are based on v5.17-rc8, you can compare rv64-compat
v.s. rv32-native in qemu with following steps:

 - Prepare rv32 rootfs & fw_jump.bin by buildroot.org
   $ git clone git://git.busybox.net/buildroot
   $ cd buildroot
   $ make qemu_riscv32_virt_defconfig O=qemu_riscv32_virt_defconfig
   $ make -C qemu_riscv32_virt_defconfig
   $ make qemu_riscv64_virt_defconfig O=qemu_riscv64_virt_defconfig
   $ make -C qemu_riscv64_virt_defconfig
   (Got fw_jump.bin & rootfs.ext2 in qemu_riscvXX_virt_defconfig/images)

 - Prepare Linux rv32 & rv64 Image
   $ git clone git@github.com:c-sky/csky-linux.git -b riscv_compat_v8 linux
   $ cd linux
   $ echo "CONFIG_STRICT_KERNEL_RWX=n" >> arch/riscv/configs/defconfig
   $ echo "CONFIG_STRICT_MODULE_RWX=n" >> arch/riscv/configs/defconfig
   $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ rv32_defconfig
   $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ Image
   $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ defconfig
   $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ Image

 - Prepare Qemu:
   $ git clone https://gitlab.com/qemu-project/qemu.git -b master linux
   $ cd qemu
   $ ./configure --target-list="riscv64-softmmu riscv32-softmmu"
   $ make

Now let's compare rv64-compat with rv32-native memory footprint with almost the same
defconfig, rootfs, opensbi in one qemu.

 - Run rv64 with rv32 rootfs in compat mode:
   $ ./build/qemu-system-riscv64 -cpu rv64 -M virt -m 64m -nographic -bios qemu_riscv64_virt_defconfig/images/fw_jump.bin -kernel build-rv64/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0

QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
OpenSBI v0.9
[    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv64-unknown-linux-gnu-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.37) #96 SMP Tue Dec 28 21:01:55 CST 2021
[    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
[    0.000000] Machine model: riscv-virtio,qemu
[    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
[    0.000000] printk: bootconsole [sbi0] enabled
[    0.000000] efi: UEFI not found.
[    0.000000] Zone ranges:
[    0.000000]   DMA32    [mem 0x0000000080200000-0x0000000083ffffff]
[    0.000000]   Normal   empty
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000080200000-0x0000000083ffffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x0000000083ffffff]
[    0.000000] SBI specification v0.2 detected
[    0.000000] SBI implementation ID=0x1 Version=0x9
[    0.000000] SBI TIME extension detected
[    0.000000] SBI IPI extension detected
[    0.000000] SBI RFENCE extension detected
[    0.000000] SBI v0.2 HSM extension detected
[    0.000000] riscv: ISA extensions acdfhimsu
[    0.000000] riscv: ELF capabilities acdfim
[    0.000000] percpu: Embedded 17 pages/cpu s30696 r8192 d30744 u69632
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15655
[    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
[    0.000000] Dentry cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
[    0.000000] Inode-cache hash table entries: 4096 (order: 3, 32768 bytes, linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] Virtual kernel memory layout:
[    0.000000]       fixmap : 0xffffffcefee00000 - 0xffffffceff000000   (2048 kB)
[    0.000000]       pci io : 0xffffffceff000000 - 0xffffffcf00000000   (  16 MB)
[    0.000000]      vmemmap : 0xffffffcf00000000 - 0xffffffcfffffffff   (4095 MB)
[    0.000000]      vmalloc : 0xffffffd000000000 - 0xffffffdfffffffff   (65535 MB)
[    0.000000]       lowmem : 0xffffffe000000000 - 0xffffffe003e00000   (  62 MB)
[    0.000000]       kernel : 0xffffffff80000000 - 0xffffffffffffffff   (2047 MB)
[    0.000000] Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved, 0K cma-reserved)
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[    0.000000] rcu: Hierarchical RCU implementation.
[    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
[    0.000000] rcu:     RCU debug extended QS entry/exit.
[    0.000000]  Tracing variant of Tasks RCU enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] riscv-intc: 64 local interrupts mapped
[    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
...
Welcome to Buildroot
buildroot login: root
# cat /proc/cpuinfo
processor       : 0
hart            : 0
isa             : rv64imafdcsuh
mmu             : sv48

# file /bin/busybox
/bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
# ca[   78.386630] random: fast init done
# cat /proc/meminfo
MemTotal:          53076 kB
MemFree:           40264 kB
MemAvailable:      40244 kB
Buffers:             236 kB
Cached:             1560 kB
SwapCached:            0 kB
Active:             1700 kB
Inactive:            516 kB
Active(anon):         40 kB
Inactive(anon):      424 kB
Active(file):       1660 kB
Inactive(file):       92 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:             0 kB
SwapFree:              0 kB
Dirty:                 0 kB
Writeback:             0 kB
AnonPages:           444 kB
Mapped:             1188 kB
Shmem:                44 kB
KReclaimable:        952 kB
Slab:               5744 kB
SReclaimable:        952 kB
SUnreclaim:         4792 kB
KernelStack:         624 kB
PageTables:          156 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:       26536 kB
Committed_AS:       1748 kB
VmallocTotal:   67108863 kB
VmallocUsed:         652 kB
VmallocChunk:          0 kB
Percpu:               80 kB
#

 - Run rv32 with rv32 rootfs:
   $ ./build/qemu-system-riscv32 -cpu rv32 -M virt -m 64m -nographic -bios qemu_riscv32_virt_defconfig/images/fw_jump.bin -kernel build-rv32/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0

QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
OpenSBI v0.9
[    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv32-buildroot-linux-gnu-gcc.br_real (Buildroot 2021.11-201-g7600ca7960-dirty) 10.3.0, GNU ld (GNU Binutils) 2.36.1) #7 SMP Tue Dec 28 21:02:21 CST 2021
[    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80400000
[    0.000000] Machine model: riscv-virtio,qemu
[    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
[    0.000000] printk: bootconsole [sbi0] enabled
[    0.000000] efi: UEFI not found.
[    0.000000] Zone ranges:
[    0.000000]   Normal   [mem 0x0000000080400000-0x0000000083ffffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000080400000-0x0000000083ffffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000080400000-0x0000000083ffffff]
[    0.000000] SBI specification v0.2 detected
[    0.000000] SBI implementation ID=0x1 Version=0x9
[    0.000000] SBI TIME extension detected
[    0.000000] SBI IPI extension detected
[    0.000000] SBI RFENCE extension detected
[    0.000000] SBI v0.2 HSM extension detected
[    0.000000] riscv: ISA extensions acdfhimsu
[    0.000000] riscv: ELF capabilities acdfim
[    0.000000] percpu: Embedded 12 pages/cpu s16600 r8192 d24360 u49152
[    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15240
[    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
[    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, linear)
[    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, linear)
[    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
[    0.000000] Virtual kernel memory layout:
[    0.000000]       fixmap : 0x9dc00000 - 0x9e000000   (4096 kB)
[    0.000000]       pci io : 0x9e000000 - 0x9f000000   (  16 MB)
[    0.000000]      vmemmap : 0x9f000000 - 0x9fffffff   (  15 MB)
[    0.000000]      vmalloc : 0xa0000000 - 0xbfffffff   ( 511 MB)
[    0.000000]       lowmem : 0xc0000000 - 0xc3c00000   (  60 MB)
[    0.000000] Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss, 9516K reserved, 0K cma-reserved)
[    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
[    0.000000] rcu: Hierarchical RCU implementation.
[    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
[    0.000000] rcu:     RCU debug extended QS entry/exit.
[    0.000000]  Tracing variant of Tasks RCU enabled.
[    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
[    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
[    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
[    0.000000] riscv-intc: 32 local interrupts mapped
[    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
...
Welcome to Buildroot
buildroot login: root
# cat /proc/cpuinfo
processor       : 0
hart            : 0
isa             : rv32imafdcsuh
mmu             : sv32

# file /bin/busybox
/bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
[   79.320589] random: fast init done
# cat /proc/meminfo
MemTotal:          52176 kB
MemFree:           41012 kB
MemAvailable:      42176 kB
Buffers:             644 kB
Cached:             2724 kB
SwapCached:            0 kB
Active:             3128 kB
Inactive:            752 kB
Active(anon):         40 kB
Inactive(anon):      516 kB
Active(file):       3088 kB
Inactive(file):      236 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:             0 kB
SwapFree:              0 kB
Dirty:                 4 kB
Writeback:             0 kB
AnonPages:           556 kB
Mapped:             2172 kB
Shmem:                44 kB
KReclaimable:        656 kB
Slab:               3684 kB
SReclaimable:        656 kB
SUnreclaim:         3028 kB
KernelStack:         312 kB
PageTables:           88 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:       26088 kB
Committed_AS:       2088 kB
VmallocTotal:     524287 kB
VmallocUsed:          12 kB
VmallocChunk:          0 kB
Percpu:               60 kB
#

 Some conclusions:
 - kernel statics:
   64: Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved)
   32: Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss,  9516K reserved)
   rv32 better than rv64:                  1%               22%           17%          13%        19%         11%
   The code size is very similar, but data size rv32 would be better.

 - rv32 kernel runtime KernelStack, Slab... are smaller,
   rv64: MemTotal: 53076 kB,        MemFree: 40264 kB
   rv32: MemTotal: 52176 + 2048 kB, MemFree: 41012  + 2048 kB
   rv32 better than rv64:       2%                         6%

   (Because opensbi problem, we could add another 2MB for rv32.)
   Overall in 64MB memory situation, rv64-compat is 6% worse than rv32-native
   at memory footprint. If the userspace memory usage increases, I think
   the gap will be further reduced.

Changes in v9:
 - Fixup rv32 call rv64 segment fault
 - Ready for 5.18

Changes in v8:
 - Enhanced elf_check_arch with EI_CLASS
 - Fixup SR_UXL doesn't exist in CONFIG_32BIT
 - Add Tested-by with Heiko
 - Update qemu compile tips with upstream repo

Changes in v7:
 - Re-construct compat_vdso/Makefile
 - Fixup disable COMPAT compile error by csr.h's macro.
 - Optimize coding convention for lo/hi in compat.h

Changes in v6:
 - Rebase on linux-5.17-rc5
 - Optimize hw capability check for elf
 - Optimize comment in thread_info.h
 - Optimize start_thread with SR_UXL setting
 - Optimize vdso.c with direct panic

Changes in v5:
 - Rebase on linux-5.17-rc2
 - Include consolidate the fcntl patches by Christoph Hellwig
 - Remove F_GETLK64/F_SETLK64/F_SETLKW64 from asm/compat.h
 - Change COMPAT_RLIM_INFINITY from 0x7fffffff to 0xffffffff
 - Bring back "Add hw-cap detect in setup_arch patch" in v1

Changes in v4:
 - Rebase on linux-5.17-rc1
 - Optimize compat_sys_call_table implementation with Arnd's advice
 - Add reviewed-by for Arnd. Thx :)
 - Remove FIXME comment in elf.h
 - Optimize Cleanup duplicate definitions in compat.h with Arnd's advice

Changes in v3:
 - Rebase on newest master (pre linux-5.17-rc1)
 - Using newest qemu version v7 for test
 - Remove fcntl common modification
 - Fixup SET_PERSONALITY in elf.h by Arnd
 - Fixup KVM Kconfig
 - Update Acked-by & Reviewed-by

Changes in v2:
 - Add __ARCH_WANT_COMPAT_STAT suggested
 - Cleanup fcntl compatduplicate definitions
 - Cleanup compat.h
 - Move rv32_defconfig into Makefile
 - Fixup rv64 rootfs boot failed, remove hw_compat_mode_detect
 - Move SYSVIPC_COMPAT into init/Kconfig
 - Simplify compat_elf_check

Christoph Hellwig (3):
  uapi: simplify __ARCH_FLOCK{,64}_PAD a little
  uapi: always define F_GETLK64/F_SETLK64/F_SETLKW64 in fcntl.h
  compat: consolidate the compat_flock{,64} definition

Guo Ren (17):
  kconfig: Add SYSVIPC_COMPAT for all architectures
  fs: stat: compat: Add __ARCH_WANT_COMPAT_STAT
  asm-generic: compat: Cleanup duplicate definitions
  syscalls: compat: Fix the missing part for __SYSCALL_COMPAT
  riscv: Fixup difference with defconfig
  riscv: compat: Add basic compat data type implementation
  riscv: compat: Re-implement TASK_SIZE for COMPAT_32BIT
  riscv: compat: syscall: Add compat_sys_call_table implementation
  riscv: compat: syscall: Add entry.S implementation
  riscv: compat: process: Add UXL_32 support in start_thread
  riscv: compat: Add elf.h implementation
  riscv: compat: Add hw capability check for elf
  riscv: compat: vdso: Add COMPAT_VDSO base code implementation
  riscv: compat: vdso: Add setup additional pages implementation
  riscv: compat: signal: Add rt_frame implementation
  riscv: compat: ptrace: Add compat_arch_ptrace implement
  riscv: compat: Add COMPAT Kbuild skeletal support

 arch/arm64/Kconfig                            |   4 -
 arch/arm64/include/asm/compat.h               |  91 +------
 arch/arm64/include/asm/unistd.h               |   1 +
 arch/mips/Kconfig                             |   5 -
 arch/mips/include/asm/compat.h                |  41 +--
 arch/mips/include/asm/unistd.h                |   2 +
 arch/mips/include/uapi/asm/fcntl.h            |  30 +--
 arch/parisc/Kconfig                           |   4 -
 arch/parisc/include/asm/compat.h              |  45 +---
 arch/parisc/include/asm/unistd.h              |   1 +
 arch/powerpc/Kconfig                          |   5 -
 arch/powerpc/include/asm/compat.h             |  50 +---
 arch/powerpc/include/asm/unistd.h             |   1 +
 arch/riscv/Kconfig                            |  19 ++
 arch/riscv/Makefile                           |   9 +
 arch/riscv/configs/rv32_defconfig             | 135 ----------
 arch/riscv/include/asm/compat.h               | 129 ++++++++++
 arch/riscv/include/asm/csr.h                  |   7 +
 arch/riscv/include/asm/elf.h                  |  50 +++-
 arch/riscv/include/asm/mmu.h                  |   1 +
 arch/riscv/include/asm/pgtable.h              |  13 +-
 arch/riscv/include/asm/processor.h            |   6 +-
 arch/riscv/include/asm/syscall.h              |   1 +
 arch/riscv/include/asm/thread_info.h          |   1 +
 arch/riscv/include/asm/unistd.h               |  11 +
 arch/riscv/include/asm/vdso.h                 |   9 +
 arch/riscv/include/uapi/asm/unistd.h          |   2 +-
 arch/riscv/kernel/Makefile                    |   3 +
 arch/riscv/kernel/compat_signal.c             | 243 ++++++++++++++++++
 arch/riscv/kernel/compat_syscall_table.c      |  19 ++
 arch/riscv/kernel/compat_vdso/.gitignore      |   2 +
 arch/riscv/kernel/compat_vdso/Makefile        |  78 ++++++
 arch/riscv/kernel/compat_vdso/compat_vdso.S   |   8 +
 .../kernel/compat_vdso/compat_vdso.lds.S      |   3 +
 arch/riscv/kernel/compat_vdso/flush_icache.S  |   3 +
 .../compat_vdso/gen_compat_vdso_offsets.sh    |   5 +
 arch/riscv/kernel/compat_vdso/getcpu.S        |   3 +
 arch/riscv/kernel/compat_vdso/note.S          |   3 +
 arch/riscv/kernel/compat_vdso/rt_sigreturn.S  |   3 +
 arch/riscv/kernel/entry.S                     |  18 +-
 arch/riscv/kernel/process.c                   |  37 +++
 arch/riscv/kernel/ptrace.c                    |  87 ++++++-
 arch/riscv/kernel/signal.c                    |  13 +-
 arch/riscv/kernel/sys_riscv.c                 |   6 +-
 arch/riscv/kernel/vdso.c                      | 105 +++++---
 arch/riscv/kernel/vdso/vdso.S                 |   6 +-
 arch/s390/Kconfig                             |   3 -
 arch/s390/include/asm/compat.h                |  99 +------
 arch/s390/include/asm/unistd.h                |   1 +
 arch/sparc/Kconfig                            |   5 -
 arch/sparc/include/asm/compat.h               |  61 ++---
 arch/sparc/include/asm/unistd.h               |   1 +
 arch/x86/Kconfig                              |   4 -
 arch/x86/include/asm/compat.h                 | 104 ++------
 arch/x86/include/asm/unistd.h                 |   1 +
 fs/open.c                                     |  24 ++
 fs/read_write.c                               |  16 ++
 fs/stat.c                                     |   2 +-
 fs/sync.c                                     |   9 +
 include/asm-generic/compat.h                  | 113 ++++++++
 include/linux/compat.h                        |  68 +++++
 include/uapi/asm-generic/fcntl.h              |  23 +-
 include/uapi/asm-generic/unistd.h             |   4 +-
 init/Kconfig                                  |   4 +
 mm/fadvise.c                                  |  11 +
 mm/readahead.c                                |   7 +
 tools/include/uapi/asm-generic/fcntl.h        |  21 +-
 tools/include/uapi/asm-generic/unistd.h       |   4 +-
 68 files changed, 1205 insertions(+), 698 deletions(-)
 delete mode 100644 arch/riscv/configs/rv32_defconfig
 create mode 100644 arch/riscv/include/asm/compat.h
 create mode 100644 arch/riscv/kernel/compat_signal.c
 create mode 100644 arch/riscv/kernel/compat_syscall_table.c
 create mode 100644 arch/riscv/kernel/compat_vdso/.gitignore
 create mode 100644 arch/riscv/kernel/compat_vdso/Makefile
 create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.S
 create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.lds.S
 create mode 100644 arch/riscv/kernel/compat_vdso/flush_icache.S
 create mode 100755 arch/riscv/kernel/compat_vdso/gen_compat_vdso_offsets.sh
 create mode 100644 arch/riscv/kernel/compat_vdso/getcpu.S
 create mode 100644 arch/riscv/kernel/compat_vdso/note.S
 create mode 100644 arch/riscv/kernel/compat_vdso/rt_sigreturn.S

-- 
2.25.1

Re: [PATCH V9 00/20] riscv: compat: Add COMPAT Kbuild skeletal support

Posted by Palmer Dabbelt 4 years, 3 months ago

On Tue, 22 Mar 2022 07:39:43 PDT (-0700), guoren@kernel.org wrote:
> From: Guo Ren <guoren@linux.alibaba.com>
>
> Currently, most 64-bit architectures (x86, parisc, powerpc, arm64,
> s390, mips, sparc) have supported COMPAT mode. But they all have
> history issues and can't use standard linux unistd.h. RISC-V would
> be first standard __SYSCALL_COMPAT user of include/uapi/asm-generic
> /unistd.h.
>
> The patchset are based on v5.17-rc8, you can compare rv64-compat
> v.s. rv32-native in qemu with following steps:
>
>  - Prepare rv32 rootfs & fw_jump.bin by buildroot.org
>    $ git clone git://git.busybox.net/buildroot
>    $ cd buildroot
>    $ make qemu_riscv32_virt_defconfig O=qemu_riscv32_virt_defconfig
>    $ make -C qemu_riscv32_virt_defconfig
>    $ make qemu_riscv64_virt_defconfig O=qemu_riscv64_virt_defconfig
>    $ make -C qemu_riscv64_virt_defconfig
>    (Got fw_jump.bin & rootfs.ext2 in qemu_riscvXX_virt_defconfig/images)
>
>  - Prepare Linux rv32 & rv64 Image
>    $ git clone git@github.com:c-sky/csky-linux.git -b riscv_compat_v8 linux
>    $ cd linux
>    $ echo "CONFIG_STRICT_KERNEL_RWX=n" >> arch/riscv/configs/defconfig
>    $ echo "CONFIG_STRICT_MODULE_RWX=n" >> arch/riscv/configs/defconfig
>    $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ rv32_defconfig
>    $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ Image
>    $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ defconfig
>    $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ Image
>
>  - Prepare Qemu:
>    $ git clone https://gitlab.com/qemu-project/qemu.git -b master linux
>    $ cd qemu
>    $ ./configure --target-list="riscv64-softmmu riscv32-softmmu"
>    $ make
>
> Now let's compare rv64-compat with rv32-native memory footprint with almost the same
> defconfig, rootfs, opensbi in one qemu.
>
>  - Run rv64 with rv32 rootfs in compat mode:
>    $ ./build/qemu-system-riscv64 -cpu rv64 -M virt -m 64m -nographic -bios qemu_riscv64_virt_defconfig/images/fw_jump.bin -kernel build-rv64/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0
>
> QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
> OpenSBI v0.9
> [    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv64-unknown-linux-gnu-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.37) #96 SMP Tue Dec 28 21:01:55 CST 2021
> [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
> [    0.000000] Machine model: riscv-virtio,qemu
> [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
> [    0.000000] printk: bootconsole [sbi0] enabled
> [    0.000000] efi: UEFI not found.
> [    0.000000] Zone ranges:
> [    0.000000]   DMA32    [mem 0x0000000080200000-0x0000000083ffffff]
> [    0.000000]   Normal   empty
> [    0.000000] Movable zone start for each node
> [    0.000000] Early memory node ranges
> [    0.000000]   node   0: [mem 0x0000000080200000-0x0000000083ffffff]
> [    0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x0000000083ffffff]
> [    0.000000] SBI specification v0.2 detected
> [    0.000000] SBI implementation ID=0x1 Version=0x9
> [    0.000000] SBI TIME extension detected
> [    0.000000] SBI IPI extension detected
> [    0.000000] SBI RFENCE extension detected
> [    0.000000] SBI v0.2 HSM extension detected
> [    0.000000] riscv: ISA extensions acdfhimsu
> [    0.000000] riscv: ELF capabilities acdfim
> [    0.000000] percpu: Embedded 17 pages/cpu s30696 r8192 d30744 u69632
> [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15655
> [    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
> [    0.000000] Dentry cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
> [    0.000000] Inode-cache hash table entries: 4096 (order: 3, 32768 bytes, linear)
> [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> [    0.000000] Virtual kernel memory layout:
> [    0.000000]       fixmap : 0xffffffcefee00000 - 0xffffffceff000000   (2048 kB)
> [    0.000000]       pci io : 0xffffffceff000000 - 0xffffffcf00000000   (  16 MB)
> [    0.000000]      vmemmap : 0xffffffcf00000000 - 0xffffffcfffffffff   (4095 MB)
> [    0.000000]      vmalloc : 0xffffffd000000000 - 0xffffffdfffffffff   (65535 MB)
> [    0.000000]       lowmem : 0xffffffe000000000 - 0xffffffe003e00000   (  62 MB)
> [    0.000000]       kernel : 0xffffffff80000000 - 0xffffffffffffffff   (2047 MB)
> [    0.000000] Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved, 0K cma-reserved)
> [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> [    0.000000] rcu: Hierarchical RCU implementation.
> [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
> [    0.000000] rcu:     RCU debug extended QS entry/exit.
> [    0.000000]  Tracing variant of Tasks RCU enabled.
> [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
> [    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
> [    0.000000] riscv-intc: 64 local interrupts mapped
> [    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
> ...
> Welcome to Buildroot
> buildroot login: root
> # cat /proc/cpuinfo
> processor       : 0
> hart            : 0
> isa             : rv64imafdcsuh
> mmu             : sv48
>
> # file /bin/busybox
> /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
> # ca[   78.386630] random: fast init done
> # cat /proc/meminfo
> MemTotal:          53076 kB
> MemFree:           40264 kB
> MemAvailable:      40244 kB
> Buffers:             236 kB
> Cached:             1560 kB
> SwapCached:            0 kB
> Active:             1700 kB
> Inactive:            516 kB
> Active(anon):         40 kB
> Inactive(anon):      424 kB
> Active(file):       1660 kB
> Inactive(file):       92 kB
> Unevictable:           0 kB
> Mlocked:               0 kB
> SwapTotal:             0 kB
> SwapFree:              0 kB
> Dirty:                 0 kB
> Writeback:             0 kB
> AnonPages:           444 kB
> Mapped:             1188 kB
> Shmem:                44 kB
> KReclaimable:        952 kB
> Slab:               5744 kB
> SReclaimable:        952 kB
> SUnreclaim:         4792 kB
> KernelStack:         624 kB
> PageTables:          156 kB
> NFS_Unstable:          0 kB
> Bounce:                0 kB
> WritebackTmp:          0 kB
> CommitLimit:       26536 kB
> Committed_AS:       1748 kB
> VmallocTotal:   67108863 kB
> VmallocUsed:         652 kB
> VmallocChunk:          0 kB
> Percpu:               80 kB
> #
>
>  - Run rv32 with rv32 rootfs:
>    $ ./build/qemu-system-riscv32 -cpu rv32 -M virt -m 64m -nographic -bios qemu_riscv32_virt_defconfig/images/fw_jump.bin -kernel build-rv32/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0
>
> QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
> OpenSBI v0.9
> [    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv32-buildroot-linux-gnu-gcc.br_real (Buildroot 2021.11-201-g7600ca7960-dirty) 10.3.0, GNU ld (GNU Binutils) 2.36.1) #7 SMP Tue Dec 28 21:02:21 CST 2021
> [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80400000
> [    0.000000] Machine model: riscv-virtio,qemu
> [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
> [    0.000000] printk: bootconsole [sbi0] enabled
> [    0.000000] efi: UEFI not found.
> [    0.000000] Zone ranges:
> [    0.000000]   Normal   [mem 0x0000000080400000-0x0000000083ffffff]
> [    0.000000] Movable zone start for each node
> [    0.000000] Early memory node ranges
> [    0.000000]   node   0: [mem 0x0000000080400000-0x0000000083ffffff]
> [    0.000000] Initmem setup node 0 [mem 0x0000000080400000-0x0000000083ffffff]
> [    0.000000] SBI specification v0.2 detected
> [    0.000000] SBI implementation ID=0x1 Version=0x9
> [    0.000000] SBI TIME extension detected
> [    0.000000] SBI IPI extension detected
> [    0.000000] SBI RFENCE extension detected
> [    0.000000] SBI v0.2 HSM extension detected
> [    0.000000] riscv: ISA extensions acdfhimsu
> [    0.000000] riscv: ELF capabilities acdfim
> [    0.000000] percpu: Embedded 12 pages/cpu s16600 r8192 d24360 u49152
> [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15240
> [    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
> [    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, linear)
> [    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, linear)
> [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> [    0.000000] Virtual kernel memory layout:
> [    0.000000]       fixmap : 0x9dc00000 - 0x9e000000   (4096 kB)
> [    0.000000]       pci io : 0x9e000000 - 0x9f000000   (  16 MB)
> [    0.000000]      vmemmap : 0x9f000000 - 0x9fffffff   (  15 MB)
> [    0.000000]      vmalloc : 0xa0000000 - 0xbfffffff   ( 511 MB)
> [    0.000000]       lowmem : 0xc0000000 - 0xc3c00000   (  60 MB)
> [    0.000000] Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss, 9516K reserved, 0K cma-reserved)
> [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> [    0.000000] rcu: Hierarchical RCU implementation.
> [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
> [    0.000000] rcu:     RCU debug extended QS entry/exit.
> [    0.000000]  Tracing variant of Tasks RCU enabled.
> [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
> [    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
> [    0.000000] riscv-intc: 32 local interrupts mapped
> [    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
> ...
> Welcome to Buildroot
> buildroot login: root
> # cat /proc/cpuinfo
> processor       : 0
> hart            : 0
> isa             : rv32imafdcsuh
> mmu             : sv32
>
> # file /bin/busybox
> /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
> [   79.320589] random: fast init done
> # cat /proc/meminfo
> MemTotal:          52176 kB
> MemFree:           41012 kB
> MemAvailable:      42176 kB
> Buffers:             644 kB
> Cached:             2724 kB
> SwapCached:            0 kB
> Active:             3128 kB
> Inactive:            752 kB
> Active(anon):         40 kB
> Inactive(anon):      516 kB
> Active(file):       3088 kB
> Inactive(file):      236 kB
> Unevictable:           0 kB
> Mlocked:               0 kB
> SwapTotal:             0 kB
> SwapFree:              0 kB
> Dirty:                 4 kB
> Writeback:             0 kB
> AnonPages:           556 kB
> Mapped:             2172 kB
> Shmem:                44 kB
> KReclaimable:        656 kB
> Slab:               3684 kB
> SReclaimable:        656 kB
> SUnreclaim:         3028 kB
> KernelStack:         312 kB
> PageTables:           88 kB
> NFS_Unstable:          0 kB
> Bounce:                0 kB
> WritebackTmp:          0 kB
> CommitLimit:       26088 kB
> Committed_AS:       2088 kB
> VmallocTotal:     524287 kB
> VmallocUsed:          12 kB
> VmallocChunk:          0 kB
> Percpu:               60 kB
> #
>
>  Some conclusions:
>  - kernel statics:
>    64: Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved)
>    32: Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss,  9516K reserved)
>    rv32 better than rv64:                  1%               22%           17%          13%        19%         11%
>    The code size is very similar, but data size rv32 would be better.
>
>  - rv32 kernel runtime KernelStack, Slab... are smaller,
>    rv64: MemTotal: 53076 kB,        MemFree: 40264 kB
>    rv32: MemTotal: 52176 + 2048 kB, MemFree: 41012  + 2048 kB
>    rv32 better than rv64:       2%                         6%
>
>    (Because opensbi problem, we could add another 2MB for rv32.)
>    Overall in 64MB memory situation, rv64-compat is 6% worse than rv32-native
>    at memory footprint. If the userspace memory usage increases, I think
>    the gap will be further reduced.
>
> Changes in v9:
>  - Fixup rv32 call rv64 segment fault
>  - Ready for 5.18

Thanks.  I'd also seen some arm64 autobuilder failures, not sure if 
those got fixed as I don't see anything specificlly listed in here 
(sorry if I just missed it).

I've gone ahead and put this on palmer/riscv-compat, I'm going to let it 
sit at least overnight before putting it on for-next proper.  It's a 
big one and the autobuilders seem to find stuff over there, I don't want 
to break any of the other ports.  IIRC you were getting CC'd on the 
build failures I was seeing.

If it's clean I'll merge it into for-next propely.  It's passing my 
staging merge tests, but I don't yet have anything specifically for 
compat -- at least it's not causing any regressions, though.

>
> Changes in v8:
>  - Enhanced elf_check_arch with EI_CLASS
>  - Fixup SR_UXL doesn't exist in CONFIG_32BIT
>  - Add Tested-by with Heiko
>  - Update qemu compile tips with upstream repo
>
> Changes in v7:
>  - Re-construct compat_vdso/Makefile
>  - Fixup disable COMPAT compile error by csr.h's macro.
>  - Optimize coding convention for lo/hi in compat.h
>
> Changes in v6:
>  - Rebase on linux-5.17-rc5
>  - Optimize hw capability check for elf
>  - Optimize comment in thread_info.h
>  - Optimize start_thread with SR_UXL setting
>  - Optimize vdso.c with direct panic
>
> Changes in v5:
>  - Rebase on linux-5.17-rc2
>  - Include consolidate the fcntl patches by Christoph Hellwig
>  - Remove F_GETLK64/F_SETLK64/F_SETLKW64 from asm/compat.h
>  - Change COMPAT_RLIM_INFINITY from 0x7fffffff to 0xffffffff
>  - Bring back "Add hw-cap detect in setup_arch patch" in v1
>
> Changes in v4:
>  - Rebase on linux-5.17-rc1
>  - Optimize compat_sys_call_table implementation with Arnd's advice
>  - Add reviewed-by for Arnd. Thx :)
>  - Remove FIXME comment in elf.h
>  - Optimize Cleanup duplicate definitions in compat.h with Arnd's advice
>
> Changes in v3:
>  - Rebase on newest master (pre linux-5.17-rc1)
>  - Using newest qemu version v7 for test
>  - Remove fcntl common modification
>  - Fixup SET_PERSONALITY in elf.h by Arnd
>  - Fixup KVM Kconfig
>  - Update Acked-by & Reviewed-by
>
> Changes in v2:
>  - Add __ARCH_WANT_COMPAT_STAT suggested
>  - Cleanup fcntl compatduplicate definitions
>  - Cleanup compat.h
>  - Move rv32_defconfig into Makefile
>  - Fixup rv64 rootfs boot failed, remove hw_compat_mode_detect
>  - Move SYSVIPC_COMPAT into init/Kconfig
>  - Simplify compat_elf_check
>
> Christoph Hellwig (3):
>   uapi: simplify __ARCH_FLOCK{,64}_PAD a little
>   uapi: always define F_GETLK64/F_SETLK64/F_SETLKW64 in fcntl.h
>   compat: consolidate the compat_flock{,64} definition
>
> Guo Ren (17):
>   kconfig: Add SYSVIPC_COMPAT for all architectures
>   fs: stat: compat: Add __ARCH_WANT_COMPAT_STAT
>   asm-generic: compat: Cleanup duplicate definitions
>   syscalls: compat: Fix the missing part for __SYSCALL_COMPAT
>   riscv: Fixup difference with defconfig
>   riscv: compat: Add basic compat data type implementation
>   riscv: compat: Re-implement TASK_SIZE for COMPAT_32BIT
>   riscv: compat: syscall: Add compat_sys_call_table implementation
>   riscv: compat: syscall: Add entry.S implementation
>   riscv: compat: process: Add UXL_32 support in start_thread
>   riscv: compat: Add elf.h implementation
>   riscv: compat: Add hw capability check for elf
>   riscv: compat: vdso: Add COMPAT_VDSO base code implementation
>   riscv: compat: vdso: Add setup additional pages implementation
>   riscv: compat: signal: Add rt_frame implementation
>   riscv: compat: ptrace: Add compat_arch_ptrace implement
>   riscv: compat: Add COMPAT Kbuild skeletal support
>
>  arch/arm64/Kconfig                            |   4 -
>  arch/arm64/include/asm/compat.h               |  91 +------
>  arch/arm64/include/asm/unistd.h               |   1 +
>  arch/mips/Kconfig                             |   5 -
>  arch/mips/include/asm/compat.h                |  41 +--
>  arch/mips/include/asm/unistd.h                |   2 +
>  arch/mips/include/uapi/asm/fcntl.h            |  30 +--
>  arch/parisc/Kconfig                           |   4 -
>  arch/parisc/include/asm/compat.h              |  45 +---
>  arch/parisc/include/asm/unistd.h              |   1 +
>  arch/powerpc/Kconfig                          |   5 -
>  arch/powerpc/include/asm/compat.h             |  50 +---
>  arch/powerpc/include/asm/unistd.h             |   1 +
>  arch/riscv/Kconfig                            |  19 ++
>  arch/riscv/Makefile                           |   9 +
>  arch/riscv/configs/rv32_defconfig             | 135 ----------
>  arch/riscv/include/asm/compat.h               | 129 ++++++++++
>  arch/riscv/include/asm/csr.h                  |   7 +
>  arch/riscv/include/asm/elf.h                  |  50 +++-
>  arch/riscv/include/asm/mmu.h                  |   1 +
>  arch/riscv/include/asm/pgtable.h              |  13 +-
>  arch/riscv/include/asm/processor.h            |   6 +-
>  arch/riscv/include/asm/syscall.h              |   1 +
>  arch/riscv/include/asm/thread_info.h          |   1 +
>  arch/riscv/include/asm/unistd.h               |  11 +
>  arch/riscv/include/asm/vdso.h                 |   9 +
>  arch/riscv/include/uapi/asm/unistd.h          |   2 +-
>  arch/riscv/kernel/Makefile                    |   3 +
>  arch/riscv/kernel/compat_signal.c             | 243 ++++++++++++++++++
>  arch/riscv/kernel/compat_syscall_table.c      |  19 ++
>  arch/riscv/kernel/compat_vdso/.gitignore      |   2 +
>  arch/riscv/kernel/compat_vdso/Makefile        |  78 ++++++
>  arch/riscv/kernel/compat_vdso/compat_vdso.S   |   8 +
>  .../kernel/compat_vdso/compat_vdso.lds.S      |   3 +
>  arch/riscv/kernel/compat_vdso/flush_icache.S  |   3 +
>  .../compat_vdso/gen_compat_vdso_offsets.sh    |   5 +
>  arch/riscv/kernel/compat_vdso/getcpu.S        |   3 +
>  arch/riscv/kernel/compat_vdso/note.S          |   3 +
>  arch/riscv/kernel/compat_vdso/rt_sigreturn.S  |   3 +
>  arch/riscv/kernel/entry.S                     |  18 +-
>  arch/riscv/kernel/process.c                   |  37 +++
>  arch/riscv/kernel/ptrace.c                    |  87 ++++++-
>  arch/riscv/kernel/signal.c                    |  13 +-
>  arch/riscv/kernel/sys_riscv.c                 |   6 +-
>  arch/riscv/kernel/vdso.c                      | 105 +++++---
>  arch/riscv/kernel/vdso/vdso.S                 |   6 +-
>  arch/s390/Kconfig                             |   3 -
>  arch/s390/include/asm/compat.h                |  99 +------
>  arch/s390/include/asm/unistd.h                |   1 +
>  arch/sparc/Kconfig                            |   5 -
>  arch/sparc/include/asm/compat.h               |  61 ++---
>  arch/sparc/include/asm/unistd.h               |   1 +
>  arch/x86/Kconfig                              |   4 -
>  arch/x86/include/asm/compat.h                 | 104 ++------
>  arch/x86/include/asm/unistd.h                 |   1 +
>  fs/open.c                                     |  24 ++
>  fs/read_write.c                               |  16 ++
>  fs/stat.c                                     |   2 +-
>  fs/sync.c                                     |   9 +
>  include/asm-generic/compat.h                  | 113 ++++++++
>  include/linux/compat.h                        |  68 +++++
>  include/uapi/asm-generic/fcntl.h              |  23 +-
>  include/uapi/asm-generic/unistd.h             |   4 +-
>  init/Kconfig                                  |   4 +
>  mm/fadvise.c                                  |  11 +
>  mm/readahead.c                                |   7 +
>  tools/include/uapi/asm-generic/fcntl.h        |  21 +-
>  tools/include/uapi/asm-generic/unistd.h       |   4 +-
>  68 files changed, 1205 insertions(+), 698 deletions(-)
>  delete mode 100644 arch/riscv/configs/rv32_defconfig
>  create mode 100644 arch/riscv/include/asm/compat.h
>  create mode 100644 arch/riscv/kernel/compat_signal.c
>  create mode 100644 arch/riscv/kernel/compat_syscall_table.c
>  create mode 100644 arch/riscv/kernel/compat_vdso/.gitignore
>  create mode 100644 arch/riscv/kernel/compat_vdso/Makefile
>  create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.S
>  create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.lds.S
>  create mode 100644 arch/riscv/kernel/compat_vdso/flush_icache.S
>  create mode 100755 arch/riscv/kernel/compat_vdso/gen_compat_vdso_offsets.sh
>  create mode 100644 arch/riscv/kernel/compat_vdso/getcpu.S
>  create mode 100644 arch/riscv/kernel/compat_vdso/note.S
>  create mode 100644 arch/riscv/kernel/compat_vdso/rt_sigreturn.S

Re: [PATCH V9 00/20] riscv: compat: Add COMPAT Kbuild skeletal support

Posted by Guo Ren 4 years, 2 months ago

On Wed, Mar 23, 2022 at 5:00 AM Palmer Dabbelt <palmer@dabbelt.com> wrote:
>
> On Tue, 22 Mar 2022 07:39:43 PDT (-0700), guoren@kernel.org wrote:
> > From: Guo Ren <guoren@linux.alibaba.com>
> >
> > Currently, most 64-bit architectures (x86, parisc, powerpc, arm64,
> > s390, mips, sparc) have supported COMPAT mode. But they all have
> > history issues and can't use standard linux unistd.h. RISC-V would
> > be first standard __SYSCALL_COMPAT user of include/uapi/asm-generic
> > /unistd.h.
> >
> > The patchset are based on v5.17-rc8, you can compare rv64-compat
> > v.s. rv32-native in qemu with following steps:
> >
> >  - Prepare rv32 rootfs & fw_jump.bin by buildroot.org
> >    $ git clone git://git.busybox.net/buildroot
> >    $ cd buildroot
> >    $ make qemu_riscv32_virt_defconfig O=qemu_riscv32_virt_defconfig
> >    $ make -C qemu_riscv32_virt_defconfig
> >    $ make qemu_riscv64_virt_defconfig O=qemu_riscv64_virt_defconfig
> >    $ make -C qemu_riscv64_virt_defconfig
> >    (Got fw_jump.bin & rootfs.ext2 in qemu_riscvXX_virt_defconfig/images)
> >
> >  - Prepare Linux rv32 & rv64 Image
> >    $ git clone git@github.com:c-sky/csky-linux.git -b riscv_compat_v8 linux
> >    $ cd linux
> >    $ echo "CONFIG_STRICT_KERNEL_RWX=n" >> arch/riscv/configs/defconfig
> >    $ echo "CONFIG_STRICT_MODULE_RWX=n" >> arch/riscv/configs/defconfig
> >    $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ rv32_defconfig
> >    $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ Image
> >    $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ defconfig
> >    $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ Image
> >
> >  - Prepare Qemu:
> >    $ git clone https://gitlab.com/qemu-project/qemu.git -b master linux
> >    $ cd qemu
> >    $ ./configure --target-list="riscv64-softmmu riscv32-softmmu"
> >    $ make
> >
> > Now let's compare rv64-compat with rv32-native memory footprint with almost the same
> > defconfig, rootfs, opensbi in one qemu.
> >
> >  - Run rv64 with rv32 rootfs in compat mode:
> >    $ ./build/qemu-system-riscv64 -cpu rv64 -M virt -m 64m -nographic -bios qemu_riscv64_virt_defconfig/images/fw_jump.bin -kernel build-rv64/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0
> >
> > QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
> > OpenSBI v0.9
> > [    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv64-unknown-linux-gnu-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.37) #96 SMP Tue Dec 28 21:01:55 CST 2021
> > [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
> > [    0.000000] Machine model: riscv-virtio,qemu
> > [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
> > [    0.000000] printk: bootconsole [sbi0] enabled
> > [    0.000000] efi: UEFI not found.
> > [    0.000000] Zone ranges:
> > [    0.000000]   DMA32    [mem 0x0000000080200000-0x0000000083ffffff]
> > [    0.000000]   Normal   empty
> > [    0.000000] Movable zone start for each node
> > [    0.000000] Early memory node ranges
> > [    0.000000]   node   0: [mem 0x0000000080200000-0x0000000083ffffff]
> > [    0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x0000000083ffffff]
> > [    0.000000] SBI specification v0.2 detected
> > [    0.000000] SBI implementation ID=0x1 Version=0x9
> > [    0.000000] SBI TIME extension detected
> > [    0.000000] SBI IPI extension detected
> > [    0.000000] SBI RFENCE extension detected
> > [    0.000000] SBI v0.2 HSM extension detected
> > [    0.000000] riscv: ISA extensions acdfhimsu
> > [    0.000000] riscv: ELF capabilities acdfim
> > [    0.000000] percpu: Embedded 17 pages/cpu s30696 r8192 d30744 u69632
> > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15655
> > [    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
> > [    0.000000] Dentry cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
> > [    0.000000] Inode-cache hash table entries: 4096 (order: 3, 32768 bytes, linear)
> > [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> > [    0.000000] Virtual kernel memory layout:
> > [    0.000000]       fixmap : 0xffffffcefee00000 - 0xffffffceff000000   (2048 kB)
> > [    0.000000]       pci io : 0xffffffceff000000 - 0xffffffcf00000000   (  16 MB)
> > [    0.000000]      vmemmap : 0xffffffcf00000000 - 0xffffffcfffffffff   (4095 MB)
> > [    0.000000]      vmalloc : 0xffffffd000000000 - 0xffffffdfffffffff   (65535 MB)
> > [    0.000000]       lowmem : 0xffffffe000000000 - 0xffffffe003e00000   (  62 MB)
> > [    0.000000]       kernel : 0xffffffff80000000 - 0xffffffffffffffff   (2047 MB)
> > [    0.000000] Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved, 0K cma-reserved)
> > [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> > [    0.000000] rcu: Hierarchical RCU implementation.
> > [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
> > [    0.000000] rcu:     RCU debug extended QS entry/exit.
> > [    0.000000]  Tracing variant of Tasks RCU enabled.
> > [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> > [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
> > [    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
> > [    0.000000] riscv-intc: 64 local interrupts mapped
> > [    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
> > ...
> > Welcome to Buildroot
> > buildroot login: root
> > # cat /proc/cpuinfo
> > processor       : 0
> > hart            : 0
> > isa             : rv64imafdcsuh
> > mmu             : sv48
> >
> > # file /bin/busybox
> > /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
> > # ca[   78.386630] random: fast init done
> > # cat /proc/meminfo
> > MemTotal:          53076 kB
> > MemFree:           40264 kB
> > MemAvailable:      40244 kB
> > Buffers:             236 kB
> > Cached:             1560 kB
> > SwapCached:            0 kB
> > Active:             1700 kB
> > Inactive:            516 kB
> > Active(anon):         40 kB
> > Inactive(anon):      424 kB
> > Active(file):       1660 kB
> > Inactive(file):       92 kB
> > Unevictable:           0 kB
> > Mlocked:               0 kB
> > SwapTotal:             0 kB
> > SwapFree:              0 kB
> > Dirty:                 0 kB
> > Writeback:             0 kB
> > AnonPages:           444 kB
> > Mapped:             1188 kB
> > Shmem:                44 kB
> > KReclaimable:        952 kB
> > Slab:               5744 kB
> > SReclaimable:        952 kB
> > SUnreclaim:         4792 kB
> > KernelStack:         624 kB
> > PageTables:          156 kB
> > NFS_Unstable:          0 kB
> > Bounce:                0 kB
> > WritebackTmp:          0 kB
> > CommitLimit:       26536 kB
> > Committed_AS:       1748 kB
> > VmallocTotal:   67108863 kB
> > VmallocUsed:         652 kB
> > VmallocChunk:          0 kB
> > Percpu:               80 kB
> > #
> >
> >  - Run rv32 with rv32 rootfs:
> >    $ ./build/qemu-system-riscv32 -cpu rv32 -M virt -m 64m -nographic -bios qemu_riscv32_virt_defconfig/images/fw_jump.bin -kernel build-rv32/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0
> >
> > QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
> > OpenSBI v0.9
> > [    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv32-buildroot-linux-gnu-gcc.br_real (Buildroot 2021.11-201-g7600ca7960-dirty) 10.3.0, GNU ld (GNU Binutils) 2.36.1) #7 SMP Tue Dec 28 21:02:21 CST 2021
> > [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80400000
> > [    0.000000] Machine model: riscv-virtio,qemu
> > [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
> > [    0.000000] printk: bootconsole [sbi0] enabled
> > [    0.000000] efi: UEFI not found.
> > [    0.000000] Zone ranges:
> > [    0.000000]   Normal   [mem 0x0000000080400000-0x0000000083ffffff]
> > [    0.000000] Movable zone start for each node
> > [    0.000000] Early memory node ranges
> > [    0.000000]   node   0: [mem 0x0000000080400000-0x0000000083ffffff]
> > [    0.000000] Initmem setup node 0 [mem 0x0000000080400000-0x0000000083ffffff]
> > [    0.000000] SBI specification v0.2 detected
> > [    0.000000] SBI implementation ID=0x1 Version=0x9
> > [    0.000000] SBI TIME extension detected
> > [    0.000000] SBI IPI extension detected
> > [    0.000000] SBI RFENCE extension detected
> > [    0.000000] SBI v0.2 HSM extension detected
> > [    0.000000] riscv: ISA extensions acdfhimsu
> > [    0.000000] riscv: ELF capabilities acdfim
> > [    0.000000] percpu: Embedded 12 pages/cpu s16600 r8192 d24360 u49152
> > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15240
> > [    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
> > [    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, linear)
> > [    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, linear)
> > [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> > [    0.000000] Virtual kernel memory layout:
> > [    0.000000]       fixmap : 0x9dc00000 - 0x9e000000   (4096 kB)
> > [    0.000000]       pci io : 0x9e000000 - 0x9f000000   (  16 MB)
> > [    0.000000]      vmemmap : 0x9f000000 - 0x9fffffff   (  15 MB)
> > [    0.000000]      vmalloc : 0xa0000000 - 0xbfffffff   ( 511 MB)
> > [    0.000000]       lowmem : 0xc0000000 - 0xc3c00000   (  60 MB)
> > [    0.000000] Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss, 9516K reserved, 0K cma-reserved)
> > [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> > [    0.000000] rcu: Hierarchical RCU implementation.
> > [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
> > [    0.000000] rcu:     RCU debug extended QS entry/exit.
> > [    0.000000]  Tracing variant of Tasks RCU enabled.
> > [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> > [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
> > [    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
> > [    0.000000] riscv-intc: 32 local interrupts mapped
> > [    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
> > ...
> > Welcome to Buildroot
> > buildroot login: root
> > # cat /proc/cpuinfo
> > processor       : 0
> > hart            : 0
> > isa             : rv32imafdcsuh
> > mmu             : sv32
> >
> > # file /bin/busybox
> > /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
> > [   79.320589] random: fast init done
> > # cat /proc/meminfo
> > MemTotal:          52176 kB
> > MemFree:           41012 kB
> > MemAvailable:      42176 kB
> > Buffers:             644 kB
> > Cached:             2724 kB
> > SwapCached:            0 kB
> > Active:             3128 kB
> > Inactive:            752 kB
> > Active(anon):         40 kB
> > Inactive(anon):      516 kB
> > Active(file):       3088 kB
> > Inactive(file):      236 kB
> > Unevictable:           0 kB
> > Mlocked:               0 kB
> > SwapTotal:             0 kB
> > SwapFree:              0 kB
> > Dirty:                 4 kB
> > Writeback:             0 kB
> > AnonPages:           556 kB
> > Mapped:             2172 kB
> > Shmem:                44 kB
> > KReclaimable:        656 kB
> > Slab:               3684 kB
> > SReclaimable:        656 kB
> > SUnreclaim:         3028 kB
> > KernelStack:         312 kB
> > PageTables:           88 kB
> > NFS_Unstable:          0 kB
> > Bounce:                0 kB
> > WritebackTmp:          0 kB
> > CommitLimit:       26088 kB
> > Committed_AS:       2088 kB
> > VmallocTotal:     524287 kB
> > VmallocUsed:          12 kB
> > VmallocChunk:          0 kB
> > Percpu:               60 kB
> > #
> >
> >  Some conclusions:
> >  - kernel statics:
> >    64: Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved)
> >    32: Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss,  9516K reserved)
> >    rv32 better than rv64:                  1%               22%           17%          13%        19%         11%
> >    The code size is very similar, but data size rv32 would be better.
> >
> >  - rv32 kernel runtime KernelStack, Slab... are smaller,
> >    rv64: MemTotal: 53076 kB,        MemFree: 40264 kB
> >    rv32: MemTotal: 52176 + 2048 kB, MemFree: 41012  + 2048 kB
> >    rv32 better than rv64:       2%                         6%
> >
> >    (Because opensbi problem, we could add another 2MB for rv32.)
> >    Overall in 64MB memory situation, rv64-compat is 6% worse than rv32-native
> >    at memory footprint. If the userspace memory usage increases, I think
> >    the gap will be further reduced.
> >
> > Changes in v9:
> >  - Fixup rv32 call rv64 segment fault
> >  - Ready for 5.18
>
> Thanks.  I'd also seen some arm64 autobuilder failures, not sure if
> those got fixed as I don't see anything specificlly listed in here
> (sorry if I just missed it).
>
> I've gone ahead and put this on palmer/riscv-compat, I'm going to let it
> sit at least overnight before putting it on for-next proper.  It's a
> big one and the autobuilders seem to find stuff over there, I don't want
> to break any of the other ports.  IIRC you were getting CC'd on the
> build failures I was seeing.
I couldn't find that, could you give me a link, thank you.

>
> If it's clean I'll merge it into for-next propely.  It's passing my
> staging merge tests, but I don't yet have anything specifically for
> compat -- at least it's not causing any regressions, though.
>
> >
> > Changes in v8:
> >  - Enhanced elf_check_arch with EI_CLASS
> >  - Fixup SR_UXL doesn't exist in CONFIG_32BIT
> >  - Add Tested-by with Heiko
> >  - Update qemu compile tips with upstream repo
> >
> > Changes in v7:
> >  - Re-construct compat_vdso/Makefile
> >  - Fixup disable COMPAT compile error by csr.h's macro.
> >  - Optimize coding convention for lo/hi in compat.h
> >
> > Changes in v6:
> >  - Rebase on linux-5.17-rc5
> >  - Optimize hw capability check for elf
> >  - Optimize comment in thread_info.h
> >  - Optimize start_thread with SR_UXL setting
> >  - Optimize vdso.c with direct panic
> >
> > Changes in v5:
> >  - Rebase on linux-5.17-rc2
> >  - Include consolidate the fcntl patches by Christoph Hellwig
> >  - Remove F_GETLK64/F_SETLK64/F_SETLKW64 from asm/compat.h
> >  - Change COMPAT_RLIM_INFINITY from 0x7fffffff to 0xffffffff
> >  - Bring back "Add hw-cap detect in setup_arch patch" in v1
> >
> > Changes in v4:
> >  - Rebase on linux-5.17-rc1
> >  - Optimize compat_sys_call_table implementation with Arnd's advice
> >  - Add reviewed-by for Arnd. Thx :)
> >  - Remove FIXME comment in elf.h
> >  - Optimize Cleanup duplicate definitions in compat.h with Arnd's advice
> >
> > Changes in v3:
> >  - Rebase on newest master (pre linux-5.17-rc1)
> >  - Using newest qemu version v7 for test
> >  - Remove fcntl common modification
> >  - Fixup SET_PERSONALITY in elf.h by Arnd
> >  - Fixup KVM Kconfig
> >  - Update Acked-by & Reviewed-by
> >
> > Changes in v2:
> >  - Add __ARCH_WANT_COMPAT_STAT suggested
> >  - Cleanup fcntl compatduplicate definitions
> >  - Cleanup compat.h
> >  - Move rv32_defconfig into Makefile
> >  - Fixup rv64 rootfs boot failed, remove hw_compat_mode_detect
> >  - Move SYSVIPC_COMPAT into init/Kconfig
> >  - Simplify compat_elf_check
> >
> > Christoph Hellwig (3):
> >   uapi: simplify __ARCH_FLOCK{,64}_PAD a little
> >   uapi: always define F_GETLK64/F_SETLK64/F_SETLKW64 in fcntl.h
> >   compat: consolidate the compat_flock{,64} definition
> >
> > Guo Ren (17):
> >   kconfig: Add SYSVIPC_COMPAT for all architectures
> >   fs: stat: compat: Add __ARCH_WANT_COMPAT_STAT
> >   asm-generic: compat: Cleanup duplicate definitions
> >   syscalls: compat: Fix the missing part for __SYSCALL_COMPAT
> >   riscv: Fixup difference with defconfig
> >   riscv: compat: Add basic compat data type implementation
> >   riscv: compat: Re-implement TASK_SIZE for COMPAT_32BIT
> >   riscv: compat: syscall: Add compat_sys_call_table implementation
> >   riscv: compat: syscall: Add entry.S implementation
> >   riscv: compat: process: Add UXL_32 support in start_thread
> >   riscv: compat: Add elf.h implementation
> >   riscv: compat: Add hw capability check for elf
> >   riscv: compat: vdso: Add COMPAT_VDSO base code implementation
> >   riscv: compat: vdso: Add setup additional pages implementation
> >   riscv: compat: signal: Add rt_frame implementation
> >   riscv: compat: ptrace: Add compat_arch_ptrace implement
> >   riscv: compat: Add COMPAT Kbuild skeletal support
> >
> >  arch/arm64/Kconfig                            |   4 -
> >  arch/arm64/include/asm/compat.h               |  91 +------
> >  arch/arm64/include/asm/unistd.h               |   1 +
> >  arch/mips/Kconfig                             |   5 -
> >  arch/mips/include/asm/compat.h                |  41 +--
> >  arch/mips/include/asm/unistd.h                |   2 +
> >  arch/mips/include/uapi/asm/fcntl.h            |  30 +--
> >  arch/parisc/Kconfig                           |   4 -
> >  arch/parisc/include/asm/compat.h              |  45 +---
> >  arch/parisc/include/asm/unistd.h              |   1 +
> >  arch/powerpc/Kconfig                          |   5 -
> >  arch/powerpc/include/asm/compat.h             |  50 +---
> >  arch/powerpc/include/asm/unistd.h             |   1 +
> >  arch/riscv/Kconfig                            |  19 ++
> >  arch/riscv/Makefile                           |   9 +
> >  arch/riscv/configs/rv32_defconfig             | 135 ----------
> >  arch/riscv/include/asm/compat.h               | 129 ++++++++++
> >  arch/riscv/include/asm/csr.h                  |   7 +
> >  arch/riscv/include/asm/elf.h                  |  50 +++-
> >  arch/riscv/include/asm/mmu.h                  |   1 +
> >  arch/riscv/include/asm/pgtable.h              |  13 +-
> >  arch/riscv/include/asm/processor.h            |   6 +-
> >  arch/riscv/include/asm/syscall.h              |   1 +
> >  arch/riscv/include/asm/thread_info.h          |   1 +
> >  arch/riscv/include/asm/unistd.h               |  11 +
> >  arch/riscv/include/asm/vdso.h                 |   9 +
> >  arch/riscv/include/uapi/asm/unistd.h          |   2 +-
> >  arch/riscv/kernel/Makefile                    |   3 +
> >  arch/riscv/kernel/compat_signal.c             | 243 ++++++++++++++++++
> >  arch/riscv/kernel/compat_syscall_table.c      |  19 ++
> >  arch/riscv/kernel/compat_vdso/.gitignore      |   2 +
> >  arch/riscv/kernel/compat_vdso/Makefile        |  78 ++++++
> >  arch/riscv/kernel/compat_vdso/compat_vdso.S   |   8 +
> >  .../kernel/compat_vdso/compat_vdso.lds.S      |   3 +
> >  arch/riscv/kernel/compat_vdso/flush_icache.S  |   3 +
> >  .../compat_vdso/gen_compat_vdso_offsets.sh    |   5 +
> >  arch/riscv/kernel/compat_vdso/getcpu.S        |   3 +
> >  arch/riscv/kernel/compat_vdso/note.S          |   3 +
> >  arch/riscv/kernel/compat_vdso/rt_sigreturn.S  |   3 +
> >  arch/riscv/kernel/entry.S                     |  18 +-
> >  arch/riscv/kernel/process.c                   |  37 +++
> >  arch/riscv/kernel/ptrace.c                    |  87 ++++++-
> >  arch/riscv/kernel/signal.c                    |  13 +-
> >  arch/riscv/kernel/sys_riscv.c                 |   6 +-
> >  arch/riscv/kernel/vdso.c                      | 105 +++++---
> >  arch/riscv/kernel/vdso/vdso.S                 |   6 +-
> >  arch/s390/Kconfig                             |   3 -
> >  arch/s390/include/asm/compat.h                |  99 +------
> >  arch/s390/include/asm/unistd.h                |   1 +
> >  arch/sparc/Kconfig                            |   5 -
> >  arch/sparc/include/asm/compat.h               |  61 ++---
> >  arch/sparc/include/asm/unistd.h               |   1 +
> >  arch/x86/Kconfig                              |   4 -
> >  arch/x86/include/asm/compat.h                 | 104 ++------
> >  arch/x86/include/asm/unistd.h                 |   1 +
> >  fs/open.c                                     |  24 ++
> >  fs/read_write.c                               |  16 ++
> >  fs/stat.c                                     |   2 +-
> >  fs/sync.c                                     |   9 +
> >  include/asm-generic/compat.h                  | 113 ++++++++
> >  include/linux/compat.h                        |  68 +++++
> >  include/uapi/asm-generic/fcntl.h              |  23 +-
> >  include/uapi/asm-generic/unistd.h             |   4 +-
> >  init/Kconfig                                  |   4 +
> >  mm/fadvise.c                                  |  11 +
> >  mm/readahead.c                                |   7 +
> >  tools/include/uapi/asm-generic/fcntl.h        |  21 +-
> >  tools/include/uapi/asm-generic/unistd.h       |   4 +-
> >  68 files changed, 1205 insertions(+), 698 deletions(-)
> >  delete mode 100644 arch/riscv/configs/rv32_defconfig
> >  create mode 100644 arch/riscv/include/asm/compat.h
> >  create mode 100644 arch/riscv/kernel/compat_signal.c
> >  create mode 100644 arch/riscv/kernel/compat_syscall_table.c
> >  create mode 100644 arch/riscv/kernel/compat_vdso/.gitignore
> >  create mode 100644 arch/riscv/kernel/compat_vdso/Makefile
> >  create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.S
> >  create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.lds.S
> >  create mode 100644 arch/riscv/kernel/compat_vdso/flush_icache.S
> >  create mode 100755 arch/riscv/kernel/compat_vdso/gen_compat_vdso_offsets.sh
> >  create mode 100644 arch/riscv/kernel/compat_vdso/getcpu.S
> >  create mode 100644 arch/riscv/kernel/compat_vdso/note.S
> >  create mode 100644 arch/riscv/kernel/compat_vdso/rt_sigreturn.S



--
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/

Re: [PATCH V9 00/20] riscv: compat: Add COMPAT Kbuild skeletal support

Posted by Guo Ren 4 years, 2 months ago

I got that. I fixed up it in v10.

CC      arch/arm64/kernel/asm-offsets.s
In file included from
/home/guoren/source/kernel/riscv-linux/arch/arm64/include/asm/stat.h:13,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/stat.h:6,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/sysfs.h:22,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/kobject.h:20,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/of.h:17,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/irqdomain.h:35,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/acpi.h:13,
                 from
/home/guoren/source/kernel/riscv-linux/include/acpi/apei.h:9,
                 from
/home/guoren/source/kernel/riscv-linux/include/acpi/ghes.h:5,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/arm_sdei.h:8,
                 from
/home/guoren/source/kernel/riscv-linux/arch/arm64/kernel/asm-offsets.c:10:
/home/guoren/source/kernel/riscv-linux/arch/arm64/include/asm/compat.h:69:8:
error: redefinition of ‘struct compat_statfs’
   69 | struct compat_statfs {
      |        ^~~~~~~~~~~~~
In file included from
/home/guoren/source/kernel/riscv-linux/arch/arm64/include/asm/compat.h:18,
                 from
/home/guoren/source/kernel/riscv-linux/arch/arm64/include/asm/stat.h:13,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/stat.h:6,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/sysfs.h:22,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/kobject.h:20,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/of.h:17,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/irqdomain.h:35,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/acpi.h:13,
                 from
/home/guoren/source/kernel/riscv-linux/include/acpi/apei.h:9,
                 from
/home/guoren/source/kernel/riscv-linux/include/acpi/ghes.h:5,
                 from
/home/guoren/source/kernel/riscv-linux/include/linux/arm_sdei.h:8,
                 from
/home/guoren/source/kernel/riscv-linux/arch/arm64/kernel/asm-offsets.c:10:
/home/guoren/source/kernel/riscv-linux/include/asm-generic/compat.h:87:8:
note: originally defined here
   87 | struct compat_statfs {
      |        ^~~~~~~~~~~~~
make[2]: *** [/home/guoren/source/kernel/riscv-linux/scripts/Makefile.build:121:
arch/arm64/kernel/asm-offsets.s] Error 1
make[1]: *** [/home/guoren/source/kernel/riscv-linux/Makefile:1191:
prepare0] Error 2
make[1]: Leaving directory '/home/guoren/source/kernel/build-arm64'

On Sat, Apr 2, 2022 at 8:53 PM Guo Ren <guoren@kernel.org> wrote:
>
> On Wed, Mar 23, 2022 at 5:00 AM Palmer Dabbelt <palmer@dabbelt.com> wrote:
> >
> > On Tue, 22 Mar 2022 07:39:43 PDT (-0700), guoren@kernel.org wrote:
> > > From: Guo Ren <guoren@linux.alibaba.com>
> > >
> > > Currently, most 64-bit architectures (x86, parisc, powerpc, arm64,
> > > s390, mips, sparc) have supported COMPAT mode. But they all have
> > > history issues and can't use standard linux unistd.h. RISC-V would
> > > be first standard __SYSCALL_COMPAT user of include/uapi/asm-generic
> > > /unistd.h.
> > >
> > > The patchset are based on v5.17-rc8, you can compare rv64-compat
> > > v.s. rv32-native in qemu with following steps:
> > >
> > >  - Prepare rv32 rootfs & fw_jump.bin by buildroot.org
> > >    $ git clone git://git.busybox.net/buildroot
> > >    $ cd buildroot
> > >    $ make qemu_riscv32_virt_defconfig O=qemu_riscv32_virt_defconfig
> > >    $ make -C qemu_riscv32_virt_defconfig
> > >    $ make qemu_riscv64_virt_defconfig O=qemu_riscv64_virt_defconfig
> > >    $ make -C qemu_riscv64_virt_defconfig
> > >    (Got fw_jump.bin & rootfs.ext2 in qemu_riscvXX_virt_defconfig/images)
> > >
> > >  - Prepare Linux rv32 & rv64 Image
> > >    $ git clone git@github.com:c-sky/csky-linux.git -b riscv_compat_v8 linux
> > >    $ cd linux
> > >    $ echo "CONFIG_STRICT_KERNEL_RWX=n" >> arch/riscv/configs/defconfig
> > >    $ echo "CONFIG_STRICT_MODULE_RWX=n" >> arch/riscv/configs/defconfig
> > >    $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ rv32_defconfig
> > >    $ make ARCH=riscv CROSS_COMPILE=riscv32-buildroot-linux-gnu- O=../build-rv32/ Image
> > >    $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ defconfig
> > >    $ make ARCH=riscv CROSS_COMPILE=riscv64-buildroot-linux-gnu- O=../build-rv64/ Image
> > >
> > >  - Prepare Qemu:
> > >    $ git clone https://gitlab.com/qemu-project/qemu.git -b master linux
> > >    $ cd qemu
> > >    $ ./configure --target-list="riscv64-softmmu riscv32-softmmu"
> > >    $ make
> > >
> > > Now let's compare rv64-compat with rv32-native memory footprint with almost the same
> > > defconfig, rootfs, opensbi in one qemu.
> > >
> > >  - Run rv64 with rv32 rootfs in compat mode:
> > >    $ ./build/qemu-system-riscv64 -cpu rv64 -M virt -m 64m -nographic -bios qemu_riscv64_virt_defconfig/images/fw_jump.bin -kernel build-rv64/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0
> > >
> > > QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
> > > OpenSBI v0.9
> > > [    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv64-unknown-linux-gnu-gcc (GCC) 10.2.0, GNU ld (GNU Binutils) 2.37) #96 SMP Tue Dec 28 21:01:55 CST 2021
> > > [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80200000
> > > [    0.000000] Machine model: riscv-virtio,qemu
> > > [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
> > > [    0.000000] printk: bootconsole [sbi0] enabled
> > > [    0.000000] efi: UEFI not found.
> > > [    0.000000] Zone ranges:
> > > [    0.000000]   DMA32    [mem 0x0000000080200000-0x0000000083ffffff]
> > > [    0.000000]   Normal   empty
> > > [    0.000000] Movable zone start for each node
> > > [    0.000000] Early memory node ranges
> > > [    0.000000]   node   0: [mem 0x0000000080200000-0x0000000083ffffff]
> > > [    0.000000] Initmem setup node 0 [mem 0x0000000080200000-0x0000000083ffffff]
> > > [    0.000000] SBI specification v0.2 detected
> > > [    0.000000] SBI implementation ID=0x1 Version=0x9
> > > [    0.000000] SBI TIME extension detected
> > > [    0.000000] SBI IPI extension detected
> > > [    0.000000] SBI RFENCE extension detected
> > > [    0.000000] SBI v0.2 HSM extension detected
> > > [    0.000000] riscv: ISA extensions acdfhimsu
> > > [    0.000000] riscv: ELF capabilities acdfim
> > > [    0.000000] percpu: Embedded 17 pages/cpu s30696 r8192 d30744 u69632
> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15655
> > > [    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
> > > [    0.000000] Dentry cache hash table entries: 8192 (order: 4, 65536 bytes, linear)
> > > [    0.000000] Inode-cache hash table entries: 4096 (order: 3, 32768 bytes, linear)
> > > [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> > > [    0.000000] Virtual kernel memory layout:
> > > [    0.000000]       fixmap : 0xffffffcefee00000 - 0xffffffceff000000   (2048 kB)
> > > [    0.000000]       pci io : 0xffffffceff000000 - 0xffffffcf00000000   (  16 MB)
> > > [    0.000000]      vmemmap : 0xffffffcf00000000 - 0xffffffcfffffffff   (4095 MB)
> > > [    0.000000]      vmalloc : 0xffffffd000000000 - 0xffffffdfffffffff   (65535 MB)
> > > [    0.000000]       lowmem : 0xffffffe000000000 - 0xffffffe003e00000   (  62 MB)
> > > [    0.000000]       kernel : 0xffffffff80000000 - 0xffffffffffffffff   (2047 MB)
> > > [    0.000000] Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved, 0K cma-reserved)
> > > [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> > > [    0.000000] rcu: Hierarchical RCU implementation.
> > > [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
> > > [    0.000000] rcu:     RCU debug extended QS entry/exit.
> > > [    0.000000]  Tracing variant of Tasks RCU enabled.
> > > [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> > > [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
> > > [    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
> > > [    0.000000] riscv-intc: 64 local interrupts mapped
> > > [    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
> > > ...
> > > Welcome to Buildroot
> > > buildroot login: root
> > > # cat /proc/cpuinfo
> > > processor       : 0
> > > hart            : 0
> > > isa             : rv64imafdcsuh
> > > mmu             : sv48
> > >
> > > # file /bin/busybox
> > > /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
> > > # ca[   78.386630] random: fast init done
> > > # cat /proc/meminfo
> > > MemTotal:          53076 kB
> > > MemFree:           40264 kB
> > > MemAvailable:      40244 kB
> > > Buffers:             236 kB
> > > Cached:             1560 kB
> > > SwapCached:            0 kB
> > > Active:             1700 kB
> > > Inactive:            516 kB
> > > Active(anon):         40 kB
> > > Inactive(anon):      424 kB
> > > Active(file):       1660 kB
> > > Inactive(file):       92 kB
> > > Unevictable:           0 kB
> > > Mlocked:               0 kB
> > > SwapTotal:             0 kB
> > > SwapFree:              0 kB
> > > Dirty:                 0 kB
> > > Writeback:             0 kB
> > > AnonPages:           444 kB
> > > Mapped:             1188 kB
> > > Shmem:                44 kB
> > > KReclaimable:        952 kB
> > > Slab:               5744 kB
> > > SReclaimable:        952 kB
> > > SUnreclaim:         4792 kB
> > > KernelStack:         624 kB
> > > PageTables:          156 kB
> > > NFS_Unstable:          0 kB
> > > Bounce:                0 kB
> > > WritebackTmp:          0 kB
> > > CommitLimit:       26536 kB
> > > Committed_AS:       1748 kB
> > > VmallocTotal:   67108863 kB
> > > VmallocUsed:         652 kB
> > > VmallocChunk:          0 kB
> > > Percpu:               80 kB
> > > #
> > >
> > >  - Run rv32 with rv32 rootfs:
> > >    $ ./build/qemu-system-riscv32 -cpu rv32 -M virt -m 64m -nographic -bios qemu_riscv32_virt_defconfig/images/fw_jump.bin -kernel build-rv32/Image -drive file qemu_riscv32_virt_defconfig/images/rootfs.ext2,format=raw,id=hd0 -device virtio-blk-device,drive=hd0 -append "rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi" -netdev user,id=net0 -device virtio-net-device,netdev=net0
> > >
> > > QEMU emulator version 6.2.50 (v6.2.0-29-g196d7182c8)
> > > OpenSBI v0.9
> > > [    0.000000] Linux version 5.16.0-rc6-00017-g750f87086bdd-dirty (guoren@guoren-Z87-HD3) (riscv32-buildroot-linux-gnu-gcc.br_real (Buildroot 2021.11-201-g7600ca7960-dirty) 10.3.0, GNU ld (GNU Binutils) 2.36.1) #7 SMP Tue Dec 28 21:02:21 CST 2021
> > > [    0.000000] OF: fdt: Ignoring memory range 0x80000000 - 0x80400000
> > > [    0.000000] Machine model: riscv-virtio,qemu
> > > [    0.000000] earlycon: sbi0 at I/O port 0x0 (options '')
> > > [    0.000000] printk: bootconsole [sbi0] enabled
> > > [    0.000000] efi: UEFI not found.
> > > [    0.000000] Zone ranges:
> > > [    0.000000]   Normal   [mem 0x0000000080400000-0x0000000083ffffff]
> > > [    0.000000] Movable zone start for each node
> > > [    0.000000] Early memory node ranges
> > > [    0.000000]   node   0: [mem 0x0000000080400000-0x0000000083ffffff]
> > > [    0.000000] Initmem setup node 0 [mem 0x0000000080400000-0x0000000083ffffff]
> > > [    0.000000] SBI specification v0.2 detected
> > > [    0.000000] SBI implementation ID=0x1 Version=0x9
> > > [    0.000000] SBI TIME extension detected
> > > [    0.000000] SBI IPI extension detected
> > > [    0.000000] SBI RFENCE extension detected
> > > [    0.000000] SBI v0.2 HSM extension detected
> > > [    0.000000] riscv: ISA extensions acdfhimsu
> > > [    0.000000] riscv: ELF capabilities acdfim
> > > [    0.000000] percpu: Embedded 12 pages/cpu s16600 r8192 d24360 u49152
> > > [    0.000000] Built 1 zonelists, mobility grouping on.  Total pages: 15240
> > > [    0.000000] Kernel command line: rootwait root=/dev/vda ro console=ttyS0 earlycon=sbi
> > > [    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes, linear)
> > > [    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes, linear)
> > > [    0.000000] mem auto-init: stack:off, heap alloc:off, heap free:off
> > > [    0.000000] Virtual kernel memory layout:
> > > [    0.000000]       fixmap : 0x9dc00000 - 0x9e000000   (4096 kB)
> > > [    0.000000]       pci io : 0x9e000000 - 0x9f000000   (  16 MB)
> > > [    0.000000]      vmemmap : 0x9f000000 - 0x9fffffff   (  15 MB)
> > > [    0.000000]      vmalloc : 0xa0000000 - 0xbfffffff   ( 511 MB)
> > > [    0.000000]       lowmem : 0xc0000000 - 0xc3c00000   (  60 MB)
> > > [    0.000000] Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss, 9516K reserved, 0K cma-reserved)
> > > [    0.000000] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1
> > > [    0.000000] rcu: Hierarchical RCU implementation.
> > > [    0.000000] rcu:     RCU restricting CPUs from NR_CPUS=8 to nr_cpu_ids=1.
> > > [    0.000000] rcu:     RCU debug extended QS entry/exit.
> > > [    0.000000]  Tracing variant of Tasks RCU enabled.
> > > [    0.000000] rcu: RCU calculated value of scheduler-enlistment delay is 25 jiffies.
> > > [    0.000000] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1
> > > [    0.000000] NR_IRQS: 64, nr_irqs: 64, preallocated irqs: 0
> > > [    0.000000] riscv-intc: 32 local interrupts mapped
> > > [    0.000000] plic: plic@c000000: mapped 53 interrupts with 1 handlers for 2 contexts.
> > > ...
> > > Welcome to Buildroot
> > > buildroot login: root
> > > # cat /proc/cpuinfo
> > > processor       : 0
> > > hart            : 0
> > > isa             : rv32imafdcsuh
> > > mmu             : sv32
> > >
> > > # file /bin/busybox
> > > /bin/busybox: setuid ELF 32-bit LSB shared object, UCB RISC-V, version 1 (SYSV), dynamically linked, interpreter /lib/ld-linux-riscv32-ilp32d.so.1, for GNU/Linux 5.15.0, stripped
> > > [   79.320589] random: fast init done
> > > # cat /proc/meminfo
> > > MemTotal:          52176 kB
> > > MemFree:           41012 kB
> > > MemAvailable:      42176 kB
> > > Buffers:             644 kB
> > > Cached:             2724 kB
> > > SwapCached:            0 kB
> > > Active:             3128 kB
> > > Inactive:            752 kB
> > > Active(anon):         40 kB
> > > Inactive(anon):      516 kB
> > > Active(file):       3088 kB
> > > Inactive(file):      236 kB
> > > Unevictable:           0 kB
> > > Mlocked:               0 kB
> > > SwapTotal:             0 kB
> > > SwapFree:              0 kB
> > > Dirty:                 4 kB
> > > Writeback:             0 kB
> > > AnonPages:           556 kB
> > > Mapped:             2172 kB
> > > Shmem:                44 kB
> > > KReclaimable:        656 kB
> > > Slab:               3684 kB
> > > SReclaimable:        656 kB
> > > SUnreclaim:         3028 kB
> > > KernelStack:         312 kB
> > > PageTables:           88 kB
> > > NFS_Unstable:          0 kB
> > > Bounce:                0 kB
> > > WritebackTmp:          0 kB
> > > CommitLimit:       26088 kB
> > > Committed_AS:       2088 kB
> > > VmallocTotal:     524287 kB
> > > VmallocUsed:          12 kB
> > > VmallocChunk:          0 kB
> > > Percpu:               60 kB
> > > #
> > >
> > >  Some conclusions:
> > >  - kernel statics:
> > >    64: Memory: 52788K/63488K available (6184K kernel code, 888K rwdata, 1917K rodata, 294K init, 297K bss, 10700K reserved)
> > >    32: Memory: 51924K/61440K available (6117K kernel code, 695K rwdata, 1594K rodata, 255K init, 241K bss,  9516K reserved)
> > >    rv32 better than rv64:                  1%               22%           17%          13%        19%         11%
> > >    The code size is very similar, but data size rv32 would be better.
> > >
> > >  - rv32 kernel runtime KernelStack, Slab... are smaller,
> > >    rv64: MemTotal: 53076 kB,        MemFree: 40264 kB
> > >    rv32: MemTotal: 52176 + 2048 kB, MemFree: 41012  + 2048 kB
> > >    rv32 better than rv64:       2%                         6%
> > >
> > >    (Because opensbi problem, we could add another 2MB for rv32.)
> > >    Overall in 64MB memory situation, rv64-compat is 6% worse than rv32-native
> > >    at memory footprint. If the userspace memory usage increases, I think
> > >    the gap will be further reduced.
> > >
> > > Changes in v9:
> > >  - Fixup rv32 call rv64 segment fault
> > >  - Ready for 5.18
> >
> > Thanks.  I'd also seen some arm64 autobuilder failures, not sure if
> > those got fixed as I don't see anything specificlly listed in here
> > (sorry if I just missed it).
> >
> > I've gone ahead and put this on palmer/riscv-compat, I'm going to let it
> > sit at least overnight before putting it on for-next proper.  It's a
> > big one and the autobuilders seem to find stuff over there, I don't want
> > to break any of the other ports.  IIRC you were getting CC'd on the
> > build failures I was seeing.
> I couldn't find that, could you give me a link, thank you.
>
> >
> > If it's clean I'll merge it into for-next propely.  It's passing my
> > staging merge tests, but I don't yet have anything specifically for
> > compat -- at least it's not causing any regressions, though.
> >
> > >
> > > Changes in v8:
> > >  - Enhanced elf_check_arch with EI_CLASS
> > >  - Fixup SR_UXL doesn't exist in CONFIG_32BIT
> > >  - Add Tested-by with Heiko
> > >  - Update qemu compile tips with upstream repo
> > >
> > > Changes in v7:
> > >  - Re-construct compat_vdso/Makefile
> > >  - Fixup disable COMPAT compile error by csr.h's macro.
> > >  - Optimize coding convention for lo/hi in compat.h
> > >
> > > Changes in v6:
> > >  - Rebase on linux-5.17-rc5
> > >  - Optimize hw capability check for elf
> > >  - Optimize comment in thread_info.h
> > >  - Optimize start_thread with SR_UXL setting
> > >  - Optimize vdso.c with direct panic
> > >
> > > Changes in v5:
> > >  - Rebase on linux-5.17-rc2
> > >  - Include consolidate the fcntl patches by Christoph Hellwig
> > >  - Remove F_GETLK64/F_SETLK64/F_SETLKW64 from asm/compat.h
> > >  - Change COMPAT_RLIM_INFINITY from 0x7fffffff to 0xffffffff
> > >  - Bring back "Add hw-cap detect in setup_arch patch" in v1
> > >
> > > Changes in v4:
> > >  - Rebase on linux-5.17-rc1
> > >  - Optimize compat_sys_call_table implementation with Arnd's advice
> > >  - Add reviewed-by for Arnd. Thx :)
> > >  - Remove FIXME comment in elf.h
> > >  - Optimize Cleanup duplicate definitions in compat.h with Arnd's advice
> > >
> > > Changes in v3:
> > >  - Rebase on newest master (pre linux-5.17-rc1)
> > >  - Using newest qemu version v7 for test
> > >  - Remove fcntl common modification
> > >  - Fixup SET_PERSONALITY in elf.h by Arnd
> > >  - Fixup KVM Kconfig
> > >  - Update Acked-by & Reviewed-by
> > >
> > > Changes in v2:
> > >  - Add __ARCH_WANT_COMPAT_STAT suggested
> > >  - Cleanup fcntl compatduplicate definitions
> > >  - Cleanup compat.h
> > >  - Move rv32_defconfig into Makefile
> > >  - Fixup rv64 rootfs boot failed, remove hw_compat_mode_detect
> > >  - Move SYSVIPC_COMPAT into init/Kconfig
> > >  - Simplify compat_elf_check
> > >
> > > Christoph Hellwig (3):
> > >   uapi: simplify __ARCH_FLOCK{,64}_PAD a little
> > >   uapi: always define F_GETLK64/F_SETLK64/F_SETLKW64 in fcntl.h
> > >   compat: consolidate the compat_flock{,64} definition
> > >
> > > Guo Ren (17):
> > >   kconfig: Add SYSVIPC_COMPAT for all architectures
> > >   fs: stat: compat: Add __ARCH_WANT_COMPAT_STAT
> > >   asm-generic: compat: Cleanup duplicate definitions
> > >   syscalls: compat: Fix the missing part for __SYSCALL_COMPAT
> > >   riscv: Fixup difference with defconfig
> > >   riscv: compat: Add basic compat data type implementation
> > >   riscv: compat: Re-implement TASK_SIZE for COMPAT_32BIT
> > >   riscv: compat: syscall: Add compat_sys_call_table implementation
> > >   riscv: compat: syscall: Add entry.S implementation
> > >   riscv: compat: process: Add UXL_32 support in start_thread
> > >   riscv: compat: Add elf.h implementation
> > >   riscv: compat: Add hw capability check for elf
> > >   riscv: compat: vdso: Add COMPAT_VDSO base code implementation
> > >   riscv: compat: vdso: Add setup additional pages implementation
> > >   riscv: compat: signal: Add rt_frame implementation
> > >   riscv: compat: ptrace: Add compat_arch_ptrace implement
> > >   riscv: compat: Add COMPAT Kbuild skeletal support
> > >
> > >  arch/arm64/Kconfig                            |   4 -
> > >  arch/arm64/include/asm/compat.h               |  91 +------
> > >  arch/arm64/include/asm/unistd.h               |   1 +
> > >  arch/mips/Kconfig                             |   5 -
> > >  arch/mips/include/asm/compat.h                |  41 +--
> > >  arch/mips/include/asm/unistd.h                |   2 +
> > >  arch/mips/include/uapi/asm/fcntl.h            |  30 +--
> > >  arch/parisc/Kconfig                           |   4 -
> > >  arch/parisc/include/asm/compat.h              |  45 +---
> > >  arch/parisc/include/asm/unistd.h              |   1 +
> > >  arch/powerpc/Kconfig                          |   5 -
> > >  arch/powerpc/include/asm/compat.h             |  50 +---
> > >  arch/powerpc/include/asm/unistd.h             |   1 +
> > >  arch/riscv/Kconfig                            |  19 ++
> > >  arch/riscv/Makefile                           |   9 +
> > >  arch/riscv/configs/rv32_defconfig             | 135 ----------
> > >  arch/riscv/include/asm/compat.h               | 129 ++++++++++
> > >  arch/riscv/include/asm/csr.h                  |   7 +
> > >  arch/riscv/include/asm/elf.h                  |  50 +++-
> > >  arch/riscv/include/asm/mmu.h                  |   1 +
> > >  arch/riscv/include/asm/pgtable.h              |  13 +-
> > >  arch/riscv/include/asm/processor.h            |   6 +-
> > >  arch/riscv/include/asm/syscall.h              |   1 +
> > >  arch/riscv/include/asm/thread_info.h          |   1 +
> > >  arch/riscv/include/asm/unistd.h               |  11 +
> > >  arch/riscv/include/asm/vdso.h                 |   9 +
> > >  arch/riscv/include/uapi/asm/unistd.h          |   2 +-
> > >  arch/riscv/kernel/Makefile                    |   3 +
> > >  arch/riscv/kernel/compat_signal.c             | 243 ++++++++++++++++++
> > >  arch/riscv/kernel/compat_syscall_table.c      |  19 ++
> > >  arch/riscv/kernel/compat_vdso/.gitignore      |   2 +
> > >  arch/riscv/kernel/compat_vdso/Makefile        |  78 ++++++
> > >  arch/riscv/kernel/compat_vdso/compat_vdso.S   |   8 +
> > >  .../kernel/compat_vdso/compat_vdso.lds.S      |   3 +
> > >  arch/riscv/kernel/compat_vdso/flush_icache.S  |   3 +
> > >  .../compat_vdso/gen_compat_vdso_offsets.sh    |   5 +
> > >  arch/riscv/kernel/compat_vdso/getcpu.S        |   3 +
> > >  arch/riscv/kernel/compat_vdso/note.S          |   3 +
> > >  arch/riscv/kernel/compat_vdso/rt_sigreturn.S  |   3 +
> > >  arch/riscv/kernel/entry.S                     |  18 +-
> > >  arch/riscv/kernel/process.c                   |  37 +++
> > >  arch/riscv/kernel/ptrace.c                    |  87 ++++++-
> > >  arch/riscv/kernel/signal.c                    |  13 +-
> > >  arch/riscv/kernel/sys_riscv.c                 |   6 +-
> > >  arch/riscv/kernel/vdso.c                      | 105 +++++---
> > >  arch/riscv/kernel/vdso/vdso.S                 |   6 +-
> > >  arch/s390/Kconfig                             |   3 -
> > >  arch/s390/include/asm/compat.h                |  99 +------
> > >  arch/s390/include/asm/unistd.h                |   1 +
> > >  arch/sparc/Kconfig                            |   5 -
> > >  arch/sparc/include/asm/compat.h               |  61 ++---
> > >  arch/sparc/include/asm/unistd.h               |   1 +
> > >  arch/x86/Kconfig                              |   4 -
> > >  arch/x86/include/asm/compat.h                 | 104 ++------
> > >  arch/x86/include/asm/unistd.h                 |   1 +
> > >  fs/open.c                                     |  24 ++
> > >  fs/read_write.c                               |  16 ++
> > >  fs/stat.c                                     |   2 +-
> > >  fs/sync.c                                     |   9 +
> > >  include/asm-generic/compat.h                  | 113 ++++++++
> > >  include/linux/compat.h                        |  68 +++++
> > >  include/uapi/asm-generic/fcntl.h              |  23 +-
> > >  include/uapi/asm-generic/unistd.h             |   4 +-
> > >  init/Kconfig                                  |   4 +
> > >  mm/fadvise.c                                  |  11 +
> > >  mm/readahead.c                                |   7 +
> > >  tools/include/uapi/asm-generic/fcntl.h        |  21 +-
> > >  tools/include/uapi/asm-generic/unistd.h       |   4 +-
> > >  68 files changed, 1205 insertions(+), 698 deletions(-)
> > >  delete mode 100644 arch/riscv/configs/rv32_defconfig
> > >  create mode 100644 arch/riscv/include/asm/compat.h
> > >  create mode 100644 arch/riscv/kernel/compat_signal.c
> > >  create mode 100644 arch/riscv/kernel/compat_syscall_table.c
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/.gitignore
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/Makefile
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.S
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/compat_vdso.lds.S
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/flush_icache.S
> > >  create mode 100755 arch/riscv/kernel/compat_vdso/gen_compat_vdso_offsets.sh
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/getcpu.S
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/note.S
> > >  create mode 100644 arch/riscv/kernel/compat_vdso/rt_sigreturn.S
>
>
>
> --
> Best Regards
>  Guo Ren
>
> ML: https://lore.kernel.org/linux-csky/



-- 
Best Regards
 Guo Ren

ML: https://lore.kernel.org/linux-csky/