From: Jens Remus <jremus@linux.ibm.com>
Commit 7cd50cbe4ca3 ("pc-bios/s390-ccw: Don't use __bss_start with the
"larl" instruction") introduced the address constant bss_start_literal
for __bss_start in the .text section, which introduced a relocation in
code (i.e. TEXTREL). The dedicated constant is required, as __bss_start
may not necessarily be aligned on a 2-byte boundary (see subject commit
for details).
Move the constant to the .data section to get rid of the relocation in
the .text section. Add the linker option -z text to prevent TEXTRELs to
get introduced in the future.
Note that the R_390_RELATIVE relocations are taken care of by function
glue() in include/hw/elf_ops.h.inc introduced by commit 5dce07e1cb67
("elf-loader: Provide the possibility to relocate s390 ELF files").
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Marc Hartmayer <mhartmay@linux.ibm.com>
---
pc-bios/s390-ccw/Makefile | 2 +-
pc-bios/s390-ccw/start.S | 7 +++++--
2 files changed, 6 insertions(+), 3 deletions(-)
diff --git a/pc-bios/s390-ccw/Makefile b/pc-bios/s390-ccw/Makefile
index 6207911b53aa..ab6bd1edf41e 100644
--- a/pc-bios/s390-ccw/Makefile
+++ b/pc-bios/s390-ccw/Makefile
@@ -40,7 +40,7 @@ EXTRA_CFLAGS += -ffreestanding -fno-delete-null-pointer-checks -fno-common -fPIE
EXTRA_CFLAGS += -fwrapv -fno-strict-aliasing -fno-asynchronous-unwind-tables
EXTRA_CFLAGS += -msoft-float
EXTRA_CFLAGS += -std=gnu99
-LDFLAGS += -Wl,-pie -nostdlib -z noexecstack
+LDFLAGS += -Wl,-pie -nostdlib -z noexecstack -z text
cc-test = $(CC) -Werror $1 -c -o /dev/null -xc /dev/null >/dev/null 2>/dev/null
cc-option = if $(call cc-test, $1); then \
diff --git a/pc-bios/s390-ccw/start.S b/pc-bios/s390-ccw/start.S
index 576fc12c06e8..b70213e41246 100644
--- a/pc-bios/s390-ccw/start.S
+++ b/pc-bios/s390-ccw/start.S
@@ -113,8 +113,6 @@ io_new_code:
br %r14
.balign 8
-bss_start_literal:
- .quad __bss_start
disabled_wait_psw:
.quad 0x0002000180000000,0x0000000000000000
enabled_wait_psw:
@@ -124,6 +122,11 @@ external_new_mask:
io_new_mask:
.quad 0x0000000180000000
+.data
+ .balign 8
+bss_start_literal:
+ .quad __bss_start
+
.bss
.balign 8
stack:
--
2.43.0