These new helpers will be needed for pud entry updates soon. Introduce
these helpers by referencing the pmd ones. Namely:
- pudp_invalidate()
- pud_modify()
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Signed-off-by: Peter Xu <peterx@redhat.com>
---
arch/x86/include/asm/pgtable.h | 55 +++++++++++++++++++++++++++++-----
arch/x86/mm/pgtable.c | 11 +++++++
2 files changed, 58 insertions(+), 8 deletions(-)
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index cdf044c2ad6e..701593c53f3b 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -782,6 +782,12 @@ static inline pmd_t pmd_mkinvalid(pmd_t pmd)
__pgprot(pmd_flags(pmd) & ~(_PAGE_PRESENT|_PAGE_PROTNONE)));
}
+static inline pud_t pud_mkinvalid(pud_t pud)
+{
+ return pfn_pud(pud_pfn(pud),
+ __pgprot(pud_flags(pud) & ~(_PAGE_PRESENT|_PAGE_PROTNONE)));
+}
+
static inline u64 flip_protnone_guard(u64 oldval, u64 val, u64 mask);
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
@@ -829,14 +835,8 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
pmd_result = __pmd(val);
/*
- * To avoid creating Write=0,Dirty=1 PMDs, pte_modify() needs to avoid:
- * 1. Marking Write=0 PMDs Dirty=1
- * 2. Marking Dirty=1 PMDs Write=0
- *
- * The first case cannot happen because the _PAGE_CHG_MASK will filter
- * out any Dirty bit passed in newprot. Handle the second case by
- * going through the mksaveddirty exercise. Only do this if the old
- * value was Write=1 to avoid doing this on Shadow Stack PTEs.
+ * Avoid creating shadow stack PMD by accident. See comment in
+ * pte_modify().
*/
if (oldval & _PAGE_RW)
pmd_result = pmd_mksaveddirty(pmd_result);
@@ -846,6 +846,29 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot)
return pmd_result;
}
+static inline pud_t pud_modify(pud_t pud, pgprot_t newprot)
+{
+ pudval_t val = pud_val(pud), oldval = val;
+ pud_t pud_result;
+
+ val &= _HPAGE_CHG_MASK;
+ val |= check_pgprot(newprot) & ~_HPAGE_CHG_MASK;
+ val = flip_protnone_guard(oldval, val, PHYSICAL_PUD_PAGE_MASK);
+
+ pud_result = __pud(val);
+
+ /*
+ * Avoid creating shadow stack PUD by accident. See comment in
+ * pte_modify().
+ */
+ if (oldval & _PAGE_RW)
+ pud_result = pud_mksaveddirty(pud_result);
+ else
+ pud_result = pud_clear_saveddirty(pud_result);
+
+ return pud_result;
+}
+
/*
* mprotect needs to preserve PAT and encryption bits when updating
* vm_page_prot
@@ -1384,10 +1407,26 @@ static inline pmd_t pmdp_establish(struct vm_area_struct *vma,
}
#endif
+static inline pud_t pudp_establish(struct vm_area_struct *vma,
+ unsigned long address, pud_t *pudp, pud_t pud)
+{
+ page_table_check_pud_set(vma->vm_mm, pudp, pud);
+ if (IS_ENABLED(CONFIG_SMP)) {
+ return xchg(pudp, pud);
+ } else {
+ pud_t old = *pudp;
+ WRITE_ONCE(*pudp, pud);
+ return old;
+ }
+}
+
#define __HAVE_ARCH_PMDP_INVALIDATE_AD
extern pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma,
unsigned long address, pmd_t *pmdp);
+pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
+ pud_t *pudp);
+
/*
* Page table pages are page-aligned. The lower half of the top
* level is used for userspace and the top half for the kernel.
diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index 564b8945951e..9d97a1b99160 100644
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -641,6 +641,17 @@ pmd_t pmdp_invalidate_ad(struct vm_area_struct *vma, unsigned long address,
}
#endif
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+pud_t pudp_invalidate(struct vm_area_struct *vma, unsigned long address,
+ pud_t *pudp)
+{
+ VM_WARN_ON_ONCE(!pud_present(*pudp));
+ pud_t old = pudp_establish(vma, address, pudp, pud_mkinvalid(*pudp));
+ flush_pud_tlb_range(vma, address, address + HPAGE_PUD_SIZE);
+ return old;
+}
+#endif
+
/**
* reserve_top_address - reserves a hole in the top of kernel address space
* @reserve - size of hole to reserve
--
2.45.0Hi Peter,
kernel test robot noticed the following build errors:
[auto build test ERROR on akpm-mm/mm-everything]
url: https://github.com/intel-lab-lkp/linux/commits/Peter-Xu/mm-dax-Dump-start-address-in-fault-handler/20240705-013812
base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link: https://lore.kernel.org/r/20240703212918.2417843-8-peterx%40redhat.com
patch subject: [PATCH v2 7/8] mm/x86: Add missing pud helpers
config: i386-randconfig-011-20240706 (https://download.01.org/0day-ci/archive/20240706/202407061716.WH5NMiL2-lkp@intel.com/config)
compiler: gcc-11 (Ubuntu 11.4.0-4ubuntu1) 11.4.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240706/202407061716.WH5NMiL2-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202407061716.WH5NMiL2-lkp@intel.com/
All errors (new ones prefixed by >>):
In file included from arch/x86/include/asm/atomic.h:8,
from include/linux/atomic.h:7,
from include/linux/jump_label.h:256,
from include/linux/static_key.h:1,
from arch/x86/include/asm/nospec-branch.h:6,
from arch/x86/include/asm/irqflags.h:9,
from include/linux/irqflags.h:18,
from include/linux/spinlock.h:59,
from include/linux/mmzone.h:8,
from include/linux/gfp.h:7,
from include/linux/mm.h:7,
from arch/x86/mm/pgtable.c:2:
In function 'pudp_establish',
inlined from 'pudp_invalidate' at arch/x86/mm/pgtable.c:649:14:
>> arch/x86/include/asm/cmpxchg.h:67:25: error: call to '__xchg_wrong_size' declared with attribute error: Bad argument size for xchg
67 | __ ## op ## _wrong_size(); \
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/x86/include/asm/cmpxchg.h:78:33: note: in expansion of macro '__xchg_op'
78 | #define arch_xchg(ptr, v) __xchg_op((ptr), (v), xchg, "")
| ^~~~~~~~~
include/linux/atomic/atomic-arch-fallback.h:12:18: note: in expansion of macro 'arch_xchg'
12 | #define raw_xchg arch_xchg
| ^~~~~~~~~
include/linux/atomic/atomic-instrumented.h:4758:9: note: in expansion of macro 'raw_xchg'
4758 | raw_xchg(__ai_ptr, __VA_ARGS__); \
| ^~~~~~~~
arch/x86/include/asm/pgtable.h:1415:24: note: in expansion of macro 'xchg'
1415 | return xchg(pudp, pud);
| ^~~~
vim +/__xchg_wrong_size +67 arch/x86/include/asm/cmpxchg.h
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 37
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 38 /*
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 39 * An exchange-type operation, which takes a value and a pointer, and
7f5281ae8a8e7f8 Li Zhong 2013-04-25 40 * returns the old value.
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 41 */
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 42 #define __xchg_op(ptr, arg, op, lock) \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 43 ({ \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 44 __typeof__ (*(ptr)) __ret = (arg); \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 45 switch (sizeof(*(ptr))) { \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 46 case __X86_CASE_B: \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 47 asm volatile (lock #op "b %b0, %1\n" \
2ca052a3710fac2 Jeremy Fitzhardinge 2012-04-02 48 : "+q" (__ret), "+m" (*(ptr)) \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 49 : : "memory", "cc"); \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 50 break; \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 51 case __X86_CASE_W: \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 52 asm volatile (lock #op "w %w0, %1\n" \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 53 : "+r" (__ret), "+m" (*(ptr)) \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 54 : : "memory", "cc"); \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 55 break; \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 56 case __X86_CASE_L: \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 57 asm volatile (lock #op "l %0, %1\n" \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 58 : "+r" (__ret), "+m" (*(ptr)) \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 59 : : "memory", "cc"); \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 60 break; \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 61 case __X86_CASE_Q: \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 62 asm volatile (lock #op "q %q0, %1\n" \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 63 : "+r" (__ret), "+m" (*(ptr)) \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 64 : : "memory", "cc"); \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 65 break; \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 66 default: \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 @67 __ ## op ## _wrong_size(); \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 68 } \
31a8394e069e47d Jeremy Fitzhardinge 2011-09-30 69 __ret; \
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 70 })
e9826380d83d1bd Jeremy Fitzhardinge 2011-08-18 71
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
On Sat, Jul 06, 2024 at 05:16:15PM +0800, kernel test robot wrote: > Hi Peter, > > kernel test robot noticed the following build errors: > > [auto build test ERROR on akpm-mm/mm-everything] > > url: https://github.com/intel-lab-lkp/linux/commits/Peter-Xu/mm-dax-Dump-start-address-in-fault-handler/20240705-013812 > base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything > patch link: https://lore.kernel.org/r/20240703212918.2417843-8-peterx%40redhat.com > patch subject: [PATCH v2 7/8] mm/x86: Add missing pud helpers > config: i386-randconfig-011-20240706 (https://download.01.org/0day-ci/archive/20240706/202407061716.WH5NMiL2-lkp@intel.com/config) > compiler: gcc-11 (Ubuntu 11.4.0-4ubuntu1) 11.4.0 > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240706/202407061716.WH5NMiL2-lkp@intel.com/reproduce) > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > the same patch/commit), kindly add following tags > | Reported-by: kernel test robot <lkp@intel.com> > | Closes: https://lore.kernel.org/oe-kbuild-all/202407061716.WH5NMiL2-lkp@intel.com/ > > All errors (new ones prefixed by >>): > > In file included from arch/x86/include/asm/atomic.h:8, > from include/linux/atomic.h:7, > from include/linux/jump_label.h:256, > from include/linux/static_key.h:1, > from arch/x86/include/asm/nospec-branch.h:6, > from arch/x86/include/asm/irqflags.h:9, > from include/linux/irqflags.h:18, > from include/linux/spinlock.h:59, > from include/linux/mmzone.h:8, > from include/linux/gfp.h:7, > from include/linux/mm.h:7, > from arch/x86/mm/pgtable.c:2: > In function 'pudp_establish', > inlined from 'pudp_invalidate' at arch/x86/mm/pgtable.c:649:14: > >> arch/x86/include/asm/cmpxchg.h:67:25: error: call to '__xchg_wrong_size' declared with attribute error: Bad argument size for xchg > 67 | __ ## op ## _wrong_size(); \ > | ^~~~~~~~~~~~~~~~~~~~~~~~~ > arch/x86/include/asm/cmpxchg.h:78:33: note: in expansion of macro '__xchg_op' > 78 | #define arch_xchg(ptr, v) __xchg_op((ptr), (v), xchg, "") > | ^~~~~~~~~ > include/linux/atomic/atomic-arch-fallback.h:12:18: note: in expansion of macro 'arch_xchg' > 12 | #define raw_xchg arch_xchg > | ^~~~~~~~~ > include/linux/atomic/atomic-instrumented.h:4758:9: note: in expansion of macro 'raw_xchg' > 4758 | raw_xchg(__ai_ptr, __VA_ARGS__); \ > | ^~~~~~~~ > arch/x86/include/asm/pgtable.h:1415:24: note: in expansion of macro 'xchg' > 1415 | return xchg(pudp, pud); > | ^~~~ So this is the PAE paging on i386 which indeed didn't get covered in my testsuite.. where it only covered allno/alldef which were always 2lvls. I'll fix it when I repost, I'll add PAE into my harness too. -- Peter Xu
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