| Message ID | 20240703212918.2417843-8-peterx@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm/mprotect: Fix dax puds | expand |
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);
| ^~~~
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
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
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(-)