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| author | Andrey Ryabinin <ryabinin.a.a@gmail.com> | 2022-10-28 00:31:04 +0300 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2022-12-15 10:37:26 -0800 |
| commit | 3f148f3318140035e87decc1214795ff0755757b (patch) | |
| tree | 97abaf0e5e5aa0fa4b5bf651a2d6a72041956d7e /arch/x86/include | |
| parent | 30a0b95b1335e12efef89dd78518ed3e4a71a763 (diff) | |
| download | linux-3f148f3318140035e87decc1214795ff0755757b.tar.bz2 | |
x86/kasan: Map shadow for percpu pages on demand
KASAN maps shadow for the entire CPU-entry-area:
[CPU_ENTRY_AREA_BASE, CPU_ENTRY_AREA_BASE + CPU_ENTRY_AREA_MAP_SIZE]
This will explode once the per-cpu entry areas are randomized since it
will increase CPU_ENTRY_AREA_MAP_SIZE to 512 GB and KASAN fails to
allocate shadow for such big area.
Fix this by allocating KASAN shadow only for really used cpu entry area
addresses mapped by cea_map_percpu_pages()
Thanks to the 0day folks for finding and reporting this to be an issue.
[ dhansen: tweak changelog since this will get committed before peterz's
actual cpu-entry-area randomization ]
Signed-off-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Yujie Liu <yujie.liu@intel.com>
Cc: kernel test robot <yujie.liu@intel.com>
Link: https://lore.kernel.org/r/202210241508.2e203c3d-yujie.liu@intel.com
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/kasan.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/include/asm/kasan.h b/arch/x86/include/asm/kasan.h index 13e70da38bed..de75306b932e 100644 --- a/arch/x86/include/asm/kasan.h +++ b/arch/x86/include/asm/kasan.h @@ -28,9 +28,12 @@ #ifdef CONFIG_KASAN void __init kasan_early_init(void); void __init kasan_init(void); +void __init kasan_populate_shadow_for_vaddr(void *va, size_t size, int nid); #else static inline void kasan_early_init(void) { } static inline void kasan_init(void) { } +static inline void kasan_populate_shadow_for_vaddr(void *va, size_t size, + int nid) { } #endif #endif |