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authorAlexander Potapenko <glider@google.com>2022-11-10 12:35:41 +0100
committerAndrew Morton <akpm@linux-foundation.org>2022-12-01 00:59:02 +0100
commitf6fbb8b23b8155a6f7af1349b4595d0373167636 (patch)
treebdc32d357368304ff25ccaf0da978c53f2caa20d
parentfolio-compat: remove try_to_release_page() (diff)
downloadlinux-f6fbb8b23b8155a6f7af1349b4595d0373167636.tar.xz
linux-f6fbb8b23b8155a6f7af1349b4595d0373167636.zip
Revert "kmsan: unpoison @tlb in arch_tlb_gather_mmu()"
This reverts commit ac801e7e252c5588325e3c983c7d4167fc68c024. The patch in question was picked to -mm from the KMSAN v6 patch series (https://lore.kernel.org/linux-mm/20220905122452.2258262-1-glider@google.com/) and sneaked into mainline despite its removal from the v7 series (https://lore.kernel.org/linux-mm/20220915150417.722975-1-glider@google.com/) Currently KMSAN does not warn about origin chains hitting the maximum depth, so keeping @tlb poisoned won't result in any inconveniences. Link: https://lkml.kernel.org/r/20221110113541.1844156-1-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Marco Elver <elver@google.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-rw-r--r--mm/mmu_gather.c10
1 files changed, 0 insertions, 10 deletions
diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
index dd1f8ca40cb5..8247553a69c2 100644
--- a/mm/mmu_gather.c
+++ b/mm/mmu_gather.c
@@ -1,7 +1,6 @@
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/kernel.h>
-#include <linux/kmsan-checks.h>
#include <linux/mmdebug.h>
#include <linux/mm_types.h>
#include <linux/mm_inline.h>
@@ -299,15 +298,6 @@ void tlb_flush_mmu(struct mmu_gather *tlb)
static void __tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
bool fullmm)
{
- /*
- * struct mmu_gather contains 7 1-bit fields packed into a 32-bit
- * unsigned int value. The remaining 25 bits remain uninitialized
- * and are never used, but KMSAN updates the origin for them in
- * zap_pXX_range() in mm/memory.c, thus creating very long origin
- * chains. This is technically correct, but consumes too much memory.
- * Unpoisoning the whole structure will prevent creating such chains.
- */
- kmsan_unpoison_memory(tlb, sizeof(*tlb));
tlb->mm = mm;
tlb->fullmm = fullmm;