The patch titled
Subject: kasan,kmsan: remove __GFP_KSWAPD_RECLAIM usage from kasan/kmsan
has been added to the -mm mm-unstable branch. Its filename is
kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Subject: kasan,kmsan: remove __GFP_KSWAPD_RECLAIM usage from kasan/kmsan
Date: Sun, 28 May 2023 00:25:31 +0900
syzbot is reporting lockdep warning in __stack_depot_save(), for
the caller of __stack_depot_save() (i.e. __kasan_record_aux_stack() in
this report) is responsible for masking __GFP_KSWAPD_RECLAIM flag in
order not to wake kswapd which in turn wakes kcompactd.
Since kasan/kmsan functions might be called with arbitrary locks held,
mask __GFP_KSWAPD_RECLAIM flag from all GFP_NOWAIT/GFP_ATOMIC allocations
in kasan/kmsan.
Note that kmsan_save_stack_with_flags() is changed to mask both
__GFP_DIRECT_RECLAIM flag and __GFP_KSWAPD_RECLAIM flag, for
wakeup_kswapd() from wake_all_kswapds() from __alloc_pages_slowpath()
calls wakeup_kcompactd() if __GFP_KSWAPD_RECLAIM flag is set and
__GFP_DIRECT_RECLAIM flag is not set.
Link: https://lkml.kernel.org/r/656cb4f5-998b-c8d7-3c61-c2d37aa90f9a@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Reported-by: syzbot <syzbot+ece2915262061d6e0ac1@xxxxxxxxxxxxxxxxxxxxxxxxx>
Closes: https://syzkaller.appspot.com/bug?extid=ece2915262061d6e0ac1
Reviewed-by: "Huang, Ying" <ying.huang@xxxxxxxxx>
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Marco Elver <elver@xxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/kasan/generic.c | 4 ++--
mm/kasan/tags.c | 2 +-
mm/kmsan/core.c | 6 +++---
mm/kmsan/instrumentation.c | 2 +-
4 files changed, 7 insertions(+), 7 deletions(-)
--- a/mm/kasan/generic.c~kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan
+++ a/mm/kasan/generic.c
@@ -488,7 +488,7 @@ static void __kasan_record_aux_stack(voi
return;
alloc_meta->aux_stack[1] = alloc_meta->aux_stack[0];
- alloc_meta->aux_stack[0] = kasan_save_stack(GFP_NOWAIT, can_alloc);
+ alloc_meta->aux_stack[0] = kasan_save_stack(0, can_alloc);
}
void kasan_record_aux_stack(void *addr)
@@ -518,7 +518,7 @@ void kasan_save_free_info(struct kmem_ca
if (!free_meta)
return;
- kasan_set_track(&free_meta->free_track, GFP_NOWAIT);
+ kasan_set_track(&free_meta->free_track, 0);
/* The object was freed and has free track set. */
*(u8 *)kasan_mem_to_shadow(object) = KASAN_SLAB_FREETRACK;
}
--- a/mm/kasan/tags.c~kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan
+++ a/mm/kasan/tags.c
@@ -140,5 +140,5 @@ void kasan_save_alloc_info(struct kmem_c
void kasan_save_free_info(struct kmem_cache *cache, void *object)
{
- save_stack_info(cache, object, GFP_NOWAIT, true);
+ save_stack_info(cache, object, 0, true);
}
--- a/mm/kmsan/core.c~kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan
+++ a/mm/kmsan/core.c
@@ -74,7 +74,7 @@ depot_stack_handle_t kmsan_save_stack_wi
nr_entries = stack_trace_save(entries, KMSAN_STACK_DEPTH, 0);
/* Don't sleep. */
- flags &= ~__GFP_DIRECT_RECLAIM;
+ flags &= ~(__GFP_DIRECT_RECLAIM | __GFP_KSWAPD_RECLAIM);
handle = __stack_depot_save(entries, nr_entries, flags, true);
return stack_depot_set_extra_bits(handle, extra);
@@ -245,7 +245,7 @@ depot_stack_handle_t kmsan_internal_chai
extra_bits = kmsan_extra_bits(depth, uaf);
entries[0] = KMSAN_CHAIN_MAGIC_ORIGIN;
- entries[1] = kmsan_save_stack_with_flags(GFP_ATOMIC, 0);
+ entries[1] = kmsan_save_stack_with_flags(__GFP_HIGH, 0);
entries[2] = id;
/*
* @entries is a local var in non-instrumented code, so KMSAN does not
@@ -253,7 +253,7 @@ depot_stack_handle_t kmsan_internal_chai
* positives when __stack_depot_save() passes it to instrumented code.
*/
kmsan_internal_unpoison_memory(entries, sizeof(entries), false);
- handle = __stack_depot_save(entries, ARRAY_SIZE(entries), GFP_ATOMIC,
+ handle = __stack_depot_save(entries, ARRAY_SIZE(entries), __GFP_HIGH,
true);
return stack_depot_set_extra_bits(handle, extra_bits);
}
--- a/mm/kmsan/instrumentation.c~kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan
+++ a/mm/kmsan/instrumentation.c
@@ -282,7 +282,7 @@ void __msan_poison_alloca(void *address,
/* stack_depot_save() may allocate memory. */
kmsan_enter_runtime();
- handle = stack_depot_save(entries, ARRAY_SIZE(entries), GFP_ATOMIC);
+ handle = stack_depot_save(entries, ARRAY_SIZE(entries), __GFP_HIGH);
kmsan_leave_runtime();
kmsan_internal_set_shadow_origin(address, size, -1, handle,
_
Patches currently in -mm which might be from penguin-kernel@xxxxxxxxxxxxxxxxxxx are
workingset-refactor-lru-refault-to-expose-refault-recency-check-fix.patch
mm-page_alloc-dont-wake-up-kswapd-from-rmqueue-unless-__gfp_kswapd_reclaim-is-specified.patch
kasankmsan-remove-__gfp_kswapd_reclaim-usage-from-kasan-kmsan.patch
debugobjects-turn-off-debug_objects_enabled-from-debug_objects_oom.patch
