The patch titled
Subject: mm: fix trying to reclaim unevictable lru page when calling madvise_pageout
has been added to the -mm tree. Its filename is
mm-fix-trying-to-reclaim-unevictable-lru-page-when-calling-madvise_pageout.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-fix-trying-to-reclaim-unevictable-lru-page-when-calling-madvise_pageout.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-fix-trying-to-reclaim-unevictable-lru-page-when-calling-madvise_pageout.patch
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------------------------------------------------------
From: zhong jiang <zhongjiang@xxxxxxxxxx>
Subject: mm: fix trying to reclaim unevictable lru page when calling madvise_pageout
Recently, I hit the following issue when running upstream.
kernel BUG at mm/vmscan.c:1521!
invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 0 PID: 23385 Comm: syz-executor.6 Not tainted 5.4.0-rc4+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:shrink_page_list+0x12b6/0x3530 mm/vmscan.c:1521
Code: de f5 ff ff e8 ab 79 eb ff 4c 89 f7 e8 43 33 0d 00 e9 cc f5 ff ff e8 99 79 eb ff 48 c7 c6 a0 34 2b a0 4c 89 f7 e8 1a 4d 05 00 <0f> 0b e8 83 79 eb ff 48 89 d8 48 c1 e8 03 42 80 3c 38 00 0f 85 74
RSP: 0018:ffff88819a3df5a0 EFLAGS: 00010286
RAX: 0000000000040000 RBX: ffffea00061c3980 RCX: ffffffff814fba36
RDX: 00000000000056f7 RSI: ffffc9000c02c000 RDI: ffff8881f70268cc
RBP: ffff88819a3df898 R08: ffffed103ee05de0 R09: ffffed103ee05de0
R10: 0000000000000001 R11: ffffed103ee05ddf R12: ffff88819a3df6f0
R13: ffff88819a3df6f0 R14: ffffea00061c3980 R15: dffffc0000000000
FS: 00007f21b9d8e700(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d621000 CR3: 00000001c8c46004 CR4: 00000000007606f0
DR0: 0000000020000140 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
PKRU: 55555554
Call Trace:
reclaim_pages+0x499/0x800 mm/vmscan.c:2188
madvise_cold_or_pageout_pte_range+0x58a/0x710 mm/madvise.c:453
walk_pmd_range mm/pagewalk.c:53 [inline]
walk_pud_range mm/pagewalk.c:112 [inline]
walk_p4d_range mm/pagewalk.c:139 [inline]
walk_pgd_range mm/pagewalk.c:166 [inline]
__walk_page_range+0x45a/0xc20 mm/pagewalk.c:261
walk_page_range+0x179/0x310 mm/pagewalk.c:349
madvise_pageout_page_range mm/madvise.c:506 [inline]
madvise_pageout+0x1f0/0x330 mm/madvise.c:542
madvise_vma mm/madvise.c:931 [inline]
__do_sys_madvise+0x7d2/0x1600 mm/madvise.c:1113
do_syscall_64+0x9f/0x4c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
madvise_pageout() accesses the specified range of the vma and isolates
them, then runs shrink_page_list() to reclaim its memory. But it also
isolates the unevictable pages to reclaim. Hence, we can catch the cases
in shrink_page_list().
The root cause is that we scan the page tables instead of specific LRU
list. and so we need to filter out the unevictable lru pages from our
end.
Link: http://lkml.kernel.org/r/1572616245-18946-1-git-send-email-zhongjiang@xxxxxxxxxx
Fixes: 1a4e58cce84e ("mm: introduce MADV_PAGEOUT")
Signed-off-by: zhong jiang <zhongjiang@xxxxxxxxxx>
Suggested-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Acked-by: Minchan Kim <minchan@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/madvise.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
--- a/mm/madvise.c~mm-fix-trying-to-reclaim-unevictable-lru-page-when-calling-madvise_pageout
+++ a/mm/madvise.c
@@ -363,8 +363,12 @@ static int madvise_cold_or_pageout_pte_r
ClearPageReferenced(page);
test_and_clear_page_young(page);
if (pageout) {
- if (!isolate_lru_page(page))
- list_add(&page->lru, &page_list);
+ if (!isolate_lru_page(page)) {
+ if (PageUnevictable(page))
+ putback_lru_page(page);
+ else
+ list_add(&page->lru, &page_list);
+ }
} else
deactivate_page(page);
huge_unlock:
@@ -441,8 +445,12 @@ regular_page:
ClearPageReferenced(page);
test_and_clear_page_young(page);
if (pageout) {
- if (!isolate_lru_page(page))
- list_add(&page->lru, &page_list);
+ if (!isolate_lru_page(page)) {
+ if (PageUnevictable(page))
+ putback_lru_page(page);
+ else
+ list_add(&page->lru, &page_list);
+ }
} else
deactivate_page(page);
}
_
Patches currently in -mm which might be from zhongjiang@xxxxxxxxxx are
mm-fix-trying-to-reclaim-unevictable-lru-page-when-calling-madvise_pageout.patch
mm-gup-allow-cma-migration-to-propagate-errors-back-to-caller.patch
mm-split_huge_pages_fops-should-be-defined-with-define_debugfs_attribute.patch
mm-cma_debug-use-define_debugfs_attribute-to-define-debugfs-fops.patch
mm-hwpoison-inject-use-define_debugfs_attribute-to-define-debugfs-fops.patch
