summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorQian Cai <cai@lca.pw>2020-03-21 18:22:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-03-21 18:56:06 -0700
commitd72520ad004a8ce18a6ba6cde317f0081b27365a (patch)
treed84f7e84297576d06669dbcf80df1ab88de4011f
parentd41e2f3bd54699f85b3d6f45abd09fa24a222cb9 (diff)
page-flags: fix a crash at SetPageError(THP_SWAP)
Commit bd4c82c22c36 ("mm, THP, swap: delay splitting THP after swapped out") supported writing THP to a swap device but forgot to upgrade an older commit df8c94d13c7e ("page-flags: define behavior of FS/IO-related flags on compound pages") which could trigger a crash during THP swapping out with DEBUG_VM_PGFLAGS=y, kernel BUG at include/linux/page-flags.h:317! page dumped because: VM_BUG_ON_PAGE(1 && PageCompound(page)) page:fffff3b2ec3a8000 refcount:512 mapcount:0 mapping:000000009eb0338c index:0x7f6e58200 head:fffff3b2ec3a8000 order:9 compound_mapcount:0 compound_pincount:0 anon flags: 0x45fffe0000d8454(uptodate|lru|workingset|owner_priv_1|writeback|head|reclaim|swapbacked) end_swap_bio_write() SetPageError(page) VM_BUG_ON_PAGE(1 && PageCompound(page)) <IRQ> bio_endio+0x297/0x560 dec_pending+0x218/0x430 [dm_mod] clone_endio+0xe4/0x2c0 [dm_mod] bio_endio+0x297/0x560 blk_update_request+0x201/0x920 scsi_end_request+0x6b/0x4b0 scsi_io_completion+0x509/0x7e0 scsi_finish_command+0x1ed/0x2a0 scsi_softirq_done+0x1c9/0x1d0 __blk_mqnterrupt+0xf/0x20 </IRQ> Fix by checking PF_NO_TAIL in those places instead. Fixes: bd4c82c22c36 ("mm, THP, swap: delay splitting THP after swapped out") Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: "Huang, Ying" <ying.huang@intel.com> Acked-by: Rafael Aquini <aquini@redhat.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200310235846.1319-1-cai@lca.pw Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--include/linux/page-flags.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 1bf83c8fcaa7..77de28bfefb0 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -311,7 +311,7 @@ static inline int TestClearPage##uname(struct page *page) { return 0; }
__PAGEFLAG(Locked, locked, PF_NO_TAIL)
PAGEFLAG(Waiters, waiters, PF_ONLY_HEAD) __CLEARPAGEFLAG(Waiters, waiters, PF_ONLY_HEAD)
-PAGEFLAG(Error, error, PF_NO_COMPOUND) TESTCLEARFLAG(Error, error, PF_NO_COMPOUND)
+PAGEFLAG(Error, error, PF_NO_TAIL) TESTCLEARFLAG(Error, error, PF_NO_TAIL)
PAGEFLAG(Referenced, referenced, PF_HEAD)
TESTCLEARFLAG(Referenced, referenced, PF_HEAD)
__SETPAGEFLAG(Referenced, referenced, PF_HEAD)