KCSAN: data-race in __delete_from_page_cache / file_write_and_wait_range (2)

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syzbot

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Sep 21, 2020, 6:02:23 AM9/21/20
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Hello,

syzbot found the following issue on:

HEAD commit: bdcf11de Merge tag 'riscv-for-linus-5.9-rc6' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13fed23d900000
kernel config: https://syzkaller.appspot.com/x/.config?x=71d95d75ec48fd6f
dashboard link: https://syzkaller.appspot.com/bug?extid=798ec11280d97ae7b4c0
compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project.git ca2dcbd030eadbf0aa9b660efe864ff08af6e18b)
CC: [ak...@linux-foundation.org linux-...@vger.kernel.org linu...@kvack.org]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+798ec1...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __delete_from_page_cache / file_write_and_wait_range

write to 0xffff88821abb0c90 of 8 bytes by task 4383 on cpu 0:
page_cache_delete mm/filemap.c:154 [inline]
__delete_from_page_cache+0x282/0x380 mm/filemap.c:239
invalidate_complete_page2+0x126/0x2c0 mm/truncate.c:651
invalidate_inode_pages2_range+0x465/0x780 mm/truncate.c:744
iomap_dio_rw+0x503/0x980 fs/iomap/direct-io.c:488
ext4_dio_write_iter fs/ext4/file.c:548 [inline]
ext4_file_write_iter+0xdd5/0x1060 fs/ext4/file.c:658
call_write_iter include/linux/fs.h:1882 [inline]
do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713
do_iter_write+0x112/0x4b0 fs/read_write.c:1018
vfs_iter_write+0x4c/0x70 fs/read_write.c:1059
iter_file_splice_write+0x41a/0x770 fs/splice.c:750
do_splice_from fs/splice.c:846 [inline]
direct_splice_actor+0x95/0x160 fs/splice.c:1016
splice_direct_to_actor+0x365/0x660 fs/splice.c:971
do_splice_direct+0xf2/0x170 fs/splice.c:1059
do_sendfile+0x56a/0xba0 fs/read_write.c:1540
__do_sys_sendfile64 fs/read_write.c:1601 [inline]
__se_sys_sendfile64 fs/read_write.c:1587 [inline]
__x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1587
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88821abb0c90 of 8 bytes by task 4386 on cpu 1:
mapping_needs_writeback mm/filemap.c:630 [inline]
file_write_and_wait_range+0x79/0x120 mm/filemap.c:760
ext4_sync_file+0xfc/0x6e0 fs/ext4/fsync.c:151
vfs_fsync_range+0x107/0x120 fs/sync.c:200
generic_write_sync include/linux/fs.h:2747 [inline]
ext4_buffered_write_iter+0x369/0x3b0 fs/ext4/file.c:276
ext4_file_write_iter+0x768/0x1060 include/linux/fs.h:784
call_write_iter include/linux/fs.h:1882 [inline]
do_iter_readv_writev+0x32e/0x3d0 fs/read_write.c:713
do_iter_write+0x112/0x4b0 fs/read_write.c:1018
vfs_iter_write+0x4c/0x70 fs/read_write.c:1059
iter_file_splice_write+0x41a/0x770 fs/splice.c:750
do_splice_from fs/splice.c:846 [inline]
direct_splice_actor+0x95/0x160 fs/splice.c:1016
splice_direct_to_actor+0x365/0x660 fs/splice.c:971
do_splice_direct+0xf2/0x170 fs/splice.c:1059
do_sendfile+0x56a/0xba0 fs/read_write.c:1540
__do_sys_sendfile64 fs/read_write.c:1595 [inline]
__se_sys_sendfile64 fs/read_write.c:1587 [inline]
__x64_sys_sendfile64+0xa9/0x130 fs/read_write.c:1587
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 4386 Comm: syz-executor.0 Not tainted 5.9.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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syzbot

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Jun 24, 2021, 9:53:14 PM6/24/21
to syzkaller-upst...@googlegroups.com
Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.
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