KCSAN: data-race in __add_to_page_cache_locked / invalidate_inode_pages2_range (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 84b13499 Merge tag 'for-linus' of git://git.kernel.org/pub..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13134721900000
kernel config: https://syzkaller.appspot.com/x/.config?x=a5d60aa8b6ca55a0
dashboard link: https://syzkaller.appspot.com/bug?extid=09166b76b415b8869254
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+09166b...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __add_to_page_cache_locked / invalidate_inode_pages2_range

write to 0xffff8880bb7048b0 of 8 bytes by task 22992 on cpu 0:
__add_to_page_cache_locked+0x2cc/0x710 mm/filemap.c:868
add_to_page_cache_lru+0xa0/0x1b0 mm/filemap.c:919
page_cache_readahead_unbounded+0x234/0x470 mm/readahead.c:228
ondemand_readahead+0x4e4/0x6e0 mm/readahead.c:273
page_cache_sync_readahead+0x178/0x1a0 mm/readahead.c:585
generic_file_buffered_read+0x2ec/0x1f60 mm/filemap.c:2101
generic_file_read_iter+0x7d/0x3e0 mm/filemap.c:2405
call_read_iter include/linux/fs.h:1876 [inline]
generic_file_splice_read+0x22b/0x310 fs/splice.c:312
do_splice_to fs/splice.c:870 [inline]
splice_direct_to_actor+0x2a8/0x660 fs/splice.c:950
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 0xffff8880bb7048b0 of 8 bytes by task 23010 on cpu 1:
invalidate_inode_pages2_range+0x40/0x780 mm/truncate.c:695
generic_file_direct_write+0x15c/0x3e0 mm/filemap.c:3290
__generic_file_write_iter+0x19c/0x330 mm/filemap.c:3489
generic_file_write_iter+0x2f3/0x3e0 mm/filemap.c:3564
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

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23010 Comm: syz-executor.3 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.