KCSAN: data-race in ext4_mark_iloc_dirty / find_inode_bit (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 17e7124a Merge tag '5.12-rc6-smb3' of git://git.samba.org/..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1224508ed00000
kernel config: https://syzkaller.appspot.com/x/.config?x=766d02fe10aa7ea6
dashboard link: https://syzkaller.appspot.com/bug?extid=5d1d576eaf2246b8a84c
compiler: Debian clang version 11.0.1-2
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

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+5d1d57...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in ext4_mark_iloc_dirty / find_inode_bit

write to 0xffff88811acc7a14 of 4 bytes by task 32178 on cpu 0:
ext4_do_update_inode fs/ext4/inode.c:5081 [inline]
ext4_mark_iloc_dirty+0x82f/0x1700 fs/ext4/inode.c:5726
__ext4_mark_inode_dirty+0x4db/0x5e0 fs/ext4/inode.c:5920
ext4_ext_tree_init+0x7e/0x90 fs/ext4/extents.c:828
__ext4_new_inode+0x29ff/0x2fe0 fs/ext4/ialloc.c:1327
ext4_symlink+0x2d1/0x780 fs/ext4/namei.c:3347
vfs_symlink+0xbe/0x170 fs/namei.c:4178
do_symlinkat+0x11e/0x2b0 fs/namei.c:4208
__do_sys_symlink fs/namei.c:4229 [inline]
__se_sys_symlink fs/namei.c:4227 [inline]
__x64_sys_symlink+0x32/0x40 fs/namei.c:4227
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88811acc7a14 of 4 bytes by task 32180 on cpu 1:
recently_deleted fs/ext4/ialloc.c:702 [inline]
find_inode_bit+0x227/0x3a0 fs/ext4/ialloc.c:728
__ext4_new_inode+0xb6c/0x2fe0 fs/ext4/ialloc.c:1063
ext4_symlink+0x2d1/0x780 fs/ext4/namei.c:3347
vfs_symlink+0xbe/0x170 fs/namei.c:4178
do_symlinkat+0x11e/0x2b0 fs/namei.c:4208
__do_sys_symlink fs/namei.c:4229 [inline]
__se_sys_symlink fs/namei.c:4227 [inline]
__x64_sys_symlink+0x32/0x40 fs/namei.c:4227
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 32180 Comm: syz-executor.4 Tainted: G W 5.12.0-rc6-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.