[moderation] [ext4?] KCSAN: data-race in perf_trace_writeback_dirty_inode_template / writeback_sb_inodes

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 55027e689933 Merge tag 'input-for-v6.10-rc5' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=146dc961980000
kernel config: https://syzkaller.appspot.com/x/.config?x=7e87b541dc1fc960
dashboard link: https://syzkaller.appspot.com/bug?extid=038f522c05b2ff4cf692
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
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.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/12deab70203e/disk-55027e68.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/29d492adc137/vmlinux-55027e68.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f5d493b5e976/bzImage-55027e68.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+038f52...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in perf_trace_writeback_dirty_inode_template / writeback_sb_inodes

write to 0xffff888106e933f0 of 8 bytes by task 36 on cpu 1:
writeback_sb_inodes+0x31b/0xb20 fs/fs-writeback.c:1936
wb_writeback+0x25e/0x720 fs/fs-writeback.c:2127
wb_do_writeback fs/fs-writeback.c:2274 [inline]
wb_workfn+0x1a8/0x940 fs/fs-writeback.c:2314
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
worker_thread+0x526/0x730 kernel/workqueue.c:3393
kthread+0x1d1/0x210 kernel/kthread.c:389
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888106e933f0 of 8 bytes by task 6804 on cpu 0:
perf_trace_writeback_dirty_inode_template+0x1aa/0x240 include/trace/events/writeback.h:96
trace_writeback_dirty_inode include/trace/events/writeback.h:141 [inline]
__mark_inode_dirty+0x605/0x7e0 fs/fs-writeback.c:2488
mark_inode_dirty include/linux/fs.h:2404 [inline]
dquot_alloc_space include/linux/quotaops.h:319 [inline]
dquot_alloc_block include/linux/quotaops.h:336 [inline]
ext4_mb_new_blocks+0x103e/0x2020 fs/ext4/mballoc.c:6185
ext4_ext_map_blocks+0x10a1/0x33b0 fs/ext4/extents.c:4318
ext4_map_blocks+0x72a/0xf50 fs/ext4/inode.c:623
ext4_alloc_file_blocks+0x285/0x700 fs/ext4/extents.c:4495
ext4_fallocate+0x782/0x1190 fs/ext4/extents.c:4792
vfs_fallocate+0x380/0x3e0 fs/open.c:330
do_vfs_ioctl+0x1481/0x1560 fs/ioctl.c:886
__do_sys_ioctl fs/ioctl.c:905 [inline]
__se_sys_ioctl+0x81/0x150 fs/ioctl.c:893
__x64_sys_ioctl+0x43/0x50 fs/ioctl.c:893
x64_sys_call+0x1581/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000020001 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 6804 Comm: syz.4.923 Not tainted 6.10.0-rc5-syzkaller-00018-g55027e689933 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================


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