syzbot

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BUG: KCSAN: data-race in __mark_inode_dirty / __writeback_single_inode

read-write to 0xffff8881005c7ca0 of 8 bytes by task 12432 on cpu 0:
 __writeback_single_inode+0x201/0x870 fs/fs-writeback.c:1687
 writeback_sb_inodes+0x559/0xb20 fs/fs-writeback.c:1947
 __writeback_inodes_wb+0x9a/0x1a0 fs/fs-writeback.c:2018
 wb_writeback+0x270/0x720 fs/fs-writeback.c:2129
 wb_check_start_all fs/fs-writeback.c:2255 [inline]
 wb_do_writeback fs/fs-writeback.c:2281 [inline]
 wb_workfn+0x4ea/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+0x526/0x700 kernel/workqueue.c:3390
 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 0xffff8881005c7ca0 of 8 bytes by task 13046 on cpu 1:
 __mark_inode_dirty+0x19f/0x7e0 fs/fs-writeback.c:2508
 generic_update_time fs/inode.c:1969 [inline]
 inode_update_time fs/inode.c:1982 [inline]
 __file_update_time fs/inode.c:2171 [inline]
 file_update_time+0x295/0x2c0 fs/inode.c:2201
 ext4_page_mkwrite+0x1a4/0xb70 fs/ext4/inode.c:6132
 do_page_mkwrite mm/memory.c:3142 [inline]
 wp_page_shared mm/memory.c:3545 [inline]
 do_wp_page+0xc69/0x22c0 mm/memory.c:3695
 handle_pte_fault mm/memory.c:5538 [inline]
 __handle_mm_fault mm/memory.c:5665 [inline]
 handle_mm_fault+0xbf0/0x2940 mm/memory.c:5833
 do_user_addr_fault arch/x86/mm/fault.c:1338 [inline]
 handle_page_fault arch/x86/mm/fault.c:1481 [inline]
 exc_page_fault+0x3b9/0x650 arch/x86/mm/fault.c:1539
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623

value changed: 0x0000000000020085 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 13046 Comm: syz.1.2220 Not tainted 6.11.0-rc2-syzkaller-00194-gafdab700f65e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
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