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BUG: KCSAN: data-race in mem_cgroup_track_foreign_dirty_slowpath / mem_cgroup_track_foreign_dirty_slowpath

write to 0xffff8881079905d8 of 8 bytes by task 4093 on cpu 0:
 mem_cgroup_track_foreign_dirty_slowpath+0x3b3/0x440
 mem_cgroup_track_foreign_dirty include/linux/memcontrol.h:1579 [inline]
 folio_account_dirtied mm/page-writeback.c:2771 [inline]
 __folio_mark_dirty+0x3f5/0x4e0 mm/page-writeback.c:2812
 mark_buffer_dirty+0x134/0x230 fs/buffer.c:1196
 __block_write_begin_int+0x84d/0xfa0 fs/buffer.c:2127
 block_page_mkwrite+0x1bd/0x3f0 fs/buffer.c:2629
 ext4_page_mkwrite+0x73d/0xb70 fs/ext4/inode.c:6180
 do_page_mkwrite mm/memory.c:3176 [inline]
 do_shared_fault mm/memory.c:5398 [inline]
 do_fault mm/memory.c:5460 [inline]
 do_pte_missing mm/memory.c:3979 [inline]
 handle_pte_fault mm/memory.c:5801 [inline]
 __handle_mm_fault mm/memory.c:5944 [inline]
 handle_mm_fault+0x12f7/0x2ac0 mm/memory.c:6112
 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

read to 0xffff8881079905d8 of 8 bytes by task 4094 on cpu 1:
 mem_cgroup_track_foreign_dirty_slowpath+0xdb/0x440 mm/memcontrol.c:3271
 mem_cgroup_track_foreign_dirty include/linux/memcontrol.h:1579 [inline]
 folio_account_dirtied mm/page-writeback.c:2771 [inline]
 __folio_mark_dirty+0x3f5/0x4e0 mm/page-writeback.c:2812
 mark_buffer_dirty+0x134/0x230 fs/buffer.c:1196
 __block_commit_write fs/buffer.c:2189 [inline]
 block_write_end+0x123/0x210 fs/buffer.c:2265
 generic_write_end+0x5c/0x160 fs/buffer.c:2279
 fat_write_end+0x4e/0x160 fs/fat/inode.c:242
 generic_perform_write+0x33c/0x4a0 mm/filemap.c:4061
 __generic_file_write_iter+0xa1/0x120 mm/filemap.c:4147
 generic_file_write_iter+0x77/0x1c0 mm/filemap.c:4173
 iter_file_splice_write+0x5f1/0x980 fs/splice.c:743
 do_splice_from fs/splice.c:941 [inline]
 direct_splice_actor+0x160/0x2c0 fs/splice.c:1164
 splice_direct_to_actor+0x302/0x670 fs/splice.c:1108
 do_splice_direct_actor fs/splice.c:1207 [inline]
 do_splice_direct+0xd7/0x150 fs/splice.c:1233
 do_sendfile+0x398/0x660 fs/read_write.c:1363
 __do_sys_sendfile64 fs/read_write.c:1424 [inline]
 __se_sys_sendfile64 fs/read_write.c:1410 [inline]
 __x64_sys_sendfile64+0x110/0x150 fs/read_write.c:1410
 x64_sys_call+0xfbd/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:41
 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: 0x00000000ffff9a8e -> 0x00000000ffff9af9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 4094 Comm: syz.4.192 Not tainted 6.13.0-rc6-syzkaller-00038-g09a0fa92e5b4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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