EXT4-fs warning (device loop1): read_mmp_block:111: Error -117 while reading MMP block 0
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BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237c27550 of 8 bytes by task 10649 on cpu 0:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x498/0x8e0 fs/buffer.c:1410
 bdev_getblk+0x4d/0x3f0 include/linux/gfp.h:-1
 __bread_gfp+0x51/0x240 fs/buffer.c:1515
 sb_bread include/linux/buffer_head.h:346 [inline]
 fat_ent_bread+0xc9/0x1a0 fs/fat/fatent.c:109
 fat_ent_read+0x3b3/0x5c0 fs/fat/fatent.c:368
 fat_get_cluster+0x4de/0x820 fs/fat/cache.c:261
 fat_free fs/fat/file.c:346 [inline]
 fat_truncate_blocks+0x26f/0x5a0 fs/fat/file.c:394
 fat_write_failed fs/fat/inode.c:219 [inline]
 fat_write_begin+0xbd/0xe0 fs/fat/inode.c:234
 generic_cont_expand_simple+0xb0/0x150 fs/buffer.c:2485
 fat_cont_expand+0x3e/0x170 fs/fat/file.c:223
 fat_fallocate+0x177/0x1c0 fs/fat/file.c:301
 vfs_fallocate+0x3b6/0x450 fs/open.c:339
 ksys_fallocate fs/open.c:363 [inline]
 __do_sys_fallocate fs/open.c:368 [inline]
 __se_sys_fallocate fs/open.c:366 [inline]
 __x64_sys_fallocate+0x7a/0xd0 fs/open.c:366
 x64_sys_call+0x1cd4/0x3000 arch/x86/include/generated/asm/syscalls_64.h:286
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c27550 of 8 bytes by task 10663 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 cpu_needs_drain mm/swap.c:787 [inline]
 __lru_add_drain_all+0x287/0x450 mm/swap.c:877
 lru_add_drain_all+0x10/0x20 mm/swap.c:893
 invalidate_bdev+0x47/0x70 block/bdev.c:101
 __ext4_fill_super fs/ext4/super.c:5752 [inline]
 ext4_fill_super+0x2d52/0x3800 fs/ext4/super.c:5777
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1691
 get_tree_bdev+0x1f/0x30 fs/super.c:1714
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5809
 vfs_get_tree+0x57/0x1d0 fs/super.c:1751
 fc_mount fs/namespace.c:1199 [inline]
 do_new_mount_fc fs/namespace.c:3636 [inline]
 do_new_mount+0x288/0x700 fs/namespace.c:3712
 path_mount+0x4d0/0xbc0 fs/namespace.c:4022
 do_mount fs/namespace.c:4035 [inline]
 __do_sys_mount fs/namespace.c:4224 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4201
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4201
 x64_sys_call+0x2cca/0x3000 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc0/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0xffff88811a094a90

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10663 Comm: syz.1.2197 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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