loop5: detected capacity change from 0 to 512
EXT4-fs: Ignoring removed bh option
==================================================================
BUG: KCSAN: data-race in find_get_block_common / has_bh_in_lru

read-write to 0xffff888237c26f50 of 8 bytes by task 20699 on cpu 0:
 bh_lru_install fs/buffer.c:1345 [inline]
 find_get_block_common+0x4f0/0x960 fs/buffer.c:1410
 __find_get_block_nonatomic fs/buffer.c:1429 [inline]
 bdev_getblk+0x83/0x3b0 fs/buffer.c:1453
 __bread_gfp+0x51/0x250 fs/buffer.c:1515
 sb_bread include/linux/buffer_head.h:346 [inline]
 fat__get_entry fs/fat/dir.c:100 [inline]
 fat_get_entry+0x46e/0x5d0 fs/fat/dir.c:128
 fat_get_short_entry fs/fat/dir.c:885 [inline]
 fat_subdirs+0xf6/0x190 fs/fat/dir.c:951
 fat_read_root+0x316/0x360 fs/fat/inode.c:1347
 fat_fill_super+0x15bf/0x1ce0 fs/fat/inode.c:1816
 vfat_fill_super+0x24/0x30 fs/fat/namei_vfat.c:1197
 get_tree_bdev_flags+0x28e/0x300 fs/super.c:1692
 get_tree_bdev+0x1f/0x30 fs/super.c:1715
 vfat_get_tree+0x1c/0x30 fs/fat/namei_vfat.c:1202
 vfs_get_tree+0x57/0x1d0 fs/super.c:1815
 do_new_mount+0x207/0x5e0 fs/namespace.c:3805
 path_mount+0x4a4/0xb20 fs/namespace.c:4120
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4321
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4321
 x64_sys_call+0x2b4d/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c26f50 of 8 bytes by task 20695 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1551
 smp_call_function_many_cond+0x2a9/0xc60 kernel/smp.c:821
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1044
 on_each_cpu_cond include/linux/smp.h:105 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1560
 kill_bdev block/bdev.c:90 [inline]
 set_blocksize+0x24f/0x310 block/bdev.c:207
 sb_set_blocksize+0x7a/0x100 block/bdev.c:224
 ext4_load_super fs/ext4/super.c:5110 [inline]
 __ext4_fill_super fs/ext4/super.c:5262 [inline]
 ext4_fill_super+0x12ab/0x34e0 fs/ext4/super.c:5724
 get_tree_bdev_flags+0x28e/0x300 fs/super.c:1692
 get_tree_bdev+0x1f/0x30 fs/super.c:1715
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5756
 vfs_get_tree+0x57/0x1d0 fs/super.c:1815
 do_new_mount+0x207/0x5e0 fs/namespace.c:3805
 path_mount+0x4a4/0xb20 fs/namespace.c:4120
 do_mount fs/namespace.c:4133 [inline]
 __do_sys_mount fs/namespace.c:4344 [inline]
 __se_sys_mount+0x28f/0x2e0 fs/namespace.c:4321
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4321
 x64_sys_call+0x2b4d/0x2ff0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888118d75478 -> 0xffff888118e5f750

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 20695 Comm: syz.5.6277 Not tainted 6.16.0-syzkaller-10355-gf2d282e1dfb3 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
==================================================================
EXT4-fs (loop5): feature flags set on rev 0 fs, running e2fsck is recommended
EXT4-fs (loop5): mounting ext2 file system using the ext4 subsystem
EXT4-fs (loop5): warning: mounting unchecked fs, running e2fsck is recommended
[EXT4 FS bs=2048, gc=1, bpg=16384, ipg=32, mo=c002e01c, mo2=0006]
EXT4-fs (loop5): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.