syzbot

EXT4-fs (loop5): mount failed
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BUG: KCSAN: data-race in has_bh_in_lru / invalidate_bh_lru

write to 0xffff888237c277a0 of 8 bytes by task 10158 on cpu 0:
 __invalidate_bh_lrus fs/buffer.c:1426 [inline]
 invalidate_bh_lru+0x89/0xe0 fs/buffer.c:1438
 csd_do_func kernel/smp.c:136 [inline]
 smp_call_function_many_cond+0x719/0xb70 kernel/smp.c:883
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1057
 on_each_cpu_cond include/linux/smp.h:106 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1457
 kill_bdev block/bdev.c:90 [inline]
 set_blocksize+0x1e3/0x270 block/bdev.c:207
 sb_set_blocksize+0x93/0x170 block/bdev.c:240
 ext4_load_super fs/ext4/super.c:5199 [inline]
 __ext4_fill_super fs/ext4/super.c:5354 [inline]
 ext4_fill_super+0x1480/0x37c0 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1694
 get_tree_bdev+0x1f/0x30 fs/super.c:1717
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5856
 vfs_get_tree+0x57/0x1d0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x288/0x8d0 fs/namespace.c:3834
 path_mount+0x4d0/0xbc0 fs/namespace.c:4154
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4360
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4360
 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888237c277a0 of 8 bytes by task 10139 on cpu 1:
 has_bh_in_lru+0x35/0x1f0 fs/buffer.c:1448
 smp_call_function_many_cond+0x2a7/0xb70 kernel/smp.c:836
 on_each_cpu_cond_mask+0x3c/0x80 kernel/smp.c:1057
 on_each_cpu_cond include/linux/smp.h:106 [inline]
 invalidate_bh_lrus+0x2a/0x30 fs/buffer.c:1457
 invalidate_bdev+0x42/0x70 block/bdev.c:100
 __ext4_fill_super fs/ext4/super.c:5799 [inline]
 ext4_fill_super+0x2cf6/0x37c0 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1694
 get_tree_bdev+0x1f/0x30 fs/super.c:1717
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5856
 vfs_get_tree+0x57/0x1d0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x288/0x8d0 fs/namespace.c:3834
 path_mount+0x4d0/0xbc0 fs/namespace.c:4154
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4360
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4360
 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff88811b060c30 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10139 Comm: syz.5.1874 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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