EXT4-fs error (device loop1): ext4_mb_generate_buddy:1220: group 0, 
==================================================================
BUG: KCSAN: data-race in data_alloc / data_push_tail

write to 0xffffffff88b73c10 of 8 bytes by task 29 on cpu 0:
 data_alloc+0x216/0x2c0 kernel/printk/printk_ringbuffer.c:1082
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2269
 vprintk_emit+0x13a/0x610 kernel/printk/printk.c:2329
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2363
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2373
 kauditd_printk_skb kernel/audit.c:546 [inline]
 kauditd_hold_skb+0x1a3/0x1b0 kernel/audit.c:581
 kauditd_send_queue+0x288/0x2e0 kernel/audit.c:766
 kauditd_thread+0x42a/0x650 kernel/audit.c:890
 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 0xffffffff88b73c10 of 8 bytes by task 17134 on cpu 1:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679
 data_realloc kernel/printk/printk_ringbuffer.c:1143 [inline]
 prb_reserve_in_last+0x773/0xc10 kernel/printk/printk_ringbuffer.c:1440
 vprintk_store+0x45b/0x810 kernel/printk/printk.c:2246
 vprintk_emit+0x13a/0x610 kernel/printk/printk.c:2329
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2363
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2373
 __ext4_grp_locked_error+0x5b0/0x7b0 fs/ext4/super.c:1063
 ext4_mb_generate_buddy+0x247/0x2d0 fs/ext4/mballoc.c:1217
 ext4_mb_init_cache+0x848/0xbc0 fs/ext4/mballoc.c:1406
 ext4_mb_init_group+0x210/0x3b0 fs/ext4/mballoc.c:1543
 ext4_mb_good_group_nolock fs/ext4/mballoc.c:2704 [inline]
 ext4_mb_regular_allocator+0xb13/0x2370 fs/ext4/mballoc.c:2903
 ext4_mb_new_blocks+0x801/0x2020 fs/ext4/mballoc.c:6219
 ext4_ext_map_blocks+0x10a1/0x33b0 fs/ext4/extents.c:4318
 ext4_map_blocks+0x72a/0xf50 fs/ext4/inode.c:652
 mpage_map_one_extent fs/ext4/inode.c:2237 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2290 [inline]
 ext4_do_writepages+0xd85/0x2110 fs/ext4/inode.c:2753
 ext4_writepages+0x159/0x2e0 fs/ext4/inode.c:2842
 do_writepages+0x1d8/0x480 mm/page-writeback.c:2683
 filemap_fdatawrite_wbc+0xdb/0x100 mm/filemap.c:397
 __filemap_fdatawrite_range mm/filemap.c:430 [inline]
 file_write_and_wait_range+0xc8/0x170 mm/filemap.c:788
 generic_buffers_fsync_noflush+0x4c/0x130 fs/buffer.c:600
 ext4_fsync_nojournal fs/ext4/fsync.c:88 [inline]
 ext4_sync_file+0x20b/0x6c0 fs/ext4/fsync.c:151
 vfs_fsync_range+0x122/0x140 fs/sync.c:188
 generic_write_sync include/linux/fs.h:2822 [inline]
 ext4_buffered_write_iter+0x338/0x380 fs/ext4/file.c:305
 ext4_file_write_iter+0x29f/0xe30
 do_iter_readv_writev+0x3b0/0x470
 vfs_writev+0x2e0/0x880 fs/read_write.c:971
 do_pwritev fs/read_write.c:1072 [inline]
 __do_sys_pwritev2 fs/read_write.c:1131 [inline]
 __se_sys_pwritev2+0x10c/0x1d0 fs/read_write.c:1122
 __x64_sys_pwritev2+0x78/0x90 fs/read_write.c:1122
 x64_sys_call+0x271f/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:329
 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: 0x00000000fffff15c -> 0x00000000fffffd9b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 17134 Comm: syz.1.2757 Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
==================================================================
block bitmap and bg descriptor inconsistent: 25 vs 150994969 free clusters
EXT4-fs (loop1): Delayed block allocation failed for inode 15 at logical offset 10 with max blocks 23 with error 28
EXT4-fs (loop1): This should not happen!! Data will be lost

EXT4-fs (loop1): Total free blocks count 0
EXT4-fs (loop1): Free/Dirty block details
EXT4-fs (loop1): free_blocks=2415919104
EXT4-fs (loop1): dirty_blocks=48
EXT4-fs (loop1): Block reservation details
EXT4-fs (loop1): i_reserved_data_blocks=3
syz.1.2757 (17134) used greatest stack depth: 7240 bytes left