==================================================================
BUG: KCSAN: data-race in data_alloc / prb_reserve

write to 0xffffffff860801c0 of 8 bytes by task 14328 on cpu 0:
 data_alloc+0x291/0x2c0 kernel/printk/printk_ringbuffer.c:1096
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2266
 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2326
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2360
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2370
 __ext4_error+0x221/0x310 fs/ext4/super.c:822
 ext4_orphan_get+0x172/0x3e0 fs/ext4/ialloc.c:1397
 ext4_orphan_cleanup+0x5df/0x9e0 fs/ext4/orphan.c:467
 __ext4_fill_super fs/ext4/super.c:5553 [inline]
 ext4_fill_super+0x367a/0x39e0 fs/ext4/super.c:5676
 get_tree_bdev+0x253/0x2e0 fs/super.c:1615
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5708
 vfs_get_tree+0x56/0x1d0 fs/super.c:1780
 do_new_mount+0x227/0x690 fs/namespace.c:3352
 path_mount+0x49b/0xb30 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3875
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3875
 x64_sys_call+0x25c9/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:166
 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

read to 0xffffffff860801c0 of 8 bytes by task 14326 on cpu 1:
 desc_read kernel/printk/printk_ringbuffer.c:482 [inline]
 desc_push_tail kernel/printk/printk_ringbuffer.c:778 [inline]
 desc_reserve kernel/printk/printk_ringbuffer.c:924 [inline]
 prb_reserve+0x235/0xb60 kernel/printk/printk_ringbuffer.c:1619
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2266
 vprintk_emit+0x10c/0x5e0 kernel/printk/printk.c:2326
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2360
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:45
 _printk+0x7a/0xa0 kernel/printk/printk.c:2370
 __ext4_error+0x221/0x310 fs/ext4/super.c:822
 ext4_orphan_get+0x172/0x3e0 fs/ext4/ialloc.c:1397
 ext4_orphan_cleanup+0x5df/0x9e0 fs/ext4/orphan.c:467
 __ext4_fill_super fs/ext4/super.c:5553 [inline]
 ext4_fill_super+0x367a/0x39e0 fs/ext4/super.c:5676
 get_tree_bdev+0x253/0x2e0 fs/super.c:1615
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5708
 vfs_get_tree+0x56/0x1d0 fs/super.c:1780
 do_new_mount+0x227/0x690 fs/namespace.c:3352
 path_mount+0x49b/0xb30 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount+0x27f/0x2d0 fs/namespace.c:3875
 __x64_sys_mount+0x67/0x80 fs/namespace.c:3875
 x64_sys_call+0x25c9/0x2d70 arch/x86/include/generated/asm/syscalls_64.h:166
 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: 0x000000000025c3c8 -> 0x0000000000319530

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 14326 Comm: syz-executor.4 Tainted: G        W          6.10.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
==================================================================
EXT4-fs error (device loop4): ext4_orphan_get:1399: comm syz-executor.4: couldn't read orphan inode 12 (err -117)
EXT4-fs (loop4): mounted filesystem 00000005-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.
EXT4-fs (loop4): unmounting filesystem 00000005-0000-0000-0000-000000000000.