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

write to 0xffffffff86724a60 of 8 bytes by task 20814 on cpu 1:
 prb_reserve+0x740/0xb60
 vprintk_store+0x53f/0x810 kernel/printk/printk.c:2301
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2383
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2422
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:68
 _printk+0x7a/0xa0 kernel/printk/printk.c:2432
 mnt_warn_timestamp_expiry+0x1cd/0x210 fs/namespace.c:2961
 do_new_mount_fc fs/namespace.c:3442 [inline]
 do_new_mount+0x316/0x690 fs/namespace.c:3509
 path_mount+0x49b/0xb30 fs/namespace.c:3834
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x27c/0x2d0 fs/namespace.c:4034
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4034
 x64_sys_call+0x203e/0x2d60 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 0xffffffff86724a60 of 8 bytes by task 20827 on cpu 0:
 desc_read kernel/printk/printk_ringbuffer.c:486 [inline]
 prb_first_seq kernel/printk/printk_ringbuffer.c:1957 [inline]
 _prb_read_valid+0x3bb/0xba0 kernel/printk/printk_ringbuffer.c:2114
 prb_read_valid+0x3d/0x60 kernel/printk/printk_ringbuffer.c:2182
 __console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
 console_unlock+0x175/0x330 kernel/printk/printk.c:3279
 con_install+0x28d/0x2d0 drivers/tty/vt/vt.c:3547
 tty_driver_install_tty drivers/tty/tty_io.c:1304 [inline]
 tty_init_dev+0x7b/0x320 drivers/tty/tty_io.c:1416
 tty_open_by_driver drivers/tty/tty_io.c:2082 [inline]
 tty_open+0x6c7/0xb00 drivers/tty/tty_io.c:2129
 chrdev_open+0x2f9/0x370 fs/char_dev.c:414
 do_dentry_open+0x621/0xa20 fs/open.c:958
 vfs_open+0x38/0x1f0 fs/open.c:1088
 do_open fs/namei.c:3774 [inline]
 path_openat+0x1ac2/0x1fa0 fs/namei.c:3933
 do_filp_open+0xf7/0x200 fs/namei.c:3960
 do_sys_openat2+0xab/0x120 fs/open.c:1415
 do_sys_open fs/open.c:1430 [inline]
 __do_sys_openat fs/open.c:1446 [inline]
 __se_sys_openat fs/open.c:1441 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1441
 x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
 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: 0x0000000000001a48 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 20827 Comm: syz.3.5786 Not tainted 6.12.0-rc5-syzkaller-00176-g5635f189425e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================
loop3: detected capacity change from 0 to 512
loop3: detected capacity change from 0 to 1764
iso9660: Bad value for 'uid'
iso9660: Bad value for 'uid'