==================================================================
BUG: KCSAN: data-race in console_unlock / console_unlock

write to 0xffffffff8417d940 of 8 bytes by task 17218 on cpu 1:
 console_unlock+0x570/0xb30 kernel/printk/printk.c:2632
 vprintk_emit+0x125/0x3d0 kernel/printk/printk.c:2174
 vprintk_default+0x22/0x30 kernel/printk/printk.c:2185
 vprintk+0x15a/0x170 kernel/printk/printk_safe.c:392
 printk+0x62/0x87 kernel/printk/printk.c:2216
 printk_stack_address arch/x86/kernel/dumpstack.c:72 [inline]
 show_trace_log_lvl+0x587/0x600 arch/x86/kernel/dumpstack.c:282
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xb7/0x103 lib/dump_stack.c:105
 dump_stack+0x11/0x1a lib/dump_stack.c:112
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail+0x23c/0x250 lib/fault-inject.c:146
 __should_failslab+0x81/0x90 mm/failslab.c:33
 should_failslab+0x5/0x20 mm/slab_common.c:1326
 slab_pre_alloc_hook mm/slab.h:494 [inline]
 slab_alloc mm/slab.c:3306 [inline]
 kmem_cache_alloc_trace+0x49/0x310 mm/slab.c:3573
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 alloc_pipe_info+0xac/0x350 fs/pipe.c:792
 splice_direct_to_actor+0x5f7/0x650 fs/splice.c:836
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffffffff8417d940 of 8 bytes by task 17171 on cpu 0:
 console_unlock+0x9f5/0xb30 kernel/printk/printk.c:2667
 con_flush_chars+0xc1/0x400 drivers/tty/vt/vt.c:3329
 con_write+0x2a/0x40 drivers/tty/vt/vt.c:3256
 do_output_char+0x47f/0x4f0 drivers/tty/n_tty.c:444
 process_output drivers/tty/n_tty.c:511 [inline]
 n_tty_write+0x7f8/0xaf0 drivers/tty/n_tty.c:2300
 do_tty_write drivers/tty/tty_io.c:1038 [inline]
 file_tty_write+0x409/0x660 drivers/tty/tty_io.c:1110
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1131
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000000000005d9b -> 0x0000000000005d9c

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17171 Comm: syz-executor.2 Not tainted 5.14.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
sd 0:0:1:0: [sg0] tag#6584 FAILED Result: hostbyte=DID_ABORT driverbyte=DRIVER_OK cmd_age=0s
sd 0:0:1:0: [sg0] tag#6584 CDB: Access control out
sd 0:0:1:0: [sg0] tag#6584 CDB[00]: 87 92 e9 b3 61 8d 78 86 69 c2 61 3e f6 72 77 9b
sd 0:0:1:0: [sg0] tag#6584 CDB[10]: 0c 21 a1 1d 05 4c 06 31 a4 ba 78 b5 8f fd 00 8a
sd 0:0:1:0: [sg0] tag#6584 CDB[20]: 9a fb 43 9e 59 a2 5a 43 44 45 94 9c 3e 2a 97 19
sd 0:0:1:0: [sg0] tag#6584 CDB[30]: 8c bb 68 f7 dd 4c 87 2e dc 01 4c 36