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BUG: KCSAN: data-race in console_unlock / console_unlock

write to 0xffffffff8417c940 of 8 bytes by task 9231 on cpu 0:
 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
 prepare_alloc_pages mm/page_alloc.c:5172 [inline]
 __alloc_pages+0x102/0x320 mm/page_alloc.c:5380
 alloc_pages+0x2e8/0x340 mm/mempolicy.c:2244
 __pte_alloc_one include/asm-generic/pgalloc.h:63 [inline]
 pte_alloc_one+0x29/0xb0 arch/x86/mm/pgtable.c:33
 __pte_alloc+0x2f/0x210 mm/memory.c:439
 do_anonymous_page+0x79b/0x8a0 mm/memory.c:3735
 handle_pte_fault mm/memory.c:4556 [inline]
 __handle_mm_fault mm/memory.c:4693 [inline]
 handle_mm_fault+0x98f/0x1a50 mm/memory.c:4791
 do_user_addr_fault+0x609/0xbe0 arch/x86/mm/fault.c:1390
 handle_page_fault arch/x86/mm/fault.c:1475 [inline]
 exc_page_fault+0x91/0x220 arch/x86/mm/fault.c:1531
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:568
 copy_user_generic_unrolled+0x86/0xc0 arch/x86/lib/copy_user_64.S:90
 copy_user_generic arch/x86/include/asm/uaccess_64.h:37 [inline]
 raw_copy_from_user arch/x86/include/asm/uaccess_64.h:52 [inline]
 _copy_from_user+0x7e/0xd0 lib/usercopy.c:16
 copy_from_user include/linux/uaccess.h:192 [inline]
 vt_do_kbkeycode_ioctl+0x35/0x1b0 drivers/tty/vt/keyboard.c:1895
 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:419 [inline]
 vt_ioctl+0x747/0x2060 drivers/tty/vt/vt_ioctl.c:750
 tty_ioctl+0xa24/0x1120 drivers/tty/tty_io.c:2805
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:1069 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:1055
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055
 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 0xffffffff8417c940 of 8 bytes by task 9251 on cpu 1:
 console_unlock+0x9f5/0xb30 kernel/printk/printk.c:2667
 con_install+0x297/0x2d0 drivers/tty/vt/vt.c:3371
 tty_driver_install_tty drivers/tty/tty_io.c:1315 [inline]
 tty_init_dev+0x76/0x340 drivers/tty/tty_io.c:1429
 tty_open_by_driver drivers/tty/tty_io.c:2098 [inline]
 tty_open+0x70c/0xb60 drivers/tty/tty_io.c:2146
 chrdev_open+0x39c/0x420 fs/char_dev.c:414
 do_dentry_open+0x529/0x850 fs/open.c:826
 vfs_open+0x43/0x50 fs/open.c:949
 do_open fs/namei.c:3374 [inline]
 path_openat+0x1787/0x1f20 fs/namei.c:3507
 do_filp_open+0xe9/0x200 fs/namei.c:3534
 do_sys_openat2+0xa3/0x250 fs/open.c:1204
 do_sys_open fs/open.c:1220 [inline]
 __do_sys_openat fs/open.c:1236 [inline]
 __se_sys_openat fs/open.c:1231 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1231
 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: 0x000000000000c57f -> 0x000000000000c580

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 9251 Comm: syz-executor.1 Not tainted 5.14.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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