syzbot

loop5: detected capacity change from 0 to 512
==================================================================
BUG: KCSAN: data-race in ktime_get / timekeeping_update_from_shadow

write to 0xffffffff893ab488 of 304 bytes by interrupt on cpu 1:
 timekeeping_update_from_shadow+0x40d/0x440 kernel/time/timekeeping.c:829
 __timekeeping_advance+0xa5d/0xc10 kernel/time/timekeeping.c:2532
 timekeeping_advance kernel/time/timekeeping.c:2540 [inline]
 update_wall_time+0x21/0x50 kernel/time/timekeeping.c:2550
 tick_do_update_jiffies64+0x169/0x1c0 kernel/time/tick-sched.c:149
 tick_sched_do_timer kernel/time/tick-sched.c:253 [inline]
 tick_nohz_handler+0x8d/0x3d0 kernel/time/tick-sched.c:312
 __run_hrtimer kernel/time/hrtimer.c:1930 [inline]
 __hrtimer_run_queues+0x276/0x4f0 kernel/time/hrtimer.c:1994
 hrtimer_interrupt+0x261/0x850 kernel/time/hrtimer.c:2113
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1067
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1061
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
 check_kcov_mode kernel/kcov.c:183 [inline]
 write_comp_data kernel/kcov.c:246 [inline]
 __sanitizer_cov_trace_const_cmp4+0x30/0x90 kernel/kcov.c:314
 __copy_msghdr net/socket.c:2590 [inline]
 copy_msghdr_from_user net/socket.c:2631 [inline]
 recvmsg_copy_msghdr net/socket.c:2884 [inline]
 ___sys_recvmsg+0x235/0x3b0 net/socket.c:2956
 do_recvmmsg+0x1ef/0x560 net/socket.c:3055
 __sys_recvmmsg net/socket.c:3129 [inline]
 __do_sys_recvmmsg net/socket.c:3152 [inline]
 __se_sys_recvmmsg net/socket.c:3145 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3145
 x64_sys_call+0x80f/0x3020 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff893ab498 of 8 bytes by task 17166 on cpu 0:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:426 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:449 [inline]
 ktime_get+0xcf/0x240 kernel/time/timekeeping.c:967
 ktime_get_ns include/linux/timekeeping.h:175 [inline]
 blk_time_get_ns block/blk.h:702 [inline]
 blk_account_io_start+0x2ef/0x3d0 block/blk-mq.c:1131
 blk_mq_bio_to_request block/blk-mq.c:2707 [inline]
 blk_mq_submit_bio+0xb6a/0x10e0 block/blk-mq.c:3214
 __submit_bio+0x103/0x4f0 block/blk-core.c:635
 __submit_bio_noacct_mq block/blk-core.c:722 [inline]
 submit_bio_noacct_nocheck+0x153/0x620 block/blk-core.c:753
 submit_bio_noacct+0x746/0x980 block/blk-core.c:884
 submit_bio+0x2a4/0x2c0 block/blk-core.c:926
 blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline]
 submit_bh_wbc+0x2e0/0x320 fs/buffer.c:2737
 submit_bh+0x1e/0x30 fs/buffer.c:2742
 __ext4_read_bh fs/ext4/super.c:181 [inline]
 ext4_read_bh_nowait fs/ext4/super.c:193 [inline]
 ext4_read_bh_lock+0x151/0x170 fs/ext4/super.c:218
 ext4_bread_batch+0x173/0x320 fs/ext4/inode.c:1087
 ext4_xattr_inode_read+0x11f/0x2e0 fs/ext4/xattr.c:398
 ext4_xattr_inode_get+0xee/0x240 fs/ext4/xattr.c:551
 ext4_xattr_move_to_block fs/ext4/xattr.c:2644 [inline]
 ext4_xattr_make_inode_space fs/ext4/xattr.c:2746 [inline]
 ext4_expand_extra_isize_ea+0x8c0/0x11a0 fs/ext4/xattr.c:2834
 __ext4_expand_extra_isize+0x246/0x280 fs/ext4/inode.c:6434
 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6477 [inline]
 __ext4_mark_inode_dirty+0x29b/0x3d0 fs/ext4/inode.c:6555
 ext4_evict_inode+0x8ba/0xe30 fs/ext4/inode.c:267
 evict+0x2af/0x510 fs/inode.c:841
 iput_final fs/inode.c:1960 [inline]
 iput+0x41a/0x580 fs/inode.c:2009
 ext4_process_orphan+0x1a9/0x1c0 fs/ext4/orphan.c:358
 ext4_orphan_cleanup+0x69c/0x9f0 fs/ext4/orphan.c:472
 __ext4_fill_super fs/ext4/super.c:5701 [inline]
 ext4_fill_super+0x3408/0x37c0 fs/ext4/super.c:5824
 get_tree_bdev_flags+0x291/0x300 fs/super.c:1694
 get_tree_bdev+0x1f/0x30 fs/super.c:1717
 ext4_get_tree+0x1c/0x30 fs/ext4/super.c:5856
 vfs_get_tree+0x57/0x1d0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x288/0x8d0 fs/namespace.c:3834
 path_mount+0x4d0/0xbc0 fs/namespace.c:4154
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4360
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4360
 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x000002570b88c295 -> 0x000002570cd87402

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 17166 Comm: syz.5.3505 Tainted: G        W           syzkaller #0 PREEMPT(full) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
==================================================================
EXT4-fs (loop5): 1 orphan inode deleted
EXT4-fs (loop5): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none.