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BUG: KCSAN: data-race in ktime_get / timekeeping_update_from_shadow

write to 0xffffffff893da4c8 of 304 bytes by interrupt on cpu 0:
 timekeeping_update_from_shadow+0x40d/0x440 kernel/time/timekeeping.c:835
 __timekeeping_advance+0xa68/0xc10 kernel/time/timekeeping.c:2614
 timekeeping_advance kernel/time/timekeeping.c:2622 [inline]
 update_wall_time+0x21/0x50 kernel/time/timekeeping.c:2632
 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+0x88/0x380 kernel/time/tick-sched.c:310
 __run_hrtimer kernel/time/hrtimer.c:2032 [inline]
 __hrtimer_run_queues+0x1f8/0x510 kernel/time/hrtimer.c:2096
 hrtimer_interrupt+0x257/0x810 kernel/time/hrtimer.c:2215
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1051 [inline]
 __sysvec_apic_timer_interrupt+0x5f/0x1c0 arch/x86/kernel/apic/apic.c:1068
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x6f/0x80 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
 is_atomic kernel/kcsan/core.c:260 [inline]
 should_watch kernel/kcsan/core.c:277 [inline]
 check_access kernel/kcsan/core.c:752 [inline]
 __tsan_read8+0xfb/0x190 kernel/kcsan/core.c:1025
 copy_msghdr_from_user net/socket.c:2622 [inline]
 recvmsg_copy_msghdr net/socket.c:2870 [inline]
 ___sys_recvmsg+0x368/0x3a0 net/socket.c:2942
 do_recvmmsg+0x1e5/0x560 net/socket.c:3041
 __sys_recvmmsg net/socket.c:3115 [inline]
 __do_sys_recvmmsg net/socket.c:3138 [inline]
 __se_sys_recvmmsg net/socket.c:3131 [inline]
 __x64_sys_recvmmsg+0xe5/0x170 net/socket.c:3131
 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+0x136/0x3c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff893da4d8 of 8 bytes by task 5157 on cpu 1:
 timekeeping_cycles_to_ns kernel/time/timekeeping.c:432 [inline]
 timekeeping_get_ns kernel/time/timekeeping.c:455 [inline]
 ktime_get+0xcf/0x240 kernel/time/timekeeping.c:973
 ktime_get_ns include/linux/timekeeping.h:175 [inline]
 blk_time_get_ns block/blk.h:734 [inline]
 blk_account_io_start+0x373/0x440 block/blk-mq.c:1100
 blk_mq_bio_to_request block/blk-mq.c:2676 [inline]
 blk_mq_submit_bio+0xbb2/0x1130 block/blk-mq.c:3182
 __submit_bio+0x54/0x3d0 block/blk-core.c:673
 __submit_bio_noacct_mq block/blk-core.c:756 [inline]
 submit_bio_noacct_nocheck+0x153/0x620 block/blk-core.c:790
 submit_bio_noacct+0x700/0x920 block/blk-core.c:921
 submit_bio+0x2a4/0x2c0 block/blk-core.c:962
 blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline]
 ext4_io_submit fs/ext4/page-io.c:404 [inline]
 io_submit_add_bh fs/ext4/page-io.c:461 [inline]
 ext4_bio_write_folio+0x702/0xa10 fs/ext4/page-io.c:609
 mpage_submit_folio fs/ext4/inode.c:2104 [inline]
 mpage_process_page_bufs+0x487/0x600 fs/ext4/inode.c:2215
 mpage_prepare_extent_to_map+0x79e/0xc00 fs/ext4/inode.c:2754
 ext4_do_writepages+0x6ec/0x2720 fs/ext4/inode.c:2895
 ext4_writepages+0x18f/0x300 fs/ext4/inode.c:3043
 do_writepages+0x1b9/0x300 mm/page-writeback.c:2571
 __writeback_single_inode+0x7b/0x660 fs/fs-writeback.c:1787
 writeback_sb_inodes+0x4d9/0xaa0 fs/fs-writeback.c:2079
 __writeback_inodes_wb+0x8a/0x180 fs/fs-writeback.c:2155
 wb_writeback+0x21e/0x510 fs/fs-writeback.c:2266
 wb_check_old_data_flush fs/fs-writeback.c:2370 [inline]
 wb_do_writeback fs/fs-writeback.c:2449 [inline]
 wb_workfn+0x740/0xa50 fs/fs-writeback.c:2477
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x221/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x000000954ecd53ae -> 0x00000095501d051b

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 5157 Comm: kworker/u8:18 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: writeback wb_workfn (flush-8:0)
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