syzbot

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BUG: KCSAN: data-race in ktime_get / timekeeping_update_from_shadow

write to 0xffffffff893a4488 of 304 bytes by interrupt on cpu 0:
 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
 kcsan_setup_watchpoint+0x404/0x410 kernel/kcsan/core.c:705
 scm_set_cred include/net/scm.h:73 [inline]
 unix_skb_to_scm net/unix/af_unix.c:2005 [inline]
 __unix_dgram_recvmsg+0x5ca/0x870 net/unix/af_unix.c:2638
 unix_dgram_recvmsg+0x7e/0x90 net/unix/af_unix.c:2686
 sock_recvmsg_nosec+0xc2/0xf0 net/socket.c:1137
 ____sys_recvmsg+0x26f/0x280 net/socket.c:2916
 ___sys_recvmsg+0x11f/0x3b0 net/socket.c:2960
 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 0xffffffff893a4498 of 8 bytes by task 9508 on cpu 1:
 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+0xcd9/0x1130 block/blk-mq.c:3228
 __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
 swap_writepage_bdev_async mm/page_io.c:448 [inline]
 __swap_writepage+0x997/0xdd0 mm/page_io.c:471
 swap_writeout+0x314/0x5a0 mm/page_io.c:288
 writeout mm/vmscan.c:632 [inline]
 pageout mm/vmscan.c:679 [inline]
 shrink_folio_list+0x1f73/0x2840 mm/vmscan.c:1400
 evict_folios+0x285f/0x3370 mm/vmscan.c:4854
 try_to_shrink_lruvec+0x858/0xc20 mm/vmscan.c:5009
 lru_gen_shrink_lruvec mm/vmscan.c:5173 [inline]
 shrink_lruvec+0x256/0x1bc0 mm/vmscan.c:5932
 shrink_node_memcgs mm/vmscan.c:6171 [inline]
 shrink_node+0x697/0x20a0 mm/vmscan.c:6215
 shrink_zones mm/vmscan.c:6454 [inline]
 do_try_to_free_pages+0x408/0xc90 mm/vmscan.c:6516
 try_to_free_mem_cgroup_pages+0x201/0x420 mm/vmscan.c:6838
 try_charge_memcg+0x373/0xa10 mm/memcontrol.c:2627
 obj_cgroup_charge_pages mm/memcontrol.c:3069 [inline]
 __memcg_kmem_charge_page+0x1ce/0x3d0 mm/memcontrol.c:3113
 __alloc_frozen_pages_noprof+0x18a/0x350 mm/page_alloc.c:5243
 alloc_pages_mpol+0xb3/0x260 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0x8f/0x140 mm/mempolicy.c:2581
 vm_area_alloc_pages mm/vmalloc.c:3728 [inline]
 __vmalloc_area_node mm/vmalloc.c:3878 [inline]
 __vmalloc_node_range_noprof+0xaed/0x11c0 mm/vmalloc.c:4064
 __bpf_map_area_alloc kernel/bpf/syscall.c:404 [inline]
 bpf_map_area_alloc+0xfa/0x140 kernel/bpf/syscall.c:411
 bloom_map_alloc+0x1b8/0x2c0 kernel/bpf/bloom_filter.c:146
 map_create+0x862/0xda0 kernel/bpf/syscall.c:1500
 __sys_bpf+0x5c8/0x7e0 kernel/bpf/syscall.c:6230
 __do_sys_bpf kernel/bpf/syscall.c:6361 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6359 [inline]
 __x64_sys_bpf+0x41/0x50 kernel/bpf/syscall.c:6359
 x64_sys_call+0x10cb/0x3020 arch/x86/include/generated/asm/syscalls_64.h:322
 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: 0x000000893b66a9a6 -> 0x000000893cb65b13

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 9508 Comm: syz.7.1660 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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syz.7.1660 (9508) used greatest stack depth: 7408 bytes left