syzbot


KMSAN: uninit-value in __flush_smp_call_function_queue

Status: upstream: reported C repro on 2026/02/15 08:48
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+4b1bd55fba6260160779@syzkaller.appspotmail.com
First crash: 101d, last: 8h16m
Discussions (2)
Title Replies (including bot) Last reply
[PATCH] sched/psi: initialize *flags in psi_memstall_enter when PSI is disabled 5 (5) 2026/04/08 16:58
[syzbot] [kernel?] KMSAN: uninit-value in __flush_smp_call_function_queue 1 (4) 2026/03/10 07:17
Last patch testing requests (5)
Created Duration User Patch Repo Result
2026/04/29 17:23 46m retest repro upstream report log
2026/04/29 17:23 30m retest repro upstream report log
2026/04/29 17:23 38m retest repro upstream report log
2026/04/29 17:23 40m retest repro upstream report log
2026/03/10 06:48 27m wangqing7171@gmail.com patch upstream report log

Sample crash report:
=====================================================
BUG: KMSAN: uninit-value in __flush_smp_call_function_queue+0x362/0x18e0 kernel/smp.c:535
 __flush_smp_call_function_queue+0x362/0x18e0 kernel/smp.c:535
 generic_smp_call_function_single_interrupt+0x1c/0x30 kernel/smp.c:463
 __sysvec_call_function_single+0x4b/0x3e0 arch/x86/kernel/smp.c:271
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:266 [inline]
 sysvec_call_function_single+0x7c/0x90 arch/x86/kernel/smp.c:266
 asm_sysvec_call_function_single+0x1f/0x30 arch/x86/include/asm/idtentry.h:704
 smap_save mm/kmsan/instrumentation.c:94 [inline]
 get_shadow_origin_ptr mm/kmsan/instrumentation.c:35 [inline]
 __msan_metadata_ptr_for_load_8+0x14/0x40 mm/kmsan/instrumentation.c:94
 find_next_bit include/linux/find.h:69 [inline]
 __for_each_wrap include/linux/find.h:477 [inline]
 steal_cookie_task kernel/sched/core.c:6305 [inline]
 sched_core_balance+0x17f2/0x2010 kernel/sched/core.c:6333
 do_balance_callbacks kernel/sched/core.c:4929 [inline]
 __balance_callbacks kernel/sched/core.c:4985 [inline]
 finish_lock_switch kernel/sched/core.c:5034 [inline]
 finish_task_switch+0x3e4/0x8b0 kernel/sched/core.c:5153
 context_switch kernel/sched/core.c:5301 [inline]
 __schedule+0x2607/0x8640 kernel/sched/core.c:6911
 schedule_idle+0x5a/0x90 kernel/sched/core.c:7034
 do_idle+0x859/0x870 kernel/sched/idle.c:369
 cpu_startup_entry+0x5f/0x80 kernel/sched/idle.c:439
 rest_init+0x1df/0x260 init/main.c:760
 start_kernel+0x6d1/0x8b0 init/main.c:1210
 x86_64_start_reservations+0x28/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x139/0x140 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x147

Local variable pflags created at:
 try_charge_memcg+0x63/0x1c20 mm/memcontrol.c:2367
 try_charge mm/memcontrol.c:2556 [inline]
 charge_memcg mm/memcontrol.c:4744 [inline]
 __mem_cgroup_charge+0x114/0x5c0 mm/memcontrol.c:4761

CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
=====================================================

Crashes (867):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/03/20 05:41 upstream 8a30aeb0d1b4 bd6dcb30 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/20 03:49 upstream 8a30aeb0d1b4 bd6dcb30 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/20 02:18 upstream 8a30aeb0d1b4 bd6dcb30 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/15 19:04 upstream ca4ee40bf13d 1e62d198 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/23 21:00 upstream 79bd2dded182 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/23 18:22 upstream 79bd2dded182 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/23 12:59 upstream cca95436be15 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/23 03:31 upstream cca95436be15 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/22 19:09 upstream 6779b50faa56 e16cf9f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/22 12:40 upstream 6779b50faa56 e16cf9f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/22 08:45 upstream 6779b50faa56 e195359d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/21 22:39 upstream 8bc67e4db64a e195359d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/21 09:36 upstream df685633c3db 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/21 04:20 upstream df685633c3db 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/20 19:33 upstream 27fa82620cba 62fb93a2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/20 14:37 upstream 27fa82620cba 62fb93a2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/20 13:26 upstream 27fa82620cba 62fb93a2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/19 20:37 upstream ab5fce87a778 223544dc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/19 07:56 upstream 4d3a2a466b8d 9f74d399 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/18 19:21 upstream 5200f5f493f7 55156e84 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/18 04:45 upstream e5d505e3664b de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/17 15:25 upstream 6916d5703ddf de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/17 14:23 upstream 6916d5703ddf de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/17 09:24 upstream 6916d5703ddf de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/17 05:41 upstream 6916d5703ddf de5aae85 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/16 20:47 upstream 6916d5703ddf a15a64a6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/16 08:25 upstream d458a240344c 81fb92f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/15 15:46 upstream 70eda68668d1 9cd3beaa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/14 19:00 upstream e1914add2799 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/14 11:18 upstream e1914add2799 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/14 04:23 upstream e1914add2799 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/13 08:17 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/13 05:14 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/13 03:25 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/13 00:25 upstream c21b90f77687 a0949470 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/12 13:41 upstream 50897c955902 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/12 12:16 upstream 50897c955902 d5b1a17d .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/12 08:03 upstream 50897c955902 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/11 06:53 upstream aa54b1d27fe0 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/15 07:56 upstream ca4ee40bf13d 1e62d198 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/11 08:40 upstream dc855b77719f 441e25b7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/23 10:58 upstream 45255ea1ca09 c69befb3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/22 17:10 upstream 6779b50faa56 e16cf9f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/21 05:29 upstream df685633c3db 41b8c833 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/20 17:28 upstream 27fa82620cba 62fb93a2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/19 19:12 upstream ab5fce87a778 223544dc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/18 17:40 upstream 5200f5f493f7 55156e84 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/16 17:46 upstream 6916d5703ddf a15a64a6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/16 04:46 upstream d458a240344c 81fb92f3 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/15 07:27 upstream 66182ca873a4 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/14 06:36 upstream e1914add2799 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/11 14:18 upstream 5d6919055dec e6eb7c0b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/05/11 05:23 upstream aa54b1d27fe0 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in __flush_smp_call_function_queue
* Struck through repros no longer work on HEAD.