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: 21d, last: 1h43m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] KMSAN: uninit-value in __flush_smp_call_function_queue 0 (2) 2026/02/15 19:05

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
 native_irq_enable arch/x86/include/asm/irqflags.h:42 [inline]
 arch_local_irq_enable arch/x86/include/asm/irqflags.h:119 [inline]
 raw_spin_rq_unlock_irq kernel/sched/sched.h:1629 [inline]
 finish_lock_switch kernel/sched/core.c:5032 [inline]
 finish_task_switch+0x11b/0x8b0 kernel/sched/core.c:5150
 context_switch kernel/sched/core.c:5298 [inline]
 __schedule+0x273e/0x8650 kernel/sched/core.c:6907
 schedule_idle+0x5a/0x90 kernel/sched/core.c:7030
 do_idle+0x748/0x760 kernel/sched/idle.c:360
 cpu_startup_entry+0x5f/0x80 kernel/sched/idle.c:430
 start_secondary+0xcc/0xd0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x147

Local variable reuse.i created at:
 mas_wr_node_store lib/maple_tree.c:3495 [inline]
 mas_wr_store_entry+0x14bd/0x96d0 lib/maple_tree.c:3764
 mas_store_prealloc+0x1834/0x1e60 lib/maple_tree.c:5169

CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
=====================================================

Crashes (186):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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
2026/03/04 21:01 upstream 0031c06807cf e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/04 13:21 upstream 0031c06807cf e6b6b96b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/04 10:19 upstream 0031c06807cf 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/04 06:07 upstream 0031c06807cf 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/04 03:43 upstream 0031c06807cf 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/03 18:08 upstream af4e9ef3d784 4180d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/03 11:41 upstream af4e9ef3d784 28b83e23 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/02 22:47 upstream 11439c4635ed b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/02 20:57 upstream 11439c4635ed b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/02 17:25 upstream 11439c4635ed b9dd6534 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/02 05:33 upstream e2bd1b136926 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/02 03:27 upstream e2bd1b136926 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 22:01 upstream eb71ab2bf722 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 20:57 upstream eb71ab2bf722 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 16:29 upstream eb71ab2bf722 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 15:07 upstream eb71ab2bf722 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 14:28 upstream eb71ab2bf722 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 09:39 upstream 42eb01783091 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/03/01 04:53 upstream 42eb01783091 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/28 16:51 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/28 15:45 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/28 11:43 upstream 4d349ee5c778 43249bac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/27 14:27 upstream a75cb869a8cc a2f13f71 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/27 01:42 upstream f4d0ec0aa20d ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/26 21:35 upstream f4d0ec0aa20d ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/26 19:42 upstream f4d0ec0aa20d ffa54287 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/26 11:56 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/26 09:45 upstream d9d32e5bd5a4 e0f78d93 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/25 17:41 upstream 7dff99b35460 df2e85d4 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/25 05:24 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/25 03:26 upstream 7dff99b35460 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/24 19:00 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/24 14:23 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/24 08:25 upstream 7dff99b35460 41d2fa6a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/24 02:17 upstream 7dff99b35460 41d2fa6a .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
2026/03/04 19:03 upstream 0031c06807cf e6b6b96b .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
2026/03/03 20:07 upstream af4e9ef3d784 4180d919 .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
2026/03/02 07:14 upstream e2bd1b136926 43249bac .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
2026/02/28 19:49 upstream 4d349ee5c778 43249bac .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
2026/02/27 21:08 upstream a75cb869a8cc 2cf092b8 .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
2026/02/27 11:18 upstream a75cb869a8cc a2f13f71 .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
2026/02/27 11:15 upstream a75cb869a8cc a2f13f71 .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
2026/02/25 20:02 upstream 7dff99b35460 df2e85d4 .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
2026/02/25 11:10 upstream 7dff99b35460 787dfb7c .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
2026/02/24 23:33 upstream 7dff99b35460 96b1aa46 .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
2026/02/24 10:29 upstream 7dff99b35460 41d2fa6a .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.