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: 8d02h, last: 52m
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 (63):
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
2026/02/19 10:27 upstream 956b9cbd7f15 746545b8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/19 00:18 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/18 18:19 upstream 2961f841b025 77d4d919 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/18 10:44 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/18 06:38 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/18 02:42 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/18 00:03 upstream d295082ea672 39751c21 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/16 12:20 upstream 0f2acd3148e0 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
2026/02/16 06:39 upstream bb7a3fc2c976 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
2026/02/16 06:19 upstream bb7a3fc2c976 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
2026/02/16 06:19 upstream bb7a3fc2c976 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
2026/02/16 01:12 upstream bb7a3fc2c976 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
2026/02/15 15:23 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
2026/02/15 11:55 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
2026/02/15 10:21 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
2026/02/15 08:54 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
2026/02/15 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
2026/02/15 05:05 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
2026/02/13 11:20 upstream cee73b1e840c 6a673c50 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/13 00:49 upstream 37a93dd5c49b 504cb1bf .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/12 14:28 upstream c22e26bd0906 76a109e2 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-root KMSAN: uninit-value in __flush_smp_call_function_queue
2026/02/12 12:49 upstream c22e26bd0906 76a109e2 .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 23:20 upstream 192c0159402e 75707236 .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
2026/02/18 22:04 upstream 2961f841b025 77d4d919 .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
2026/02/18 21:02 upstream 2961f841b025 77d4d919 .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
2026/02/18 09:02 upstream d295082ea672 39751c21 .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
2026/02/18 07:49 upstream d295082ea672 39751c21 .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
2026/02/17 14:45 upstream 970296997869 e439b951 .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
2026/02/17 13:43 upstream 970296997869 e439b951 .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
2026/02/17 11:08 upstream 970296997869 e439b951 .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
2026/02/16 23:21 upstream 0f2acd3148e0 5d52cba5 .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
2026/02/16 13:26 upstream 26a4cfaff82a 1e62d198 .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
2026/02/16 12:01 upstream 26a4cfaff82a 1e62d198 .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
2026/02/16 11:51 upstream 26a4cfaff82a 1e62d198 .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
2026/02/16 11:11 upstream 26a4cfaff82a 1e62d198 .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
2026/02/16 07:27 upstream 26a4cfaff82a 1e62d198 .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
2026/02/15 18:34 upstream ca4ee40bf13d 1e62d198 .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
2026/02/15 10:42 upstream 64275e9fda37 1e62d198 .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
2026/02/15 09:41 upstream 64275e9fda37 1e62d198 .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
2026/02/15 08:53 upstream 64275e9fda37 1e62d198 .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
2026/02/15 07:52 upstream 64275e9fda37 1e62d198 .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
2026/02/14 18:21 upstream 770aaedb461a 1e62d198 .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
2026/02/14 15:31 upstream 770aaedb461a 1e62d198 .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
2026/02/14 07:01 upstream cd7a5651db26 1e62d198 .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
2026/02/14 06:32 upstream cd7a5651db26 1e62d198 .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
2026/02/14 06:28 upstream cd7a5651db26 1e62d198 .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
2026/02/14 05:16 upstream cd7a5651db26 1e62d198 .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
2026/02/13 15:16 upstream cee73b1e840c 6a673c50 .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
2026/02/13 14:49 upstream cee73b1e840c 6a673c50 .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
2026/02/13 12:58 upstream cee73b1e840c 6a673c50 .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
2026/02/12 12:55 upstream c22e26bd0906 76a109e2 .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
2026/02/12 08:35 upstream c22e26bd0906 76a109e2 .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
2026/02/11 10:37 upstream dc855b77719f 441e25b7 .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
2026/02/11 09:48 upstream dc855b77719f 441e25b7 .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.