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KCSAN: data-race in kvm_cpu_has_injectable_intr / kvm_pic_set_irq (2)

Status: auto-closed as invalid on 2020/10/21 12:42
Subsystems: kvm
[Documentation on labels]
First crash: 1317d, last: 1317d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in kvm_cpu_has_injectable_intr / kvm_pic_set_irq (3) kvm 1 1216d 1216d 0/26 auto-closed as invalid on 2021/01/31 06:24
upstream KCSAN: data-race in kvm_cpu_has_injectable_intr / kvm_pic_set_irq kvm 1 1395d 1395d 0/26 auto-closed as invalid on 2020/08/04 12:25

Sample crash report:
==================================================================
BUG: KCSAN: data-race in kvm_cpu_has_injectable_intr / kvm_pic_set_irq

write to 0xffff88811e5ffc58 of 4 bytes by task 12248 on cpu 0:
 pic_irq_request arch/x86/kvm/i8259.c:567 [inline]
 pic_update_irq arch/x86/kvm/i8259.c:176 [inline]
 kvm_pic_set_irq+0x62c/0x8a0 arch/x86/kvm/i8259.c:196
 kvm_set_pic_irq+0x44/0x50 arch/x86/kvm/irq_comm.c:35
 kvm_set_irq+0x1cd/0x340 arch/x86/kvm/../../../virt/kvm/irqchip.c:89
 pit_do_work+0x90/0x180 arch/x86/kvm/i8254.c:250
 kthread_worker_fn+0x283/0x3b0 kernel/kthread.c:708
 kthread+0x20d/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff88811e5ffc58 of 4 bytes by task 12242 on cpu 1:
 kvm_cpu_has_extint arch/x86/kvm/irq.c:51 [inline]
 kvm_cpu_has_injectable_intr+0xbc/0x1c0 arch/x86/kvm/irq.c:78
 inject_pending_event+0x9cd/0xd10 arch/x86/kvm/x86.c:7926
 vcpu_enter_guest+0x410/0x2660 arch/x86/kvm/x86.c:8486
 vcpu_run+0x26e/0x740 arch/x86/kvm/x86.c:8706
 kvm_arch_vcpu_ioctl_run+0x38d/0x6a0 arch/x86/kvm/x86.c:8923
 kvm_vcpu_ioctl+0x565/0x950 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3230
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:739
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:739
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 12242 Comm: syz-executor.5 Not tainted 5.9.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/09/16 12:40 upstream fc4f28bb3daf 18d7d030 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.