syzbot


KCSAN: data-race in kvm_arch_vcpu_load / kvm_vcpu_kick (2)
Status: auto-closed as invalid on 2020/12/05 18:11
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 575d, last: 572d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in kvm_arch_vcpu_load / kvm_vcpu_kick (4) 1 411d 387d 0/22 auto-closed as invalid on 2021/05/18 19:52
upstream KCSAN: data-race in kvm_arch_vcpu_load / kvm_vcpu_kick (3) 1 479d 479d 0/22 auto-closed as invalid on 2021/03/08 08:59
upstream KCSAN: data-race in kvm_arch_vcpu_load / kvm_vcpu_kick 1 617d 617d 0/22 auto-closed as invalid on 2020/10/21 04:02

Sample crash report:
==================================================================
BUG: KCSAN: data-race in kvm_arch_vcpu_load / kvm_vcpu_kick

write to 0xffff888023b10420 of 4 bytes by task 14705 on cpu 0:
 kvm_arch_vcpu_load+0x423/0x590 arch/x86/kvm/x86.c:3931
 vcpu_load+0x34/0x70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:208
 kvm_arch_vcpu_ioctl_set_regs+0x16/0x30 arch/x86/kvm/x86.c:9360
 kvm_vcpu_ioctl+0x4ca/0x8f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3264
 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

read to 0xffff888023b10420 of 4 bytes by task 14671 on cpu 1:
 kvm_vcpu_kick+0x15/0x150 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2859
 kvm_arch_memslots_updated+0x85/0xc0 arch/x86/kvm/x86.c:10502
 install_new_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:1144 [inline]
 kvm_set_memslot+0x93d/0xa00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1222
 __kvm_set_memory_region+0x708/0x910 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1374
 kvm_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1395 [inline]
 kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1407 [inline]
 kvm_vm_ioctl+0x822/0x17d0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3708
 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: 14671 Comm: syz-executor.5 Not tainted 5.10.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2020/10/31 18:03 upstream 5fc6b075e165 8bc4594f .config log report info
ci2-upstream-kcsan-gce 2020/10/28 20:57 upstream ed8780e3f2ec f24824d3 .config log report info