KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot (3)

Status: auto-closed as invalid on 2021/03/19 14:24
Subsystems: kvm
[Documentation on labels]
First crash: 2043d, last: 2009d
▶ ▼ Similar bugs (3)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot kvm 6 3 2140d 2152d 0/29 auto-closed as invalid on 2020/11/08 13:13
upstream KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot (2) kvm 6 1 2085d 2076d 0/29 auto-closed as invalid on 2021/01/02 05:15
upstream KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot (4) kvm 6 1 1969d 1969d 0/29 auto-closed as invalid on 2021/04/27 19:30

Sample crash report:
==================================================================
BUG: KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot

write to 0xffff88802d8ba000 of 8 bytes by task 10861 on cpu 0:
 install_new_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:1148 [inline]
 kvm_set_memslot+0x958/0xa10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1224
 __kvm_set_memory_region+0x794/0x930 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1377
 kvm_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1398 [inline]
 kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1410 [inline]
 kvm_vm_ioctl+0xacb/0x1c40 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3825
 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 0xffff88802d8ba000 of 8 bytes by task 10854 on cpu 1:
 mmio_info_in_cache arch/x86/kvm/mmu/mmu.c:3483 [inline]
 handle_mmio_page_fault+0x9d/0x8d0 arch/x86/kvm/mmu/mmu.c:3583
 kvm_mmu_page_fault+0x348/0x3c0 arch/x86/kvm/mmu/mmu.c:5068
 handle_ept_misconfig+0x96/0x150 arch/x86/kvm/vmx/vmx.c:5355
 vmx_handle_exit+0x2fd/0x800 arch/x86/kvm/vmx/vmx.c:6048
 vcpu_enter_guest+0x1a2b/0x2470 arch/x86/kvm/x86.c:9089
 vcpu_run+0x24e/0x690 arch/x86/kvm/x86.c:9155
 kvm_arch_vcpu_ioctl_run+0x466/0x850 arch/x86/kvm/x86.c:9382
 kvm_vcpu_ioctl+0x562/0x8f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3283
 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: 10854 Comm: syz-executor.0 Not tainted 5.11.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/02/12 14:19 upstream dcc0b49040c7 a5f86b15 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot
2021/01/08 21:07 upstream 6279d812eab6 c104d4a3 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.