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KCSAN: data-race in kvm_mmu_page_fault / kvm_set_memslot (2)

Status: auto-closed as invalid on 2021/03/15 00:57
Subsystems: kvm
[Documentation on labels]
First crash: 1145d, last: 1145d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in kvm_mmu_page_fault / kvm_set_memslot kvm 1 1247d 1247d 0/26 auto-closed as invalid on 2020/12/02 20:10

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

write to 0xffff8880433a5800 of 8 bytes by task 3211 on cpu 1:
 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 0xffff8880433a5800 of 8 bytes by task 3177 on cpu 0:
 mmio_info_in_cache arch/x86/kvm/mmu/mmu.c:3483 [inline]
 kvm_mmu_page_fault+0x206/0x3c0 arch/x86/kvm/mmu/mmu.c:5109
 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: 0 PID: 3177 Comm: syz-executor.3 Not tainted 5.11.0-rc6-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
2021/02/08 00:56 upstream b75dba7f472c 2ce644fc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in kvm_mmu_page_fault / kvm_set_memslot
* Struck through repros no longer work on HEAD.