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KCSAN: data-race in kvm_mmu_page_fault / kvm_set_memslot

Status: auto-closed as invalid on 2020/12/02 20:10
Subsystems: kvm
[Documentation on labels]
First crash: 1742d, last: 1742d
Similar bugs (1)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in kvm_mmu_page_fault / kvm_set_memslot (2) kvm 6 1 1640d 1640d 0/29 auto-closed as invalid on 2021/03/15 00:57

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

write to 0xffff88810da86000 of 8 bytes by task 19323 on cpu 0:
 install_new_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:1146 [inline]
 kvm_set_memslot+0x945/0xa00 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

read to 0xffff88810da86000 of 8 bytes by task 19310 on cpu 1:
 mmio_info_in_cache arch/x86/kvm/mmu/mmu.c:3473 [inline]
 kvm_mmu_page_fault+0x206/0x3c0 arch/x86/kvm/mmu/mmu.c:5092
 handle_ept_misconfig+0x96/0x150 arch/x86/kvm/vmx/vmx.c:5373
 vmx_handle_exit+0x2fd/0x7e0 arch/x86/kvm/vmx/vmx.c:6066
 vcpu_enter_guest+0x1978/0x2390 arch/x86/kvm/x86.c:8987
 vcpu_run+0x26e/0x730 arch/x86/kvm/x86.c:9052
 kvm_arch_vcpu_ioctl_run+0x362/0x660 arch/x86/kvm/x86.c:9269
 kvm_vcpu_ioctl+0x562/0x8f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3234
 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: 19310 Comm: syz-executor.1 Not tainted 5.10.0-rc1-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
2020/10/28 20:03 upstream ed8780e3f2ec f24824d3 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.