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KCSAN: data-race in install_new_memslots / vcpu_is_mmio_gpa.part.0 (2)

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kvm
[Documentation on labels]
First crash: 1630d, last: 1442d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in install_new_memslots / vcpu_is_mmio_gpa.part.0 kvm 3 1655d 1656d 0/26 closed as invalid on 2019/11/19 13:44

Sample crash report:
==================================================================
BUG: KCSAN: data-race in install_new_memslots / vcpu_is_mmio_gpa.part.0

write to 0xffff88804796b000 of 8 bytes by task 17961 on cpu 1:
 install_new_memslots+0xe9/0x130 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1077
 kvm_set_memslot+0x800/0xb70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1153
 __kvm_set_memory_region+0x91c/0xc20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1300
 kvm_set_memory_region+0x31/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1321
 kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1333 [inline]
 kvm_vm_ioctl+0x662/0x18b0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3604
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x101/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88804796b000 of 8 bytes by task 17958 on cpu 0:
 vcpu_match_mmio_gen arch/x86/kvm/x86.h:183 [inline]
 vcpu_match_mmio_gpa arch/x86/kvm/x86.h:211 [inline]
 vcpu_is_mmio_gpa.part.0+0x8e/0x220 arch/x86/kvm/x86.c:5577
 vcpu_is_mmio_gpa arch/x86/kvm/x86.c:5574 [inline]
 vcpu_mmio_gva_to_gpa arch/x86/kvm/x86.c:5611 [inline]
 emulator_read_write_onepage+0x29a/0x740 arch/x86/kvm/x86.c:5722
 emulator_read_write.isra.0+0x15b/0x300 arch/x86/kvm/x86.c:5782
 emulator_read_emulated+0x4a/0x60 arch/x86/kvm/x86.c:5809
 read_emulated arch/x86/kvm/emulate.c:1457 [inline]
 segmented_read+0x172/0x220 arch/x86/kvm/emulate.c:1481
 x86_emulate_insn+0x9c9/0x2840 arch/x86/kvm/emulate.c:5621
 x86_emulate_instruction+0x702/0x11d0 arch/x86/kvm/x86.c:6867
 kvm_mmu_page_fault+0x1c7/0xac0 arch/x86/kvm/mmu/mmu.c:5495
 handle_ept_misconfig+0xbc/0x240 arch/x86/kvm/vmx/vmx.c:5214
 vmx_handle_exit+0x1de/0xfe0 arch/x86/kvm/vmx/vmx.c:5980
 vcpu_enter_guest+0xc00/0x3740 arch/x86/kvm/x86.c:8481
 vcpu_run arch/x86/kvm/x86.c:8544 [inline]
 kvm_arch_vcpu_ioctl_run+0x281/0xd60 arch/x86/kvm/x86.c:8766
 kvm_vcpu_ioctl+0x70b/0x9d0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3138
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x101/0x150 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17958 Comm: syz-executor.4 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/05/29 16:29 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 bed08304 .config console log report ci2-upstream-kcsan-gce
2020/05/05 07:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 9941337c .config console log report ci2-upstream-kcsan-gce
2020/04/15 23:58 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 3f3c5574 .config console log report ci2-upstream-kcsan-gce
2020/02/25 10:26 https://github.com/google/ktsan.git kcsan 766d004d1b85 59b57593 .config console log report ci2-upstream-kcsan-gce
2020/01/08 07:02 https://github.com/google/ktsan.git kcsan 245a43005292 6738e0b3 .config console log report ci2-upstream-kcsan-gce
2019/11/23 10:48 https://github.com/google/ktsan.git kcsan 5863cc791e4c 598ca6c8 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.