KCSAN: data-race in handle_mmio_page_fault / kvm_set

KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot (4)
Status: auto-closed as invalid on 2021/04/27 19:30
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 181d, last: 181d

similar bugs (3):
Kernel	Title	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot (3)	2	220d	255d	0/22	auto-closed as invalid on 2021/03/19 14:24
upstream	KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot	3	351d	363d	0/22	auto-closed as invalid on 2020/11/08 13:13
upstream	KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot (2)	1	297d	287d	0/22	auto-closed as invalid on 2021/01/02 05:15

Sample crash report:

==================================================================
BUG: KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot

write to 0xffff88801bf80000 of 8 bytes by task 12292 on cpu 1:
 install_new_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:1169 [inline]
 kvm_set_memslot+0x958/0xa10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1245
 __kvm_set_memory_region+0x794/0x930 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1398
 kvm_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1419 [inline]
 kvm_vm_ioctl_set_memory_region arch/x86/kvm/../../../virt/kvm/kvm_main.c:1431 [inline]
 kvm_vm_ioctl+0xad0/0x1c50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3858
 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+0x44/0xae

read to 0xffff88801bf80000 of 8 bytes by task 12287 on cpu 0:
 mmio_info_in_cache arch/x86/kvm/mmu/mmu.c:3472 [inline]
 handle_mmio_page_fault+0xa2/0x960 arch/x86/kvm/mmu/mmu.c:3572
 kvm_mmu_page_fault+0x348/0x3c0 arch/x86/kvm/mmu/mmu.c:5015
 handle_ept_misconfig+0x96/0x150 arch/x86/kvm/vmx/vmx.c:5398
 __vmx_handle_exit+0x35b/0x850 arch/x86/kvm/vmx/vmx.c:6090
 vmx_handle_exit+0x1a/0xd0 arch/x86/kvm/vmx/vmx.c:6107
 vcpu_enter_guest+0x1a3e/0x2650 arch/x86/kvm/x86.c:9216
 vcpu_run+0x24f/0x6a0 arch/x86/kvm/x86.c:9282
 kvm_arch_vcpu_ioctl_run+0x476/0x860 arch/x86/kvm/x86.c:9510
 kvm_vcpu_ioctl+0x562/0x8f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3316
 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+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12287 Comm: syz-executor.1 Tainted: G        W         5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Title
ci2-upstream-kcsan-gce	2021/03/23 19:27	upstream	7acac4b3196c	e613994b	.config	log	report			info	KCSAN: data-race in handle_mmio_page_fault / kvm_set_memslot