KCSAN: data-race in direct_page_fault / kvm_mmu_notifier_invalidate_range_end (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3bb61aa6 Merge tag 'arm64-fixes' of git://git.kernel.org/p..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17ae784b500000
kernel config: https://syzkaller.appspot.com/x/.config?x=c949fed53798f819
dashboard link: https://syzkaller.appspot.com/bug?extid=4f34b53424bc41bb9ed0
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [k...@vger.kernel.org linux-...@vger.kernel.org pbon...@redhat.com]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4f34b5...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in direct_page_fault / kvm_mmu_notifier_invalidate_range_end

read-write to 0xffffc900065461b0 of 8 bytes by task 18753 on cpu 1:
kvm_mmu_notifier_invalidate_range_end+0x2e/0x90 arch/x86/kvm/../../../virt/kvm/kvm_main.c:507
mn_hlist_invalidate_end mm/mmu_notifier.c:560 [inline]
__mmu_notifier_invalidate_range_end+0x18e/0x210 mm/mmu_notifier.c:580
mmu_notifier_invalidate_range_end include/linux/mmu_notifier.h:479 [inline]
change_pmd_range mm/mprotect.c:277 [inline]
change_pud_range mm/mprotect.c:297 [inline]
change_p4d_range mm/mprotect.c:317 [inline]
change_protection_range mm/mprotect.c:342 [inline]
change_protection+0x103e/0x12b0 mm/mprotect.c:365
mprotect_fixup+0x37a/0x580 mm/mprotect.c:487
do_mprotect_pkey+0x4c9/0x600 mm/mprotect.c:619
__do_sys_mprotect mm/mprotect.c:644 [inline]
__se_sys_mprotect mm/mprotect.c:641 [inline]
__x64_sys_mprotect+0x44/0x50 mm/mprotect.c:641
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffc900065461b0 of 8 bytes by task 18755 on cpu 0:
direct_page_fault+0x1c5/0x770 arch/x86/kvm/mmu/mmu.c:3702
kvm_tdp_page_fault+0x92/0xa0 arch/x86/kvm/mmu/mmu.c:3790
kvm_mmu_do_page_fault arch/x86/kvm/mmu.h:112 [inline]
kvm_mmu_page_fault+0xca/0x3c0 arch/x86/kvm/mmu/mmu.c:5059
handle_ept_violation+0x277/0x350 arch/x86/kvm/vmx/vmx.c:5357
vmx_handle_exit+0x2fd/0x7e0 arch/x86/kvm/vmx/vmx.c:6068
vcpu_enter_guest+0x199b/0x23b0 arch/x86/kvm/x86.c:9027
vcpu_run+0x24e/0x690 arch/x86/kvm/x86.c:9092
kvm_arch_vcpu_ioctl_run+0x362/0x660 arch/x86/kvm/x86.c:9309
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: 0 PID: 18755 Comm: syz-executor.0 Not tainted 5.10.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.