This is a note to let you know that I've just added the patch titled KVM: Fix lockdep false negative during host resume to the 5.16-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: kvm-fix-lockdep-false-negative-during-host-resume.patch and it can be found in the queue-5.16 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 25944e8c7591504c63cfdc267fbff345b019cfc0 Author: Wanpeng Li <wanpengli@xxxxxxxxxxx> Date: Tue Feb 15 02:15:42 2022 -0800 KVM: Fix lockdep false negative during host resume [ Upstream commit 4cb9a998b1ce25fad74a82f5a5c45a4ef40de337 ] I saw the below splatting after the host suspended and resumed. WARNING: CPU: 0 PID: 2943 at kvm/arch/x86/kvm/../../../virt/kvm/kvm_main.c:5531 kvm_resume+0x2c/0x30 [kvm] CPU: 0 PID: 2943 Comm: step_after_susp Tainted: G W IOE 5.17.0-rc3+ #4 RIP: 0010:kvm_resume+0x2c/0x30 [kvm] Call Trace: <TASK> syscore_resume+0x90/0x340 suspend_devices_and_enter+0xaee/0xe90 pm_suspend.cold+0x36b/0x3c2 state_store+0x82/0xf0 kernfs_fop_write_iter+0x1b6/0x260 new_sync_write+0x258/0x370 vfs_write+0x33f/0x510 ksys_write+0xc9/0x160 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae lockdep_is_held() can return -1 when lockdep is disabled which triggers this warning. Let's use lockdep_assert_not_held() which can detect incorrect calls while holding a lock and it also avoids false negatives when lockdep is disabled. Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx> Message-Id: <1644920142-81249-1-git-send-email-wanpengli@xxxxxxxxxxx> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 71ddc7a8bc30..6ae9e04d0585 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -5347,9 +5347,7 @@ static int kvm_suspend(void) static void kvm_resume(void) { if (kvm_usage_count) { -#ifdef CONFIG_LOCKDEP - WARN_ON(lockdep_is_held(&kvm_count_lock)); -#endif + lockdep_assert_not_held(&kvm_count_lock); hardware_enable_nolock(NULL); } }