| Message ID | 1644920142-81249-1-git-send-email-wanpengli@tencent.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: Fix lockdep false negative during host resume | expand |
On Tue, Feb 15, 2022, Wanpeng Li wrote: > From: Wanpeng Li <wanpengli@tencent.com> > > 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. > Fixes: 2eb06c306a57 ("KVM: Fix spinlock taken warning during host resume") > Signed-off-by: Wanpeng Li <wanpengli@tencent.com> > --- > virt/kvm/kvm_main.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 83c57bcc6eb6..3f861f33bfe0 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -5528,7 +5528,7 @@ static void kvm_resume(void) > { > if (kvm_usage_count) { > #ifdef CONFIG_LOCKDEP The #ifdef can be dropped, it was added only to omit the WARN_ON. With that, Reviewed-by: Sean Christopherson <seanjc@google.com> > - WARN_ON(lockdep_is_held(&kvm_count_lock)); > + lockdep_assert_not_held(&kvm_count_lock); > #endif > hardware_enable_nolock(NULL); > } > -- > 2.25.1 >
On 2/15/22 17:26, Sean Christopherson wrote:
> Reviewed-by: Sean Christopherson<seanjc@google.com>
Queued with the #ifdef removed, thanks.
Paolo
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 83c57bcc6eb6..3f861f33bfe0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -5528,7 +5528,7 @@ static void kvm_resume(void) { if (kvm_usage_count) { #ifdef CONFIG_LOCKDEP - WARN_ON(lockdep_is_held(&kvm_count_lock)); + lockdep_assert_not_held(&kvm_count_lock); #endif hardware_enable_nolock(NULL); }