From: He Zhe <zhe.he@xxxxxxxxxxxxx> apic->lapic_timer.timer was initialized with HRTIMER_MODE_ABS_HARD but started later with HRTIMER_MODE_ABS, which may cause the following warning in PREEMPT_RT kernel. WARNING: CPU: 1 PID: 2957 at kernel/time/hrtimer.c:1129 hrtimer_start_range_ns+0x348/0x3f0 CPU: 1 PID: 2957 Comm: qemu-system-x86 Not tainted 5.4.23-rt11 #1 Hardware name: Supermicro SYS-E300-9A-8C/A2SDi-8C-HLN4F, BIOS 1.1a 09/18/2018 RIP: 0010:hrtimer_start_range_ns+0x348/0x3f0 Code: 4d b8 0f 94 c1 0f b6 c9 e8 35 f1 ff ff 4c 8b 45 b0 e9 3b fd ff ff e8 d7 3f fa ff 48 98 4c 03 34 c5 a0 26 bf 93 e9 a1 fd ff ff <0f> 0b e9 fd fc ff ff 65 8b 05 fa b7 90 6d 89 c0 48 0f a3 05 60 91 RSP: 0018:ffffbc60026ffaf8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff9d81657d4110 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000006cc7987bcf RDI: ffff9d81657d4110 RBP: ffffbc60026ffb58 R08: 0000000000000001 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000000 R12: 0000006cc7987bcf R13: 0000000000000000 R14: 0000006cc7987bcf R15: ffffbc60026d6a00 FS: 00007f401daed700(0000) GS:ffff9d81ffa40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000ffffffff CR3: 0000000fa7574000 CR4: 00000000003426e0 Call Trace: ? kvm_release_pfn_clean+0x22/0x60 [kvm] start_sw_timer+0x85/0x230 [kvm] ? vmx_vmexit+0x1b/0x30 [kvm_intel] kvm_lapic_switch_to_sw_timer+0x72/0x80 [kvm] vmx_pre_block+0x1cb/0x260 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_sync_pir_to_irr+0x9e/0x100 [kvm_intel] ? kvm_apic_has_interrupt+0x46/0x80 [kvm] kvm_arch_vcpu_ioctl_run+0x85b/0x1fa0 [kvm] ? _raw_spin_unlock_irqrestore+0x18/0x50 ? _copy_to_user+0x2c/0x30 kvm_vcpu_ioctl+0x235/0x660 [kvm] ? rt_spin_unlock+0x2c/0x50 do_vfs_ioctl+0x3e4/0x650 ? __fget+0x7a/0xa0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x4d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f4027cc54a7 Code: 00 00 90 48 8b 05 e9 59 0c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d b9 59 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007f401dae9858 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00005558bd029690 RCX: 00007f4027cc54a7 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 000000000000000d RBP: 00007f4028b72000 R08: 00005558bc829ad0 R09: 00000000ffffffff R10: 00005558bcf90ca0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00005558bce1c840 --[ end trace 0000000000000002 ]-- Signed-off-by: He Zhe <zhe.he@xxxxxxxxxxxxx> --- arch/x86/kvm/lapic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index e3099c6..929511e 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1715,7 +1715,7 @@ static void start_sw_period(struct kvm_lapic *apic) hrtimer_start(&apic->lapic_timer.timer, apic->lapic_timer.target_expiration, - HRTIMER_MODE_ABS); + HRTIMER_MODE_ABS_HARD); } bool kvm_lapic_hv_timer_in_use(struct kvm_vcpu *vcpu) -- 2.7.4