From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: Lenny Szubowicz <lszubowi@redhat.com>
Cc: pbonzini@redhat.com, seanjc@google.com, wanpengli@tencent.com,
jmattson@google.com, joro@8bytes.org, tglx@linutronix.de,
mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/kvmclock: Stop kvmclocks for hibernate restore
Date: Fri, 26 Mar 2021 14:01:35 +0100 [thread overview]
Message-ID: <87eeg2cbm8.fsf@vitty.brq.redhat.com> (raw)
In-Reply-To: <87h7kyccpu.fsf@vitty.brq.redhat.com>
Vitaly Kuznetsov <vkuznets@redhat.com> writes:
..
> (this is with your v2 included). There's nothing about CPU0 for
> e.g. async PF + timestamps are really interesting. Seems we have issues
> to fix) I'm playing with it right now.
What if we do the following (instead of your patch):
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 78bb0fae3982..c32392d6329d 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -26,6 +26,7 @@
#include <linux/kprobes.h>
#include <linux/nmi.h>
#include <linux/swait.h>
+#include <linux/syscore_ops.h>
#include <asm/timer.h>
#include <asm/cpu.h>
#include <asm/traps.h>
@@ -598,17 +599,21 @@ static void kvm_guest_cpu_offline(void)
static int kvm_cpu_online(unsigned int cpu)
{
- local_irq_disable();
+ unsigned long flags;
+
+ local_irq_save(flags);
kvm_guest_cpu_init();
- local_irq_enable();
+ local_irq_restore(flags);
return 0;
}
static int kvm_cpu_down_prepare(unsigned int cpu)
{
- local_irq_disable();
+ unsigned long flags;
+
+ local_irq_save(flags);
kvm_guest_cpu_offline();
- local_irq_enable();
+ local_irq_restore(flags);
return 0;
}
#endif
@@ -639,6 +644,23 @@ static void kvm_flush_tlb_others(const struct cpumask *cpumask,
native_flush_tlb_others(flushmask, info);
}
+static int kvm_suspend(void)
+{
+ kvm_guest_cpu_offline();
+
+ return 0;
+}
+
+static void kvm_resume(void)
+{
+ kvm_cpu_online(raw_smp_processor_id());
+}
+
+static struct syscore_ops kvm_syscore_ops = {
+ .suspend = kvm_suspend,
+ .resume = kvm_resume,
+};
+
static void __init kvm_guest_init(void)
{
int i;
@@ -681,6 +703,8 @@ static void __init kvm_guest_init(void)
kvm_guest_cpu_init();
#endif
+ register_syscore_ops(&kvm_syscore_ops);
+
/*
* Hard lockup detection is enabled by default. Disable it, as guests
* can get false positives too easily, for example if the host is
--
2.30.2
This seems to work fine (according to the log, I haven't checked yet
that PV features are actually working):
[ 20.678081] PM: hibernation: Creating image:
[ 20.689925] PM: hibernation: Need to copy 82048 pages
[ 2.302411] kvm-clock: cpu 0, msr 2c201001, primary cpu clock, resume
[ 2.302487] PM: Restoring platform NVS memory
[ 2.302498] kvm-guest: KVM setup async PF for cpu 0
[ 2.302502] kvm-guest: stealtime: cpu 0, msr 3ec2c080
[ 2.304754] Enabling non-boot CPUs ...
[ 2.304823] x86: Booting SMP configuration:
[ 2.304824] smpboot: Booting Node 0 Processor 1 APIC 0x1
[ 2.304952] kvm-clock: cpu 1, msr 2c201041, secondary cpu clock
[ 2.305400] kvm-guest: KVM setup async PF for cpu 1
[ 2.305405] kvm-guest: stealtime: cpu 1, msr 3ecac080
[ 2.305786] CPU1 is up
[ 2.305818] smpboot: Booting Node 0 Processor 2 APIC 0x2
[ 2.305920] kvm-clock: cpu 2, msr 2c201081, secondary cpu clock
[ 2.306325] kvm-guest: KVM setup async PF for cpu 2
[ 2.306330] kvm-guest: stealtime: cpu 2, msr 3ed2c080
[ 2.306599] CPU2 is up
[ 2.306627] smpboot: Booting Node 0 Processor 3 APIC 0x3
[ 2.306729] kvm-clock: cpu 3, msr 2c2010c1, secondary cpu clock
[ 2.307092] kvm-guest: KVM setup async PF for cpu 3
[ 2.307097] kvm-guest: stealtime: cpu 3, msr 3edac080
[ 2.307383] CPU3 is up
[ 2.307560] ACPI: Waking up from system sleep state S4
[ 2.318778] sd 0:0:0:0: [sda] Starting disk
[ 2.342335] OOM killer enabled.
[ 2.342817] Restarting tasks ... done.
[ 2.346209] PM: hibernation: hibernation exit
--
Vitaly
next prev parent reply other threads:[~2021-03-26 13:02 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-11 13:28 [PATCH] x86/kvmclock: Stop kvmclocks for hibernate restore Lenny Szubowicz
2021-03-17 13:30 ` Vitaly Kuznetsov
2021-03-26 2:26 ` Lenny Szubowicz
2021-03-26 10:57 ` Vitaly Kuznetsov
2021-03-26 12:37 ` Vitaly Kuznetsov
2021-03-26 13:01 ` Vitaly Kuznetsov [this message]
2021-03-26 17:14 ` Lenny Szubowicz
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