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dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54514 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLWa9-0003T8-Lc for qemu-devel@archiver.kernel.org; Thu, 24 Sep 2020 15:07:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45490) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kLWV1-0007wF-2j for qemu-devel@nongnu.org; Thu, 24 Sep 2020 15:01:47 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:47755) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kLWUy-0003W2-4L for qemu-devel@nongnu.org; Thu, 24 Sep 2020 15:01:46 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1600974102; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; 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auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=216.205.24.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/22 23:02:20 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.199, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Antoine Damhet , Paolo Bonzini , Marcelo Tosatti , qemu-devel@nongnu.org, Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Vitaly Kuznetsov (vkuznets@redhat.com) wrote: > QEMU's kvmclock device is only created when KVM PV feature bits for > kvmclock (KVM_FEATURE_CLOCKSOURCE/KVM_FEATURE_CLOCKSOURCE2) are > exposed to the guest. With 'kvm=off' cpu flag the device is not > created and we don't call KVM_GET_CLOCK/KVM_SET_CLOCK upon migration. > It was reported that without these call at least Hyper-V TSC page > clocksouce (which can be enabled independently) gets broken after > migration. > > Switch to creating kvmclock QEMU device unconditionally, it seems > to always make sense to call KVM_GET_CLOCK/KVM_SET_CLOCK on migration. > Use KVM_CAP_ADJUST_CLOCK check instead of CPUID feature bits. > > Reported-by: Antoine Damhet > Suggested-by: Paolo Bonzini > Signed-off-by: Vitaly Kuznetsov > --- > hw/i386/kvm/clock.c | 7 +++++-- > hw/i386/microvm.c | 2 +- > hw/i386/pc.c | 1 + > hw/i386/pc_piix.c | 7 +++++-- > hw/i386/pc_q35.c | 5 ++++- > include/hw/i386/pc.h | 3 +++ > include/hw/kvm/clock.h | 4 ++-- > target/i386/kvm.c | 5 +++++ > target/i386/kvm_i386.h | 1 + > 9 files changed, 27 insertions(+), 8 deletions(-) > > diff --git a/hw/i386/kvm/clock.c b/hw/i386/kvm/clock.c > index 64283358f91d..30cf53393ee1 100644 > --- a/hw/i386/kvm/clock.c > +++ b/hw/i386/kvm/clock.c > @@ -328,11 +328,14 @@ static const TypeInfo kvmclock_info = { > }; > > /* Note: Must be called after VCPU initialization. */ > -void kvmclock_create(void) > +void kvmclock_create(bool create_always) > { > X86CPU *cpu = X86_CPU(first_cpu); > > - if (kvm_enabled() && > + if (!kvm_enabled() || !kvm_has_adjust_clock()) > + return; > + > + if (create_always || > cpu->env.features[FEAT_KVM] & ((1ULL << KVM_FEATURE_CLOCKSOURCE) | > (1ULL << KVM_FEATURE_CLOCKSOURCE2))) { > sysbus_create_simple(TYPE_KVM_CLOCK, -1, NULL); > diff --git a/hw/i386/microvm.c b/hw/i386/microvm.c > index 81d0888930d1..fd0b84109154 100644 > --- a/hw/i386/microvm.c > +++ b/hw/i386/microvm.c > @@ -119,7 +119,7 @@ static void microvm_devices_init(MicrovmMachineState *mms) > > ioapic_init_gsi(gsi_state, "machine"); > > - kvmclock_create(); > + kvmclock_create(true); > > for (i = 0; i < VIRTIO_NUM_TRANSPORTS; i++) { > sysbus_create_simple("virtio-mmio", > diff --git a/hw/i386/pc.c b/hw/i386/pc.c > index d11daacc23cf..0e036ef9c15f 100644 > --- a/hw/i386/pc.c > +++ b/hw/i386/pc.c > @@ -1956,6 +1956,7 @@ static void pc_machine_class_init(ObjectClass *oc, void *data) > pcmc->acpi_data_size = 0x20000 + 0x8000; > pcmc->linuxboot_dma_enabled = true; > pcmc->pvh_enabled = true; > + pcmc->kvmclock_create_always = true; > assert(!mc->get_hotplug_handler); > mc->get_hotplug_handler = pc_get_hotplug_handler; > mc->hotplug_allowed = pc_hotplug_allowed; > diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c > index 32b1453e6a82..1a68338c737b 100644 > --- a/hw/i386/pc_piix.c > +++ b/hw/i386/pc_piix.c > @@ -158,8 +158,8 @@ static void pc_init1(MachineState *machine, > > x86_cpus_init(x86ms, pcmc->default_cpu_version); > > - if (kvm_enabled() && pcmc->kvmclock_enabled) { > - kvmclock_create(); > + if (pcmc->kvmclock_enabled) { > + kvmclock_create(pcmc->kvmclock_create_always); > } > > if (pcmc->pci_enabled) { > @@ -440,11 +440,14 @@ DEFINE_I440FX_MACHINE(v5_2, "pc-i440fx-5.2", NULL, > > static void pc_i440fx_5_1_machine_options(MachineClass *m) > { > + PCMachineClass *pcmc = PC_MACHINE_CLASS(m); > + > pc_i440fx_5_2_machine_options(m); > m->alias = NULL; > m->is_default = false; > compat_props_add(m->compat_props, hw_compat_5_1, hw_compat_5_1_len); > compat_props_add(m->compat_props, pc_compat_5_1, pc_compat_5_1_len); > + pcmc->kvmclock_create_always = false; Thanks; yes that should keep backwards migration happy. Dave > } > > DEFINE_I440FX_MACHINE(v5_1, "pc-i440fx-5.1", NULL, > diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c > index 0cb9c18cd44d..0dd59bd765b1 100644 > --- a/hw/i386/pc_q35.c > +++ b/hw/i386/pc_q35.c > @@ -185,7 +185,7 @@ static void pc_q35_init(MachineState *machine) > > x86_cpus_init(x86ms, pcmc->default_cpu_version); > > - kvmclock_create(); > + kvmclock_create(pcmc->kvmclock_create_always); > > /* pci enabled */ > if (pcmc->pci_enabled) { > @@ -366,10 +366,13 @@ DEFINE_Q35_MACHINE(v5_2, "pc-q35-5.2", NULL, > > static void pc_q35_5_1_machine_options(MachineClass *m) > { > + PCMachineClass *pcmc = PC_MACHINE_CLASS(m); > + > pc_q35_5_2_machine_options(m); > m->alias = NULL; > compat_props_add(m->compat_props, hw_compat_5_1, hw_compat_5_1_len); > compat_props_add(m->compat_props, pc_compat_5_1, pc_compat_5_1_len); > + pcmc->kvmclock_create_always = false; > } > > DEFINE_Q35_MACHINE(v5_1, "pc-q35-5.1", NULL, > diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h > index fe52e165b27c..6b22671434b9 100644 > --- a/include/hw/i386/pc.h > +++ b/include/hw/i386/pc.h > @@ -118,6 +118,9 @@ typedef struct PCMachineClass { > > /* use PVH to load kernels that support this feature */ > bool pvh_enabled; > + > + /* create kvmclock device even when KVM PV features are not exposed */ > + bool kvmclock_create_always; > } PCMachineClass; > > #define TYPE_PC_MACHINE "generic-pc-machine" > diff --git a/include/hw/kvm/clock.h b/include/hw/kvm/clock.h > index 81c66b230207..7994071c4fee 100644 > --- a/include/hw/kvm/clock.h > +++ b/include/hw/kvm/clock.h > @@ -15,11 +15,11 @@ > > #ifdef CONFIG_KVM > > -void kvmclock_create(void); > +void kvmclock_create(bool create_always); > > #else /* CONFIG_KVM */ > > -static inline void kvmclock_create(void) > +static inline void kvmclock_create(bool create_always) > { > } > > diff --git a/target/i386/kvm.c b/target/i386/kvm.c > index 4a8b3a41c1bc..20b31b65307b 100644 > --- a/target/i386/kvm.c > +++ b/target/i386/kvm.c > @@ -143,6 +143,11 @@ bool kvm_has_adjust_clock_stable(void) > return (ret == KVM_CLOCK_TSC_STABLE); > } > > +bool kvm_has_adjust_clock(void) > +{ > + return kvm_check_extension(kvm_state, KVM_CAP_ADJUST_CLOCK); > +} > + > bool kvm_has_exception_payload(void) > { > return has_exception_payload; > diff --git a/target/i386/kvm_i386.h b/target/i386/kvm_i386.h > index 064b8798a26c..0fce4e51d2d6 100644 > --- a/target/i386/kvm_i386.h > +++ b/target/i386/kvm_i386.h > @@ -34,6 +34,7 @@ > > bool kvm_allows_irq0_override(void); > bool kvm_has_smm(void); > +bool kvm_has_adjust_clock(void); > bool kvm_has_adjust_clock_stable(void); > bool kvm_has_exception_payload(void); > void kvm_synchronize_all_tsc(void); > -- > 2.25.4 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK