From: Isaku Yamahata <isaku.yamahata@gmail.com>
To: Chao Gao <chao.gao@intel.com>
Cc: isaku.yamahata@intel.com, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org, isaku.yamahata@gmail.com,
Paolo Bonzini <pbonzini@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Kai Huang <kai.huang@intel.com>, Will Deacon <will@kernel.org>
Subject: Re: [RFC PATCH 12/18] KVM: Do processor compatibility check on cpu online and resume
Date: Tue, 23 Aug 2022 01:08:31 -0700 [thread overview]
Message-ID: <20220823080831.GE2147148@ls.amr.corp.intel.com> (raw)
In-Reply-To: <YwSGsbpuJ5cdNmDG@gao-cwp>
On Tue, Aug 23, 2022 at 03:50:09PM +0800,
Chao Gao <chao.gao@intel.com> wrote:
> >diff --git a/virt/kvm/kvm_arch.c b/virt/kvm/kvm_arch.c
> >index 2ed8de0591c9..20971f43df95 100644
> >--- a/virt/kvm/kvm_arch.c
> >+++ b/virt/kvm/kvm_arch.c
> >@@ -99,9 +99,15 @@ __weak int kvm_arch_del_vm(int usage_count)
> >
> > __weak int kvm_arch_online_cpu(unsigned int cpu, int usage_count)
> > {
> >- if (usage_count)
> >- return __hardware_enable();
> >- return 0;
> >+ int r;
> >+
> >+ if (!usage_count)
> >+ return 0;
> >+
> >+ r = kvm_arch_check_processor_compat();
> >+ if (r)
> >+ return r;
>
> I think kvm_arch_check_processor_compat() should be called even when
> usage_count is 0. Otherwise, compatibility checks may be missing on some
> CPUs if no VM is running when those CPUs becomes online.
Oh, right. Compatibility check should be done unconditionally.
--
Isaku Yamahata <isaku.yamahata@gmail.com>
next prev parent reply other threads:[~2022-08-23 8:13 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-08-20 6:00 [RFC PATCH 00/18] KVM hardware enable/disable reorganize isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 01/18] KVM: x86: Drop kvm_user_return_msr_cpu_online() isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 02/18] KVM: x86: Use this_cpu_ptr() instead of per_cpu_ptr(smp_processor_id()) isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 03/18] KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock isaku.yamahata
2022-08-23 2:26 ` Chao Gao
2022-08-23 8:40 ` Isaku Yamahata
2022-08-20 6:00 ` [RFC PATCH 04/18] KVM: Add arch hooks for PM events with empty stub isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 05/18] KVM: x86: Move TSC fixup logic to KVM arch resume callback isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 06/18] KVM: Add arch hook when VM is added/deleted isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 07/18] KVM: Move out KVM arch PM hooks and hardware enable/disable logic isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 08/18] KVM: kvm_arch.c: Remove _nolock post fix isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 09/18] KVM: kvm_arch.c: Remove a global variable, hardware_enable_failed isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 10/18] KVM: x86: Move check_processor_compatibility from init ops to runtime ops isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 11/18] Partially revert "KVM: Pass kvm_init()'s opaque param to additional arch funcs" isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 12/18] KVM: Do processor compatibility check on cpu online and resume isaku.yamahata
2022-08-23 7:50 ` Chao Gao
2022-08-23 8:08 ` Isaku Yamahata [this message]
2022-08-20 6:00 ` [RFC PATCH 13/18] KVM: x86: Duplicate arch callbacks related to pm events isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 14/18] KVM: Eliminate kvm_arch_post_init_vm() isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 15/18] KVM: x86: Delete kvm_arch_hardware_enable/disable() isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 16/18] KVM: Add config to not compile kvm_arch.c isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 17/18] KVM: x86: Remove cpus_hardware_enabled and related sanity check isaku.yamahata
2022-08-20 6:00 ` [RFC PATCH 18/18] KVM: " isaku.yamahata
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