[PATCH v4 09/26] KVM: Do processor compatibility check on resume

From: isaku.yamahata@intel.com
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	Paolo Bonzini <pbonzini@redhat.com>,
	Sean Christopherson <seanjc@google.com>,
	Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
	Yuan Yao <yuan.yao@linux.intel.com>
Cc: isaku.yamahata@intel.com, isaku.yamahata@gmail.com,
	Kai Huang <kai.huang@intel.com>, Chao Gao <chao.gao@intel.com>,
	Atish Patra <atishp@atishpatra.org>,
	Shaokun Zhang <zhangshaokun@hisilicon.com>,
	Qi Liu <liuqi115@huawei.com>, John Garry <john.garry@huawei.com>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Huang Ying <ying.huang@intel.com>,
	Huacai Chen <chenhuacai@kernel.org>
Subject: [PATCH v4 09/26] KVM: Do processor compatibility check on resume
Date: Thu,  8 Sep 2022 16:25:25 -0700	[thread overview]
Message-ID: <1c302387e21e689f103bf954f355cf49f73d1e82.1662679124.git.isaku.yamahata@intel.com> (raw)
In-Reply-To: <cover.1662679124.git.isaku.yamahata@intel.com>

From: Isaku Yamahata <isaku.yamahata@intel.com>

So far the processor compatibility check is not done on resume. It should
be done.  The resume is called for resuming from S3/S4.  CPUs can be
replaced or the kernel can resume from S4 on a different machine.  So
compatibility check is desirable.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
 virt/kvm/kvm_main.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0ac00c711384..fc55447c4dba 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5715,6 +5715,13 @@ static int kvm_suspend(void)
 
 static void kvm_resume(void)
 {
+	if (kvm_arch_check_processor_compat())
+		/*
+		 * No warning here because kvm_arch_check_processor_compat()
+		 * would have warned with more information.
+		 */
+		return; /* FIXME: disable KVM */
+
 	if (kvm_usage_count) {
 		lockdep_assert_not_held(&kvm_count_lock);
 		hardware_enable_nolock((void *)__func__);
-- 
2.25.1

