diff mbox series

[v2,06/10] KVM, x86: add architectural support code for #VE

Message ID 20240416201935.3525739-7-pbonzini@redhat.com (mailing list archive)
State New, archived
Headers show
Series KVM: MMU changes for confidential computing | expand

Commit Message

Paolo Bonzini April 16, 2024, 8:19 p.m. UTC
Dump the contents of the #VE info data structure and assert that #VE does
not happen, but do not yet do anything with it.

No functional change intended, separated for clarity only.

Extracted from a patch by Isaku Yamahata <isaku.yamahata@intel.com>.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/vmx.h | 12 ++++++++++++
 arch/x86/kvm/vmx/vmx.c     | 12 ++++++++++++
 2 files changed, 24 insertions(+)

Comments

Sean Christopherson April 17, 2024, 10:55 p.m. UTC | #1
KVM: x86:

On Tue, Apr 16, 2024, Paolo Bonzini wrote:
> Dump the contents of the #VE info data structure and assert that #VE does
> not happen, but do not yet do anything with it.
> 
> No functional change intended, separated for clarity only.
> 
> Extracted from a patch by Isaku Yamahata <isaku.yamahata@intel.com>.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

...

> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index 6780313914f8..2c746318c6c3 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -6408,6 +6408,18 @@ void dump_vmcs(struct kvm_vcpu *vcpu)
>  	if (secondary_exec_control & SECONDARY_EXEC_ENABLE_VPID)
>  		pr_err("Virtual processor ID = 0x%04x\n",
>  		       vmcs_read16(VIRTUAL_PROCESSOR_ID));
> +	if (secondary_exec_control & SECONDARY_EXEC_EPT_VIOLATION_VE) {
> +		struct vmx_ve_information *ve_info;
> +
> +		pr_err("VE info address = 0x%016llx\n",
> +		       vmcs_read64(VE_INFORMATION_ADDRESS));
> +		ve_info = __va(vmcs_read64(VE_INFORMATION_ADDRESS));

As I pointed out in v1[*], pulling the PA->VA from the VMCS is a bad idea.  Just
use vmx->ve_info.

 : If KVM is dumping the VMCS, then something has gone wrong, possible in
 : hardware or ucode. Derefencing an address from the VMCS, which could very
 : well be corrupted, is a terrible idea.  This could easily escalate from a
 : dead VM into a dead host. 

[*] https://lore.kernel.org/all/Zd6Sy_PujXJVji0n@google.com
diff mbox series

Patch

diff --git a/arch/x86/include/asm/vmx.h b/arch/x86/include/asm/vmx.h
index ac6da0a5f5e6..d77a31039f24 100644
--- a/arch/x86/include/asm/vmx.h
+++ b/arch/x86/include/asm/vmx.h
@@ -71,6 +71,7 @@ 
 #define SECONDARY_EXEC_ENCLS_EXITING		VMCS_CONTROL_BIT(ENCLS_EXITING)
 #define SECONDARY_EXEC_RDSEED_EXITING		VMCS_CONTROL_BIT(RDSEED_EXITING)
 #define SECONDARY_EXEC_ENABLE_PML               VMCS_CONTROL_BIT(PAGE_MOD_LOGGING)
+#define SECONDARY_EXEC_EPT_VIOLATION_VE		VMCS_CONTROL_BIT(EPT_VIOLATION_VE)
 #define SECONDARY_EXEC_PT_CONCEAL_VMX		VMCS_CONTROL_BIT(PT_CONCEAL_VMX)
 #define SECONDARY_EXEC_ENABLE_XSAVES		VMCS_CONTROL_BIT(XSAVES)
 #define SECONDARY_EXEC_MODE_BASED_EPT_EXEC	VMCS_CONTROL_BIT(MODE_BASED_EPT_EXEC)
@@ -226,6 +227,8 @@  enum vmcs_field {
 	VMREAD_BITMAP_HIGH              = 0x00002027,
 	VMWRITE_BITMAP                  = 0x00002028,
 	VMWRITE_BITMAP_HIGH             = 0x00002029,
+	VE_INFORMATION_ADDRESS		= 0x0000202A,
+	VE_INFORMATION_ADDRESS_HIGH	= 0x0000202B,
 	XSS_EXIT_BITMAP                 = 0x0000202C,
 	XSS_EXIT_BITMAP_HIGH            = 0x0000202D,
 	ENCLS_EXITING_BITMAP		= 0x0000202E,
@@ -631,4 +634,13 @@  enum vmx_l1d_flush_state {
 
 extern enum vmx_l1d_flush_state l1tf_vmx_mitigation;
 
+struct vmx_ve_information {
+	u32 exit_reason;
+	u32 delivery;
+	u64 exit_qualification;
+	u64 guest_linear_address;
+	u64 guest_physical_address;
+	u16 eptp_index;
+};
+
 #endif
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6780313914f8..2c746318c6c3 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6408,6 +6408,18 @@  void dump_vmcs(struct kvm_vcpu *vcpu)
 	if (secondary_exec_control & SECONDARY_EXEC_ENABLE_VPID)
 		pr_err("Virtual processor ID = 0x%04x\n",
 		       vmcs_read16(VIRTUAL_PROCESSOR_ID));
+	if (secondary_exec_control & SECONDARY_EXEC_EPT_VIOLATION_VE) {
+		struct vmx_ve_information *ve_info;
+
+		pr_err("VE info address = 0x%016llx\n",
+		       vmcs_read64(VE_INFORMATION_ADDRESS));
+		ve_info = __va(vmcs_read64(VE_INFORMATION_ADDRESS));
+		pr_err("ve_info: 0x%08x 0x%08x 0x%016llx 0x%016llx 0x%016llx 0x%04x\n",
+		       ve_info->exit_reason, ve_info->delivery,
+		       ve_info->exit_qualification,
+		       ve_info->guest_linear_address,
+		       ve_info->guest_physical_address, ve_info->eptp_index);
+	}
 }
 
 /*