diff mbox series

[Part1,RFC,v4,23/36] KVM: x86: move lookup of indexed CPUID leafs to helper

Message ID 20210707181506.30489-24-brijesh.singh@amd.com
State New
Headers show
Series Add AMD Secure Nested Paging (SEV-SNP) Guest Support | expand

Commit Message

Brijesh Singh July 7, 2021, 6:14 p.m. UTC
From: Michael Roth <michael.roth@amd.com>

Determining which CPUID leafs have significant ECX/index values is
also needed by guest kernel code when doing SEV-SNP-validated CPUID
lookups. Move this to common code to keep future updates in sync.

Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 arch/x86/include/asm/cpuid-indexed.h | 26 ++++++++++++++++++++++++++
 arch/x86/kvm/cpuid.c                 | 17 ++---------------
 2 files changed, 28 insertions(+), 15 deletions(-)
 create mode 100644 arch/x86/include/asm/cpuid-indexed.h

Comments

Borislav Petkov Aug. 19, 2021, 10:07 a.m. UTC | #1
On Wed, Jul 07, 2021 at 01:14:53PM -0500, Brijesh Singh wrote:
> From: Michael Roth <michael.roth@amd.com>

> 

> Determining which CPUID leafs have significant ECX/index values is

> also needed by guest kernel code when doing SEV-SNP-validated CPUID

> lookups. Move this to common code to keep future updates in sync.

> 

> Signed-off-by: Michael Roth <michael.roth@amd.com>

> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>

> ---

>  arch/x86/include/asm/cpuid-indexed.h | 26 ++++++++++++++++++++++++++

>  arch/x86/kvm/cpuid.c                 | 17 ++---------------

>  2 files changed, 28 insertions(+), 15 deletions(-)

>  create mode 100644 arch/x86/include/asm/cpuid-indexed.h

> 

> diff --git a/arch/x86/include/asm/cpuid-indexed.h b/arch/x86/include/asm/cpuid-indexed.h

> new file mode 100644

> index 000000000000..f5ab746f5712

> --- /dev/null

> +++ b/arch/x86/include/asm/cpuid-indexed.h


Just call it arch/x86/include/asm/cpuid.h

And if you feel bored, you can move the cpuid* primitives from
asm/processor.h to it, in another patch so that processor.h gets
slimmer.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette
diff mbox series

Patch

diff --git a/arch/x86/include/asm/cpuid-indexed.h b/arch/x86/include/asm/cpuid-indexed.h
new file mode 100644
index 000000000000..f5ab746f5712
--- /dev/null
+++ b/arch/x86/include/asm/cpuid-indexed.h
@@ -0,0 +1,26 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_CPUID_INDEXED_H
+#define _ASM_X86_CPUID_INDEXED_H
+
+static __always_inline bool cpuid_function_is_indexed(u32 function)
+{
+	switch (function) {
+	case 4:
+	case 7:
+	case 0xb:
+	case 0xd:
+	case 0xf:
+	case 0x10:
+	case 0x12:
+	case 0x14:
+	case 0x17:
+	case 0x18:
+	case 0x1f:
+	case 0x8000001d:
+		return true;
+	}
+
+	return false;
+}
+
+#endif /* _ASM_X86_CPUID_INDEXED_H */
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index b4da665bb892..be6b226f50e4 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -19,6 +19,7 @@ 
 #include <asm/user.h>
 #include <asm/fpu/xstate.h>
 #include <asm/sgx.h>
+#include <asm/cpuid-indexed.h>
 #include "cpuid.h"
 #include "lapic.h"
 #include "mmu.h"
@@ -608,22 +609,8 @@  static struct kvm_cpuid_entry2 *do_host_cpuid(struct kvm_cpuid_array *array,
 	cpuid_count(entry->function, entry->index,
 		    &entry->eax, &entry->ebx, &entry->ecx, &entry->edx);
 
-	switch (function) {
-	case 4:
-	case 7:
-	case 0xb:
-	case 0xd:
-	case 0xf:
-	case 0x10:
-	case 0x12:
-	case 0x14:
-	case 0x17:
-	case 0x18:
-	case 0x1f:
-	case 0x8000001d:
+	if (cpuid_function_is_indexed(function))
 		entry->flags |= KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
-		break;
-	}
 
 	return entry;
 }