[tip: x86/urgent] x86/sev: Move GHCB MSR protocol and NAE definitions in a common header

From: tip-bot2 for Brijesh Singh
Date: Mon May 10 2021 - 04:43:14 EST


The following commit has been merged into the x86/urgent branch of tip:

Commit-ID: b81fc74d53d1248de6db3136dd6b29e5d5528021
Gitweb: https://git.kernel.org/tip/b81fc74d53d1248de6db3136dd6b29e5d5528021
Author: Brijesh Singh <brijesh.singh@xxxxxxx>
AuthorDate: Tue, 27 Apr 2021 06:16:35 -05:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Mon, 10 May 2021 07:46:39 +02:00

x86/sev: Move GHCB MSR protocol and NAE definitions in a common header

The guest and the hypervisor contain separate macros to get and set
the GHCB MSR protocol and NAE event fields. Consolidate the GHCB
protocol definitions and helper macros in one place.

Leave the supported protocol version define in separate files to keep
the guest and hypervisor flexibility to support different GHCB version
in the same release.

There is no functional change intended.

Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Acked-by: Joerg Roedel <jroedel@xxxxxxx>
Link: https://lkml.kernel.org/r/20210427111636.1207-3-brijesh.singh@xxxxxxx
---
arch/x86/include/asm/sev-common.h | 62 ++++++++++++++++++++++++++++++-
arch/x86/include/asm/sev.h | 30 ++-------------
arch/x86/kernel/sev-shared.c | 20 +++++-----
arch/x86/kvm/svm/svm.h | 38 +-----------------
4 files changed, 80 insertions(+), 70 deletions(-)
create mode 100644 arch/x86/include/asm/sev-common.h

diff --git a/arch/x86/include/asm/sev-common.h b/arch/x86/include/asm/sev-common.h
new file mode 100644
index 0000000..629c3df
--- /dev/null
+++ b/arch/x86/include/asm/sev-common.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AMD SEV header common between the guest and the hypervisor.
+ *
+ * Author: Brijesh Singh <brijesh.singh@xxxxxxx>
+ */
+
+#ifndef __ASM_X86_SEV_COMMON_H
+#define __ASM_X86_SEV_COMMON_H
+
+#define GHCB_MSR_INFO_POS 0
+#define GHCB_MSR_INFO_MASK (BIT_ULL(12) - 1)
+
+#define GHCB_MSR_SEV_INFO_RESP 0x001
+#define GHCB_MSR_SEV_INFO_REQ 0x002
+#define GHCB_MSR_VER_MAX_POS 48
+#define GHCB_MSR_VER_MAX_MASK 0xffff
+#define GHCB_MSR_VER_MIN_POS 32
+#define GHCB_MSR_VER_MIN_MASK 0xffff
+#define GHCB_MSR_CBIT_POS 24
+#define GHCB_MSR_CBIT_MASK 0xff
+#define GHCB_MSR_SEV_INFO(_max, _min, _cbit) \
+ ((((_max) & GHCB_MSR_VER_MAX_MASK) << GHCB_MSR_VER_MAX_POS) | \
+ (((_min) & GHCB_MSR_VER_MIN_MASK) << GHCB_MSR_VER_MIN_POS) | \
+ (((_cbit) & GHCB_MSR_CBIT_MASK) << GHCB_MSR_CBIT_POS) | \
+ GHCB_MSR_SEV_INFO_RESP)
+#define GHCB_MSR_INFO(v) ((v) & 0xfffUL)
+#define GHCB_MSR_PROTO_MAX(v) (((v) >> GHCB_MSR_VER_MAX_POS) & GHCB_MSR_VER_MAX_MASK)
+#define GHCB_MSR_PROTO_MIN(v) (((v) >> GHCB_MSR_VER_MIN_POS) & GHCB_MSR_VER_MIN_MASK)
+
+#define GHCB_MSR_CPUID_REQ 0x004
+#define GHCB_MSR_CPUID_RESP 0x005
+#define GHCB_MSR_CPUID_FUNC_POS 32
+#define GHCB_MSR_CPUID_FUNC_MASK 0xffffffff
+#define GHCB_MSR_CPUID_VALUE_POS 32
+#define GHCB_MSR_CPUID_VALUE_MASK 0xffffffff
+#define GHCB_MSR_CPUID_REG_POS 30
+#define GHCB_MSR_CPUID_REG_MASK 0x3
+#define GHCB_CPUID_REQ_EAX 0
+#define GHCB_CPUID_REQ_EBX 1
+#define GHCB_CPUID_REQ_ECX 2
+#define GHCB_CPUID_REQ_EDX 3
+#define GHCB_CPUID_REQ(fn, reg) \
+ (GHCB_MSR_CPUID_REQ | \
+ (((unsigned long)reg & GHCB_MSR_CPUID_REG_MASK) << GHCB_MSR_CPUID_REG_POS) | \
+ (((unsigned long)fn) << GHCB_MSR_CPUID_FUNC_POS))
+
+#define GHCB_MSR_TERM_REQ 0x100
+#define GHCB_MSR_TERM_REASON_SET_POS 12
+#define GHCB_MSR_TERM_REASON_SET_MASK 0xf
+#define GHCB_MSR_TERM_REASON_POS 16
+#define GHCB_MSR_TERM_REASON_MASK 0xff
+#define GHCB_SEV_TERM_REASON(reason_set, reason_val) \
+ (((((u64)reason_set) & GHCB_MSR_TERM_REASON_SET_MASK) << GHCB_MSR_TERM_REASON_SET_POS) | \
+ ((((u64)reason_val) & GHCB_MSR_TERM_REASON_MASK) << GHCB_MSR_TERM_REASON_POS))
+
+#define GHCB_SEV_ES_REASON_GENERAL_REQUEST 0
+#define GHCB_SEV_ES_REASON_PROTOCOL_UNSUPPORTED 1
+
+#define GHCB_RESP_CODE(v) ((v) & GHCB_MSR_INFO_MASK)
+
+#endif
diff --git a/arch/x86/include/asm/sev.h b/arch/x86/include/asm/sev.h
index cf1d957..fa5cd05 100644
--- a/arch/x86/include/asm/sev.h
+++ b/arch/x86/include/asm/sev.h
@@ -10,34 +10,12 @@

#include <linux/types.h>
#include <asm/insn.h>
+#include <asm/sev-common.h>

-#define GHCB_SEV_INFO 0x001UL
-#define GHCB_SEV_INFO_REQ 0x002UL
-#define GHCB_INFO(v) ((v) & 0xfffUL)
-#define GHCB_PROTO_MAX(v) (((v) >> 48) & 0xffffUL)
-#define GHCB_PROTO_MIN(v) (((v) >> 32) & 0xffffUL)
-#define GHCB_PROTO_OUR 0x0001UL
-#define GHCB_SEV_CPUID_REQ 0x004UL
-#define GHCB_CPUID_REQ_EAX 0
-#define GHCB_CPUID_REQ_EBX 1
-#define GHCB_CPUID_REQ_ECX 2
-#define GHCB_CPUID_REQ_EDX 3
-#define GHCB_CPUID_REQ(fn, reg) (GHCB_SEV_CPUID_REQ | \
- (((unsigned long)reg & 3) << 30) | \
- (((unsigned long)fn) << 32))
+#define GHCB_PROTO_OUR 0x0001UL
+#define GHCB_PROTOCOL_MAX 1ULL
+#define GHCB_DEFAULT_USAGE 0ULL

-#define GHCB_PROTOCOL_MAX 0x0001UL
-#define GHCB_DEFAULT_USAGE 0x0000UL
-
-#define GHCB_SEV_CPUID_RESP 0x005UL
-#define GHCB_SEV_TERMINATE 0x100UL
-#define GHCB_SEV_TERMINATE_REASON(reason_set, reason_val) \
- (((((u64)reason_set) & 0x7) << 12) | \
- ((((u64)reason_val) & 0xff) << 16))
-#define GHCB_SEV_ES_REASON_GENERAL_REQUEST 0
-#define GHCB_SEV_ES_REASON_PROTOCOL_UNSUPPORTED 1
-
-#define GHCB_SEV_GHCB_RESP_CODE(v) ((v) & 0xfff)
#define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); }

enum es_result {
diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index 0aa9f13..6ec8b3b 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c
@@ -26,13 +26,13 @@ static bool __init sev_es_check_cpu_features(void)

static void __noreturn sev_es_terminate(unsigned int reason)
{
- u64 val = GHCB_SEV_TERMINATE;
+ u64 val = GHCB_MSR_TERM_REQ;

/*
* Tell the hypervisor what went wrong - only reason-set 0 is
* currently supported.
*/
- val |= GHCB_SEV_TERMINATE_REASON(0, reason);
+ val |= GHCB_SEV_TERM_REASON(0, reason);

/* Request Guest Termination from Hypvervisor */
sev_es_wr_ghcb_msr(val);
@@ -47,15 +47,15 @@ static bool sev_es_negotiate_protocol(void)
u64 val;

/* Do the GHCB protocol version negotiation */
- sev_es_wr_ghcb_msr(GHCB_SEV_INFO_REQ);
+ sev_es_wr_ghcb_msr(GHCB_MSR_SEV_INFO_REQ);
VMGEXIT();
val = sev_es_rd_ghcb_msr();

- if (GHCB_INFO(val) != GHCB_SEV_INFO)
+ if (GHCB_MSR_INFO(val) != GHCB_MSR_SEV_INFO_RESP)
return false;

- if (GHCB_PROTO_MAX(val) < GHCB_PROTO_OUR ||
- GHCB_PROTO_MIN(val) > GHCB_PROTO_OUR)
+ if (GHCB_MSR_PROTO_MAX(val) < GHCB_PROTO_OUR ||
+ GHCB_MSR_PROTO_MIN(val) > GHCB_PROTO_OUR)
return false;

return true;
@@ -153,28 +153,28 @@ void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code)
sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EAX));
VMGEXIT();
val = sev_es_rd_ghcb_msr();
- if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP)
+ if (GHCB_RESP_CODE(val) != GHCB_MSR_CPUID_RESP)
goto fail;
regs->ax = val >> 32;

sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EBX));
VMGEXIT();
val = sev_es_rd_ghcb_msr();
- if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP)
+ if (GHCB_RESP_CODE(val) != GHCB_MSR_CPUID_RESP)
goto fail;
regs->bx = val >> 32;

sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_ECX));
VMGEXIT();
val = sev_es_rd_ghcb_msr();
- if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP)
+ if (GHCB_RESP_CODE(val) != GHCB_MSR_CPUID_RESP)
goto fail;
regs->cx = val >> 32;

sev_es_wr_ghcb_msr(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EDX));
VMGEXIT();
val = sev_es_rd_ghcb_msr();
- if (GHCB_SEV_GHCB_RESP_CODE(val) != GHCB_SEV_CPUID_RESP)
+ if (GHCB_RESP_CODE(val) != GHCB_MSR_CPUID_RESP)
goto fail;
regs->dx = val >> 32;

diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
index 84b3133..42f8a7b 100644
--- a/arch/x86/kvm/svm/svm.h
+++ b/arch/x86/kvm/svm/svm.h
@@ -20,6 +20,7 @@
#include <linux/bits.h>

#include <asm/svm.h>
+#include <asm/sev-common.h>

#define __sme_page_pa(x) __sme_set(page_to_pfn(x) << PAGE_SHIFT)

@@ -525,40 +526,9 @@ void svm_vcpu_unblocking(struct kvm_vcpu *vcpu);

/* sev.c */

-#define GHCB_VERSION_MAX 1ULL
-#define GHCB_VERSION_MIN 1ULL
-
-#define GHCB_MSR_INFO_POS 0
-#define GHCB_MSR_INFO_MASK (BIT_ULL(12) - 1)
-
-#define GHCB_MSR_SEV_INFO_RESP 0x001
-#define GHCB_MSR_SEV_INFO_REQ 0x002
-#define GHCB_MSR_VER_MAX_POS 48
-#define GHCB_MSR_VER_MAX_MASK 0xffff
-#define GHCB_MSR_VER_MIN_POS 32
-#define GHCB_MSR_VER_MIN_MASK 0xffff
-#define GHCB_MSR_CBIT_POS 24
-#define GHCB_MSR_CBIT_MASK 0xff
-#define GHCB_MSR_SEV_INFO(_max, _min, _cbit) \
- ((((_max) & GHCB_MSR_VER_MAX_MASK) << GHCB_MSR_VER_MAX_POS) | \
- (((_min) & GHCB_MSR_VER_MIN_MASK) << GHCB_MSR_VER_MIN_POS) | \
- (((_cbit) & GHCB_MSR_CBIT_MASK) << GHCB_MSR_CBIT_POS) | \
- GHCB_MSR_SEV_INFO_RESP)
-
-#define GHCB_MSR_CPUID_REQ 0x004
-#define GHCB_MSR_CPUID_RESP 0x005
-#define GHCB_MSR_CPUID_FUNC_POS 32
-#define GHCB_MSR_CPUID_FUNC_MASK 0xffffffff
-#define GHCB_MSR_CPUID_VALUE_POS 32
-#define GHCB_MSR_CPUID_VALUE_MASK 0xffffffff
-#define GHCB_MSR_CPUID_REG_POS 30
-#define GHCB_MSR_CPUID_REG_MASK 0x3
-
-#define GHCB_MSR_TERM_REQ 0x100
-#define GHCB_MSR_TERM_REASON_SET_POS 12
-#define GHCB_MSR_TERM_REASON_SET_MASK 0xf
-#define GHCB_MSR_TERM_REASON_POS 16
-#define GHCB_MSR_TERM_REASON_MASK 0xff
+#define GHCB_VERSION_MAX 1ULL
+#define GHCB_VERSION_MIN 1ULL
+

extern unsigned int max_sev_asid;