[PATCH Part1 RFC v2 07/20] x86/sev: Define error codes for reason set 1.
From: Brijesh Singh
Date: Fri Apr 30 2021 - 08:17:30 EST
GHCB specification defines the reason code for reason set 0. The reason
codes defined in the set 0 do not cover all possible causes for a guest
to request termination.
The reason set 1 to 255 is reserved for the vendor-specific codes.
Use the reason set 1 for the Linux guest. Define an error codes for
reason set 1.
While at it, change the sev_es_terminate() to accept the reason set
parameter.
Signed-off-by: Brijesh Singh <brijesh.singh@xxxxxxx>
---
arch/x86/boot/compressed/sev.c | 6 +++---
arch/x86/include/asm/sev-common.h | 5 +++++
arch/x86/kernel/sev-shared.c | 6 +++---
arch/x86/kernel/sev.c | 4 ++--
4 files changed, 13 insertions(+), 8 deletions(-)
diff --git a/arch/x86/boot/compressed/sev.c b/arch/x86/boot/compressed/sev.c
index 670e998fe930..6d9055427f37 100644
--- a/arch/x86/boot/compressed/sev.c
+++ b/arch/x86/boot/compressed/sev.c
@@ -122,7 +122,7 @@ static enum es_result vc_read_mem(struct es_em_ctxt *ctxt,
static bool early_setup_sev_es(void)
{
if (!sev_es_negotiate_protocol())
- sev_es_terminate(GHCB_SEV_ES_REASON_PROTOCOL_UNSUPPORTED);
+ sev_es_terminate(0, GHCB_SEV_ES_REASON_PROTOCOL_UNSUPPORTED);
if (set_page_decrypted((unsigned long)&boot_ghcb_page))
return false;
@@ -175,7 +175,7 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code)
enum es_result result;
if (!boot_ghcb && !early_setup_sev_es())
- sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
+ sev_es_terminate(0, GHCB_SEV_ES_REASON_GENERAL_REQUEST);
vc_ghcb_invalidate(boot_ghcb);
result = vc_init_em_ctxt(&ctxt, regs, exit_code);
@@ -202,5 +202,5 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code)
if (result == ES_OK)
vc_finish_insn(&ctxt);
else if (result != ES_RETRY)
- sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
+ sev_es_terminate(0, GHCB_SEV_ES_REASON_GENERAL_REQUEST);
}
diff --git a/arch/x86/include/asm/sev-common.h b/arch/x86/include/asm/sev-common.h
index 07b8612bf182..733fca403ae5 100644
--- a/arch/x86/include/asm/sev-common.h
+++ b/arch/x86/include/asm/sev-common.h
@@ -128,4 +128,9 @@ struct __packed snp_page_state_change {
#define GHCB_RESP_CODE(v) ((v) & GHCB_MSR_INFO_MASK)
+/* Linux specific reason codes (used with reason set 1) */
+#define GHCB_TERM_REGISTER 0 /* GHCB GPA registration failure */
+#define GHCB_TERM_PSC 1 /* Page State Change faiilure */
+#define GHCB_TERM_PVALIDATE 2 /* Pvalidate failure */
+
#endif
diff --git a/arch/x86/kernel/sev-shared.c b/arch/x86/kernel/sev-shared.c
index 874f911837db..3f9b06a04395 100644
--- a/arch/x86/kernel/sev-shared.c
+++ b/arch/x86/kernel/sev-shared.c
@@ -32,7 +32,7 @@ static bool __init sev_es_check_cpu_features(void)
return true;
}
-static void __noreturn sev_es_terminate(unsigned int reason)
++static void __noreturn sev_es_terminate(unsigned int set, unsigned int reason)
{
u64 val = GHCB_MSR_TERM_REQ;
@@ -40,7 +40,7 @@ static void __noreturn sev_es_terminate(unsigned int reason)
* Tell the hypervisor what went wrong - only reason-set 0 is
* currently supported.
*/
- val |= GHCB_SEV_TERM_REASON(0, reason);
+ val |= GHCB_SEV_TERM_REASON(set, reason);
/* Request Guest Termination from Hypvervisor */
sev_es_wr_ghcb_msr(val);
@@ -240,7 +240,7 @@ void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code)
fail:
/* Terminate the guest */
- sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
+ sev_es_terminate(0, GHCB_SEV_ES_REASON_GENERAL_REQUEST);
}
static enum es_result vc_insn_string_read(struct es_em_ctxt *ctxt,
diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index 9578c82832aa..97be0fe666ab 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -1383,7 +1383,7 @@ DEFINE_IDTENTRY_VC_SAFE_STACK(exc_vmm_communication)
show_regs(regs);
/* Ask hypervisor to sev_es_terminate */
- sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
+ sev_es_terminate(0, GHCB_SEV_ES_REASON_GENERAL_REQUEST);
/* If that fails and we get here - just panic */
panic("Returned from Terminate-Request to Hypervisor\n");
@@ -1416,7 +1416,7 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs)
/* Do initial setup or terminate the guest */
if (unlikely(boot_ghcb == NULL && !sev_es_setup_ghcb()))
- sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
+ sev_es_terminate(0, GHCB_SEV_ES_REASON_GENERAL_REQUEST);
vc_ghcb_invalidate(boot_ghcb);
--
2.17.1