[PATCH] x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

[PATCH] x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

[Peter Gonda]

Replace the hlt loop in handle_vc_boot_ghcb() with an
sev_es_terminate(). The hlt gives the system no indication the guest is
unhappy. The termination request will signal there was an error during
VC handling during boot.


Cc: Borislav Petkov <bp@alien8.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Peter Gonda <pgonda@google.com>
---
 arch/x86/kernel/sev.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index e6d316a01fdd..ae87fbf27724 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -1425,6 +1425,5 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs)
 fail:
 	show_regs(regs);
 
-	while (true)
-		halt();
+	sev_es_terminate(GHCB_SEV_ES_GEN_REQ);
 }
-- 
2.35.1.894.gb6a874cedc-goog

Re: [PATCH] x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

[Joerg Roedel]

On Thu, Mar 17, 2022 at 02:19:13PM -0700, Peter Gonda wrote:
> Replace the hlt loop in handle_vc_boot_ghcb() with an
> sev_es_terminate(). The hlt gives the system no indication the guest is
> unhappy. The termination request will signal there was an error during
> VC handling during boot.
> 
> 
> Cc: Borislav Petkov <bp@alien8.de>
> Cc: Tom Lendacky <thomas.lendacky@amd.com>
> Cc: Brijesh Singh <brijesh.singh@amd.com>
> Cc: Joerg Roedel <jroedel@suse.de>
> Cc: x86@kernel.org
> Cc: kvm@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Signed-off-by: Peter Gonda <pgonda@google.com>
> ---
>  arch/x86/kernel/sev.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
> index e6d316a01fdd..ae87fbf27724 100644
> --- a/arch/x86/kernel/sev.c
> +++ b/arch/x86/kernel/sev.c
> @@ -1425,6 +1425,5 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs)
>  fail:
>  	show_regs(regs);
>  
> -	while (true)
> -		halt();
> +	sev_es_terminate(GHCB_SEV_ES_GEN_REQ);

Reviewed-by: Joerg Roedel <jroedel@suse.de>

[tip: x86/sev] x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

[tip-bot2 for Peter Gonda]

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

Commit-ID:     453e580abcdb53f688d5711c68bec96bea35430d
Gitweb:        https://git.kernel.org/tip/453e580abcdb53f688d5711c68bec96bea35430d
Author:        Peter Gonda <pgonda@google.com>
AuthorDate:    Thu, 17 Mar 2022 14:19:13 -07:00
Committer:     Borislav Petkov <bp@suse.de>
CommitterDate: Tue, 05 Apr 2022 19:33:55 +02:00

x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

Replace the halt loop in handle_vc_boot_ghcb() with an
sev_es_terminate(). The HLT gives the system no indication the guest is
unhappy. The termination request will signal there was an error during
VC handling during boot.

Signed-off-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20220317211913.1397427-1-pgonda@google.com
---
 arch/x86/kernel/sev.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index e6d316a..ae87fbf 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -1425,6 +1425,5 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs)
 fail:
 	show_regs(regs);
 
-	while (true)
-		halt();
+	sev_es_terminate(GHCB_SEV_ES_GEN_REQ);
 }

[tip: x86/sev] x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

[tip-bot2 for Peter Gonda]

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

Commit-ID:     e720ea52e85c9d00cf8c5769795d0a3e585524f6
Gitweb:        https://git.kernel.org/tip/e720ea52e85c9d00cf8c5769795d0a3e585524f6
Author:        Peter Gonda <pgonda@google.com>
AuthorDate:    Thu, 17 Mar 2022 14:19:13 -07:00
Committer:     Borislav Petkov <bp@suse.de>
CommitterDate: Fri, 08 Apr 2022 10:57:35 +02:00

x86/sev-es: Replace open-coded hlt-loop with sev_es_terminate()

Replace the halt loop in handle_vc_boot_ghcb() with an
sev_es_terminate(). The HLT gives the system no indication the guest is
unhappy. The termination request will signal there was an error during
VC handling during boot.

  [ bp: Update it to pass the reason set too. ]

Signed-off-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20220317211913.1397427-1-pgonda@google.com
---
 arch/x86/kernel/sev.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kernel/sev.c b/arch/x86/kernel/sev.c
index ace43e1..f01f455 100644
--- a/arch/x86/kernel/sev.c
+++ b/arch/x86/kernel/sev.c
@@ -1982,8 +1982,7 @@ bool __init handle_vc_boot_ghcb(struct pt_regs *regs)
 fail:
 	show_regs(regs);
 
-	while (true)
-		halt();
+	sev_es_terminate(SEV_TERM_SET_GEN, GHCB_SEV_ES_GEN_REQ);
 }
 
 /*