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

From: tip-bot2 for Joerg Roedel
Date: Thu Mar 18 2021 - 18:10:55 EST


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

Commit-ID: f15a0a732aefb46f999c2a8aa8f9f16e71cec5b2
Gitweb: https://git.kernel.org/tip/f15a0a732aefb46f999c2a8aa8f9f16e71cec5b2
Author: Joerg Roedel <jroedel@xxxxxxx>
AuthorDate: Fri, 12 Mar 2021 13:38:24 +01:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Thu, 18 Mar 2021 23:04:12 +01:00

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

There are a few places left in the SEV-ES C code where hlt loops and/or
terminate requests are implemented. Replace them all with calls to
sev_es_terminate().

Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lkml.kernel.org/r/20210312123824.306-9-joro@xxxxxxxxxx
---
arch/x86/boot/compressed/sev-es.c | 12 +++---------
arch/x86/kernel/sev-es-shared.c | 10 +++-------
2 files changed, 6 insertions(+), 16 deletions(-)

diff --git a/arch/x86/boot/compressed/sev-es.c b/arch/x86/boot/compressed/sev-es.c
index 27826c2..d904bd5 100644
--- a/arch/x86/boot/compressed/sev-es.c
+++ b/arch/x86/boot/compressed/sev-es.c
@@ -200,14 +200,8 @@ void do_boot_stage2_vc(struct pt_regs *regs, unsigned long exit_code)
}

finish:
- if (result == ES_OK) {
+ if (result == ES_OK)
vc_finish_insn(&ctxt);
- } else if (result != ES_RETRY) {
- /*
- * For now, just halt the machine. That makes debugging easier,
- * later we just call sev_es_terminate() here.
- */
- while (true)
- asm volatile("hlt\n");
- }
+ else if (result != ES_RETRY)
+ sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
}
diff --git a/arch/x86/kernel/sev-es-shared.c b/arch/x86/kernel/sev-es-shared.c
index 387b716..0aa9f13 100644
--- a/arch/x86/kernel/sev-es-shared.c
+++ b/arch/x86/kernel/sev-es-shared.c
@@ -24,7 +24,7 @@ static bool __init sev_es_check_cpu_features(void)
return true;
}

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

@@ -206,12 +206,8 @@ void __init do_vc_no_ghcb(struct pt_regs *regs, unsigned long exit_code)
return;

fail:
- sev_es_wr_ghcb_msr(GHCB_SEV_TERMINATE);
- VMGEXIT();
-
- /* Shouldn't get here - if we do halt the machine */
- while (true)
- asm volatile("hlt\n");
+ /* Terminate the guest */
+ sev_es_terminate(GHCB_SEV_ES_REASON_GENERAL_REQUEST);
}

static enum es_result vc_insn_string_read(struct es_em_ctxt *ctxt,