From: Joerg Roedel <jroedel@xxxxxxx>
Handle #VC exceptions caused by #DB exceptions in the guest. Do not
forward them to the hypervisor and handle them with do_debug() instead.
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
arch/x86/kernel/sev-es.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c
index 1b873d00e38f..700f75fc13e7 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c
@@ -361,6 +361,15 @@ static enum es_result handle_vmmcall(struct ghcb *ghcb,
return ES_OK;
}
+static enum es_result handle_db_exception(struct ghcb *ghcb,
+ struct es_em_ctxt *ctxt)
+{
+ do_debug(ctxt->regs, 0);
+
+ /* Exception event, do not advance RIP */
+ return ES_RETRY;
+}
+
static enum es_result handle_vc_exception(struct es_em_ctxt *ctxt,
struct ghcb *ghcb,
unsigned long exit_code,
@@ -375,6 +384,9 @@ static enum es_result handle_vc_exception(struct es_em_ctxt *ctxt,
case SVM_EXIT_WRITE_DR7:
result = handle_dr7_write(ghcb, ctxt, early);
break;
+ case SVM_EXIT_EXCP_BASE + X86_TRAP_DB:
+ result = handle_db_exception(ghcb, ctxt);
+ break;
case SVM_EXIT_EXCP_BASE + X86_TRAP_AC:
do_alignment_check(ctxt->regs, 0);
result = ES_RETRY;
--
2.17.1
