[PATCH 60/70] x86/sev-es: Handle #DB Events
From: Joerg Roedel <joro@8bytes.org>
Date: 2020-03-19 09:16:09
Also in:
kvm, lkml
Subsystem:
the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: Joerg Roedel <redacted> 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 <redacted> --- 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 f22b361f6b60..bc553aae31d2 100644
--- a/arch/x86/kernel/sev-es.c
+++ b/arch/x86/kernel/sev-es.c@@ -752,6 +752,15 @@ static enum es_result vc_handle_vmmcall(struct ghcb *ghcb, return ES_OK; } +static enum es_result vc_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 vc_handle_exitcode(struct es_em_ctxt *ctxt, struct ghcb *ghcb, unsigned long exit_code,
@@ -766,6 +775,9 @@ static enum es_result vc_handle_exitcode(struct es_em_ctxt *ctxt, case SVM_EXIT_WRITE_DR7: result = vc_handle_dr7_write(ghcb, ctxt, early); break; + case SVM_EXIT_EXCP_BASE + X86_TRAP_DB: + result = vc_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