From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roedel Subject: [PATCH 60/70] x86/sev-es: Handle #DB Events Date: Thu, 19 Mar 2020 10:13:57 +0100 Message-ID: <20200319091407.1481-61-joro@8bytes.org> References: <20200319091407.1481-1-joro@8bytes.org> Return-path: In-Reply-To: <20200319091407.1481-1-joro@8bytes.org> Sender: kvm-owner@vger.kernel.org To: x86@kernel.org Cc: hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Hellstrom , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , Kees Cook , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, Joerg Roedel , Joerg Roedel List-Id: virtualization@lists.linuxfoundation.org From: Joerg Roedel 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 --- 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