From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH v3 53/75] x86/sev-es: Handle MSR events Date: Mon, 25 May 2020 11:53:46 +0200 Message-ID: <20200525095346.GF25636@zn.tnic> References: <20200428151725.31091-1-joro@8bytes.org> <20200428151725.31091-54-joro@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20200428151725.31091-54-joro@8bytes.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" To: Joerg Roedel Cc: Juergen Gross , Tom Lendacky , Thomas Hellstrom , Dave Hansen , Mike Stunes , Kees Cook , kvm@vger.kernel.org, Peter Zijlstra , Cfir Cohen , x86@kernel.org, linux-kernel@vger.kernel.org, virtualization@lists.linux-foundation.org, Joerg Roedel , Masami Hiramatsu , Andy Lutomirski , hpa@zytor.com, Erdem Aktas , David Rientjes , Dan Williams , Jiri Slaby List-Id: virtualization@lists.linuxfoundation.org On Tue, Apr 28, 2020 at 05:17:03PM +0200, Joerg Roedel wrote: > From: Tom Lendacky > > Implement a handler for #VC exceptions caused by RDMSR/WRMSR > instructions. > > Signed-off-by: Tom Lendacky > [ jroedel@suse.de: Adapt to #VC handling infrastructure ] > Co-developed-by: Joerg Roedel > Signed-off-by: Joerg Roedel > --- > arch/x86/kernel/sev-es.c | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c > index 84958a82f8e0..e43bba4c7d79 100644 > --- a/arch/x86/kernel/sev-es.c > +++ b/arch/x86/kernel/sev-es.c > @@ -316,6 +316,31 @@ static phys_addr_t vc_slow_virt_to_phys(struct ghcb *ghcb, unsigned long vaddr) > /* Include code shared with pre-decompression boot stage */ > #include "sev-es-shared.c" > > +static enum es_result vc_handle_msr(struct ghcb *ghcb, struct es_em_ctxt *ctxt) > +{ > + struct pt_regs *regs = ctxt->regs; > + enum es_result ret; > + u64 exit_info_1; > + A comment pls: /* Is it a WRMSR? */ > + exit_info_1 = (ctxt->insn.opcode.bytes[1] == 0x30) ? 1 : 0; > + > + ghcb_set_rcx(ghcb, regs->cx); > + if (exit_info_1) { > + ghcb_set_rax(ghcb, regs->ax); > + ghcb_set_rdx(ghcb, regs->dx); > + exit_info_1 = 1; No need to set it again - you just did above. :) -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette