From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3FA08C433E5 for ; Mon, 24 Aug 2020 09:07:18 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1CFF82072D for ; Mon, 24 Aug 2020 09:07:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1CFF82072D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id C20A587C1C; Mon, 24 Aug 2020 09:07:17 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id R8U34ODblwwo; Mon, 24 Aug 2020 09:07:13 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id 5226787CE7; Mon, 24 Aug 2020 09:06:56 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 29CBBC0051; Mon, 24 Aug 2020 09:06:56 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id C032FC0051 for ; Mon, 24 Aug 2020 09:06:52 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id AD4D385F5C for ; Mon, 24 Aug 2020 09:06:52 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 5zQ64NHxoLIz for ; Mon, 24 Aug 2020 09:06:51 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by fraxinus.osuosl.org (Postfix) with ESMTPS id B258885F59 for ; Mon, 24 Aug 2020 09:06:51 +0000 (UTC) Received: from cap.home.8bytes.org (p4ff2bb8d.dip0.t-ipconnect.de [79.242.187.141]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 594D0168B; Mon, 24 Aug 2020 10:56:31 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Subject: [PATCH v6 74/76] x86/sev-es: Handle NMI State Date: Mon, 24 Aug 2020 10:55:09 +0200 Message-Id: <20200824085511.7553-75-joro@8bytes.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200824085511.7553-1-joro@8bytes.org> References: <20200824085511.7553-1-joro@8bytes.org> MIME-Version: 1.0 Cc: Juergen Gross , Tom Lendacky , Joerg Roedel , Mike Stunes , Kees Cook , kvm@vger.kernel.org, Peter Zijlstra , Cfir Cohen , Joerg Roedel , Dave Hansen , linux-kernel@vger.kernel.org, Sean Christopherson , virtualization@lists.linux-foundation.org, Martin Radev , Masami Hiramatsu , Andy Lutomirski , hpa@zytor.com, Erdem Aktas , David Rientjes , Dan Williams , Jiri Slaby X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" From: Joerg Roedel When running under SEV-ES the kernel has to tell the hypervisor when to open the NMI window again after an NMI was injected. This is done with an NMI-complete message to the hypervisor. Add code to the kernels NMI handler to send this message right at the beginning of do_nmi(). This always allows nesting NMIs. Signed-off-by: Joerg Roedel Link: https://lore.kernel.org/r/20200724160336.5435-74-joro@8bytes.org --- arch/x86/include/asm/sev-es.h | 7 +++++++ arch/x86/include/uapi/asm/svm.h | 1 + arch/x86/kernel/nmi.c | 6 ++++++ arch/x86/kernel/sev-es.c | 18 ++++++++++++++++++ 4 files changed, 32 insertions(+) diff --git a/arch/x86/include/asm/sev-es.h b/arch/x86/include/asm/sev-es.h index 6ca38dc378e0..21fdee11ac83 100644 --- a/arch/x86/include/asm/sev-es.h +++ b/arch/x86/include/asm/sev-es.h @@ -95,10 +95,17 @@ static __always_inline void sev_es_ist_exit(void) __sev_es_ist_exit(); } extern int sev_es_setup_ap_jump_table(struct real_mode_header *rmh); +extern void __sev_es_nmi_complete(void); +static __always_inline void sev_es_nmi_complete(void) +{ + if (static_branch_unlikely(&sev_es_enable_key)) + __sev_es_nmi_complete(); +} #else static inline void sev_es_ist_enter(struct pt_regs *regs) { } static inline void sev_es_ist_exit(void) { } static inline int sev_es_setup_ap_jump_table(struct real_mode_header *rmh) { return 0; } +static inline void sev_es_nmi_complete(void) { } #endif #endif diff --git a/arch/x86/include/uapi/asm/svm.h b/arch/x86/include/uapi/asm/svm.h index 20a05839dd9a..0f837339db66 100644 --- a/arch/x86/include/uapi/asm/svm.h +++ b/arch/x86/include/uapi/asm/svm.h @@ -84,6 +84,7 @@ /* SEV-ES software-defined VMGEXIT events */ #define SVM_VMGEXIT_MMIO_READ 0x80000001 #define SVM_VMGEXIT_MMIO_WRITE 0x80000002 +#define SVM_VMGEXIT_NMI_COMPLETE 0x80000003 #define SVM_VMGEXIT_AP_HLT_LOOP 0x80000004 #define SVM_VMGEXIT_AP_JUMP_TABLE 0x80000005 #define SVM_VMGEXIT_SET_AP_JUMP_TABLE 0 diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c index 951f098a4bf5..16ce58c7ed0f 100644 --- a/arch/x86/kernel/nmi.c +++ b/arch/x86/kernel/nmi.c @@ -478,6 +478,12 @@ DEFINE_IDTENTRY_RAW(exc_nmi) { bool irq_state; + /* + * Re-enable NMIs right here when running as an SEV-ES guest. This might + * cause nested NMIs, but those can be handled safely. + */ + sev_es_nmi_complete(); + if (IS_ENABLED(CONFIG_SMP) && arch_cpu_is_offline(smp_processor_id())) return; diff --git a/arch/x86/kernel/sev-es.c b/arch/x86/kernel/sev-es.c index 597ebb73411f..7202d2f5deb8 100644 --- a/arch/x86/kernel/sev-es.c +++ b/arch/x86/kernel/sev-es.c @@ -414,6 +414,24 @@ static bool vc_slow_virt_to_phys(struct ghcb *ghcb, struct es_em_ctxt *ctxt, /* Include code shared with pre-decompression boot stage */ #include "sev-es-shared.c" +void __sev_es_nmi_complete(void) +{ + struct ghcb_state state; + struct ghcb *ghcb; + + ghcb = sev_es_get_ghcb(&state); + + vc_ghcb_invalidate(ghcb); + ghcb_set_sw_exit_code(ghcb, SVM_VMGEXIT_NMI_COMPLETE); + ghcb_set_sw_exit_info_1(ghcb, 0); + ghcb_set_sw_exit_info_2(ghcb, 0); + + sev_es_wr_ghcb_msr(__pa(ghcb)); + VMGEXIT(); + + sev_es_put_ghcb(&state); +} + static u64 sev_es_get_jump_table_addr(void) { struct ghcb_state state; -- 2.28.0 _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization