From patchwork Tue Jun 1 07:16:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 451913 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 5CE30C4708F for ; Tue, 1 Jun 2021 07:17:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3639B610A8 for ; Tue, 1 Jun 2021 07:17:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231139AbhFAHSm (ORCPT ); Tue, 1 Jun 2021 03:18:42 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:60753 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230326AbhFAHSl (ORCPT ); Tue, 1 Jun 2021 03:18:41 -0400 Received: from mail-wm1-f69.google.com ([209.85.128.69]) by youngberry.canonical.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1lnye4-0002km-8Z for stable@vger.kernel.org; Tue, 01 Jun 2021 07:17:00 +0000 Received: by mail-wm1-f69.google.com with SMTP id l185-20020a1c25c20000b029014b0624775eso760569wml.6 for ; Tue, 01 Jun 2021 00:17:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=emyUtAWEgDmFnmhXG3HYQB6UCm32cWFuLm9kPRBLFac=; b=D2+hl9C1VxCzI1yUzoG3XCT0lnVPLFRlOo3vswYATFZd3mFilqZ1SCxhyV5yuIFGEg Vtq5plrburcywxYURZ/6Kd/iEt9xbE7wY1eipufvVujcd4gx4hWvX4bgm4k3oBT3iyWb RI5ymQE2VRliyKRi7Q4ErlFmaJrP0ja+APbVdqvLe3h+yjE00IwHTfRspqyW5luq8zor ADuWRb+F7UHsZADiXWS33/J9Ac4i9AuJe+55Y6YQX6Ip2UZl6MKIRcqpF+exJm944Ph5 COF6NX8wohsDLHOmRZOlRjh5OtHhB5WRqR0Ud/IYV/adpkXjkHJRm6TXc37Q9MWrnLE/ +yyw== X-Gm-Message-State: AOAM533TweAZDO1tWbDrzdzaokBubLRozNA3FXvECYijCqgsdxq6mcmM 8bpFsBNq0K9oxdrGY9nwURYheCQDT5Whag1Vgnj2QGuFuGxn3ubq/n6ksQhfPX+BizxMmPqU4LU A8hk4i8TPi69ORSGcrKIwqtw9gkCoEkxaDQ== X-Received: by 2002:a05:6000:18a4:: with SMTP id b4mr24772772wri.24.1622531819761; Tue, 01 Jun 2021 00:16:59 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwV6REufv9sxaOSiw58y5Vatl+jTKAcRUTHaP2brj73CCq0LAEG/KOOw1ZnU+ZvqyOQjub/2A== X-Received: by 2002:a05:6000:18a4:: with SMTP id b4mr24772761wri.24.1622531819612; Tue, 01 Jun 2021 00:16:59 -0700 (PDT) Received: from localhost.localdomain (xdsl-188-155-185-9.adslplus.ch. [188.155.185.9]) by smtp.gmail.com with ESMTPSA id b188sm2083869wmh.18.2021.06.01.00.16.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Jun 2021 00:16:59 -0700 (PDT) From: Krzysztof Kozlowski To: stable@vger.kernel.org Cc: Andrea Righi , Paolo Bonzini , Vitaly Kuznetsov , Krzysztof Kozlowski Subject: [PATCH v3 | stable v5.12 1/3] x86/kvm: Teardown PV features on boot CPU as well Date: Tue, 1 Jun 2021 09:16:42 +0200 Message-Id: <20210601071644.6055-1-krzysztof.kozlowski@canonical.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vitaly Kuznetsov commit 8b79feffeca28c5459458fe78676b081e87c93a4 upstream. Various PV features (Async PF, PV EOI, steal time) work through memory shared with hypervisor and when we restore from hibernation we must properly teardown all these features to make sure hypervisor doesn't write to stale locations after we jump to the previously hibernated kernel (which can try to place anything there). For secondary CPUs the job is already done by kvm_cpu_down_prepare(), register syscore ops to do the same for boot CPU. Krzysztof: This fixes memory corruption visible after second resume from hibernation: BUG: Bad page state in process dbus-daemon pfn:18b01 page:ffffea000062c040 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 compound_mapcount: -30591 flags: 0xfffffc0078141(locked|error|workingset|writeback|head|mappedtodisk|reclaim) raw: 000fffffc0078141 dead0000000002d0 dead000000000100 0000000000000000 raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: PAGE_FLAGS_CHECK_AT_PREP flag set bad because of flags: 0x78141(locked|error|workingset|writeback|head|mappedtodisk|reclaim) Signed-off-by: Vitaly Kuznetsov Message-Id: <20210414123544.1060604-3-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini Signed-off-by: Andrea Righi [krzysztof: Extend the commit message, adjust for v5.10 context] Signed-off-by: Krzysztof Kozlowski Acked-by: Paolo Bonzini --- arch/x86/kernel/kvm.c | 57 +++++++++++++++++++++++++++++++------------ 1 file changed, 41 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 78bb0fae3982..5ae57be19187 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -460,6 +461,25 @@ static bool pv_tlb_flush_supported(void) static DEFINE_PER_CPU(cpumask_var_t, __pv_cpu_mask); +static void kvm_guest_cpu_offline(void) +{ + kvm_disable_steal_time(); + if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) + wrmsrl(MSR_KVM_PV_EOI_EN, 0); + kvm_pv_disable_apf(); + apf_task_wake_all(); +} + +static int kvm_cpu_online(unsigned int cpu) +{ + unsigned long flags; + + local_irq_save(flags); + kvm_guest_cpu_init(); + local_irq_restore(flags); + return 0; +} + #ifdef CONFIG_SMP static bool pv_ipi_supported(void) @@ -587,31 +607,34 @@ static void __init kvm_smp_prepare_boot_cpu(void) kvm_spinlock_init(); } -static void kvm_guest_cpu_offline(void) +static int kvm_cpu_down_prepare(unsigned int cpu) { - kvm_disable_steal_time(); - if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) - wrmsrl(MSR_KVM_PV_EOI_EN, 0); - kvm_pv_disable_apf(); - apf_task_wake_all(); -} + unsigned long flags; -static int kvm_cpu_online(unsigned int cpu) -{ - local_irq_disable(); - kvm_guest_cpu_init(); - local_irq_enable(); + local_irq_save(flags); + kvm_guest_cpu_offline(); + local_irq_restore(flags); return 0; } -static int kvm_cpu_down_prepare(unsigned int cpu) +#endif + +static int kvm_suspend(void) { - local_irq_disable(); kvm_guest_cpu_offline(); - local_irq_enable(); + return 0; } -#endif + +static void kvm_resume(void) +{ + kvm_cpu_online(raw_smp_processor_id()); +} + +static struct syscore_ops kvm_syscore_ops = { + .suspend = kvm_suspend, + .resume = kvm_resume, +}; static void kvm_flush_tlb_others(const struct cpumask *cpumask, const struct flush_tlb_info *info) @@ -681,6 +704,8 @@ static void __init kvm_guest_init(void) kvm_guest_cpu_init(); #endif + register_syscore_ops(&kvm_syscore_ops); + /* * Hard lockup detection is enabled by default. Disable it, as guests * can get false positives too easily, for example if the host is From patchwork Tue Jun 1 07:16:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 453209 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 9C850C47092 for ; Tue, 1 Jun 2021 07:17:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7AD816139A for ; Tue, 1 Jun 2021 07:17:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230326AbhFAHSn (ORCPT ); Tue, 1 Jun 2021 03:18:43 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:60759 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231140AbhFAHSm (ORCPT ); Tue, 1 Jun 2021 03:18:42 -0400 Received: from mail-wm1-f70.google.com ([209.85.128.70]) by youngberry.canonical.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1lnye5-0002lO-80 for stable@vger.kernel.org; Tue, 01 Jun 2021 07:17:01 +0000 Received: by mail-wm1-f70.google.com with SMTP id h18-20020a05600c3512b029018434eb1bd8so765987wmq.2 for ; Tue, 01 Jun 2021 00:17:01 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Q3ONUsJUAquB6CIMKNSbBcjFZ7oTwCcRvLqLR9mB/5U=; b=aaccIB7qQwd7XzjXxqpxzL+ygIG5forvv59ezR4cbH85e2Be/DkLllVZBLtpLLpo8s vRVQtKd8fxdqdia9OSrMox8/Pptt076QnMxeMR8gBaL+8F4dB35Pfkg65IQ6IrrL5qcH 32pi1I0aEFU3LogNjUzz4RTkQDwX8wFqQEbqzbKAOhrxn11gX7z9zO+ysTgvD28Usu9d AhBLV+eyxTtYDhFt1HuJ7h4DywnHbcHhz8ovh3ukoGtI2kl3K4+ix5iDXNAujVTnuAjb WOI9heNorKOULa/NJOTeJu2dbnDJ+fJO44oVu3srSmkm1Pfq9IzuyD0rz+yj8mmqAqbO PVCQ== X-Gm-Message-State: AOAM530judKQuA6A5KMfPC6K30SNEFviM4McE+v6x3CGku8AlZzKYI2I BmkrYgjRhJVkTn9EPvoIeuTCSGns7eErvXHJ8Nz4+4Isj7y58sZIZsh5gKydL3Mnve9nQU8g4I6 Ai/GRsKrXByr1fmWjBFVGRRYxbXy9hxHsfQ== X-Received: by 2002:a05:600c:3786:: with SMTP id o6mr6162401wmr.170.1622531820538; Tue, 01 Jun 2021 00:17:00 -0700 (PDT) X-Google-Smtp-Source: ABdhPJztb4xhX8L22FvmQkboW+Edf91JphzCzKMcqMjisVQqczE4SKPw0RMGKla/j7ayF/C9P6R6Pw== X-Received: by 2002:a05:600c:3786:: with SMTP id o6mr6162389wmr.170.1622531820422; Tue, 01 Jun 2021 00:17:00 -0700 (PDT) Received: from localhost.localdomain (xdsl-188-155-185-9.adslplus.ch. [188.155.185.9]) by smtp.gmail.com with ESMTPSA id b188sm2083869wmh.18.2021.06.01.00.16.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Jun 2021 00:16:59 -0700 (PDT) From: Krzysztof Kozlowski To: stable@vger.kernel.org Cc: Andrea Righi , Paolo Bonzini , Vitaly Kuznetsov , Krzysztof Kozlowski Subject: [PATCH v3 | stable v5.12 2/3] x86/kvm: Disable kvmclock on all CPUs on shutdown Date: Tue, 1 Jun 2021 09:16:43 +0200 Message-Id: <20210601071644.6055-2-krzysztof.kozlowski@canonical.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210601071644.6055-1-krzysztof.kozlowski@canonical.com> References: <20210601071644.6055-1-krzysztof.kozlowski@canonical.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vitaly Kuznetsov commit c02027b5742b5aa804ef08a4a9db433295533046 upstream. Currenly, we disable kvmclock from machine_shutdown() hook and this only happens for boot CPU. We need to disable it for all CPUs to guard against memory corruption e.g. on restore from hibernate. Note, writing '0' to kvmclock MSR doesn't clear memory location, it just prevents hypervisor from updating the location so for the short while after write and while CPU is still alive, the clock remains usable and correct so we don't need to switch to some other clocksource. Signed-off-by: Vitaly Kuznetsov Message-Id: <20210414123544.1060604-4-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini Signed-off-by: Andrea Righi Signed-off-by: Krzysztof Kozlowski --- arch/x86/include/asm/kvm_para.h | 4 ++-- arch/x86/kernel/kvm.c | 1 + arch/x86/kernel/kvmclock.c | 5 +---- 3 files changed, 4 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index 338119852512..9c56e0defd45 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -7,8 +7,6 @@ #include #include -extern void kvmclock_init(void); - #ifdef CONFIG_KVM_GUEST bool kvm_check_and_clear_guest_paused(void); #else @@ -86,6 +84,8 @@ static inline long kvm_hypercall4(unsigned int nr, unsigned long p1, } #ifdef CONFIG_KVM_GUEST +void kvmclock_init(void); +void kvmclock_disable(void); bool kvm_para_available(void); unsigned int kvm_arch_para_features(void); unsigned int kvm_arch_para_hints(void); diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 5ae57be19187..2ebb93c34bc5 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -468,6 +468,7 @@ static void kvm_guest_cpu_offline(void) wrmsrl(MSR_KVM_PV_EOI_EN, 0); kvm_pv_disable_apf(); apf_task_wake_all(); + kvmclock_disable(); } static int kvm_cpu_online(unsigned int cpu) diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index 1fc0962c89c0..cf869de98eec 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -220,11 +220,9 @@ static void kvm_crash_shutdown(struct pt_regs *regs) } #endif -static void kvm_shutdown(void) +void kvmclock_disable(void) { native_write_msr(msr_kvm_system_time, 0, 0); - kvm_disable_steal_time(); - native_machine_shutdown(); } static void __init kvmclock_init_mem(void) @@ -351,7 +349,6 @@ void __init kvmclock_init(void) #endif x86_platform.save_sched_clock_state = kvm_save_sched_clock_state; x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state; - machine_ops.shutdown = kvm_shutdown; #ifdef CONFIG_KEXEC_CORE machine_ops.crash_shutdown = kvm_crash_shutdown; #endif From patchwork Tue Jun 1 07:16:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 451912 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 B8428C4708F for ; Tue, 1 Jun 2021 07:17:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 95817610A8 for ; Tue, 1 Jun 2021 07:17:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231928AbhFAHSs (ORCPT ); Tue, 1 Jun 2021 03:18:48 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:60766 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231140AbhFAHSr (ORCPT ); Tue, 1 Jun 2021 03:18:47 -0400 Received: from mail-wm1-f70.google.com ([209.85.128.70]) by youngberry.canonical.com with esmtps (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.93) (envelope-from ) id 1lnye7-0002n6-2c for stable@vger.kernel.org; Tue, 01 Jun 2021 07:17:03 +0000 Received: by mail-wm1-f70.google.com with SMTP id 128-20020a1c04860000b0290196f3c0a927so763366wme.3 for ; Tue, 01 Jun 2021 00:17:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=he9Z7jKEL7xWBcQIT6GeTQdygtNqBsNfzV0spRxTzdQ=; b=iHN5h/1IBWeCGvG6YlDO2atgvUPauprVHR7toiPfbEWPCBvM5Yw/Jx0mByb/r97Yw8 fH1qDDY/JyNTdxzr7ZyzojMz63fX4OTWQ1s8BQaAXeZRB4NCdBZdrw8aW1jNJ4UPjwGc xCtSaX8ZZ/TEtV6wuZY5JXXYekFhRfDAi5nMUBJEwotc5d/WxJYU16xNCgwQ8eXnE8jy GgU99fKDLvzQhy6Ru1LF4MbkQoZXCcL8a8WCaiY5M5Hfp0f88K+5nTww+r+OBZWz5Zaj UvX3CEgWolDyjeT3bnd02frApb4zmmmfpANZUyThf440CGPhJPWUleCdKBPQl+nTH47m cf+Q== X-Gm-Message-State: AOAM531VJeFqExuTFvPn8E5ElI/ZxH4jUCAUgh6FARMOXLeKxnT1X2w+ pVHSRDUR16LXAKS2xfvTjYJzD1bXJDFepivSVIu6Hb9gNZ2UX3tPGdyn3ufrUk9J5sfLphQ0ZDv E3YpNnE6KDnwxHQt80Su7kcg+NuW1281sqA== X-Received: by 2002:a1c:ed0a:: with SMTP id l10mr24923185wmh.151.1622531821781; Tue, 01 Jun 2021 00:17:01 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwYWL9fpi3tw8PcECQrgIM4VsfSESA2dQim2qQfZMPbtDHFNYnY68Np2p9PSlsS5i02YjmkfQ== X-Received: by 2002:a1c:ed0a:: with SMTP id l10mr24923168wmh.151.1622531821652; Tue, 01 Jun 2021 00:17:01 -0700 (PDT) Received: from localhost.localdomain (xdsl-188-155-185-9.adslplus.ch. [188.155.185.9]) by smtp.gmail.com with ESMTPSA id b188sm2083869wmh.18.2021.06.01.00.17.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Jun 2021 00:17:00 -0700 (PDT) From: Krzysztof Kozlowski To: stable@vger.kernel.org Cc: Andrea Righi , Paolo Bonzini , Vitaly Kuznetsov , Krzysztof Kozlowski Subject: [PATCH v3 | stable v5.12 3/3] x86/kvm: Disable all PV features on crash Date: Tue, 1 Jun 2021 09:16:44 +0200 Message-Id: <20210601071644.6055-3-krzysztof.kozlowski@canonical.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20210601071644.6055-1-krzysztof.kozlowski@canonical.com> References: <20210601071644.6055-1-krzysztof.kozlowski@canonical.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Vitaly Kuznetsov commit 3d6b84132d2a57b5a74100f6923a8feb679ac2ce upstream. Crash shutdown handler only disables kvmclock and steal time, other PV features remain active so we risk corrupting memory or getting some side-effects in kdump kernel. Move crash handler to kvm.c and unify with CPU offline. Signed-off-by: Vitaly Kuznetsov Message-Id: <20210414123544.1060604-5-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini Signed-off-by: Krzysztof Kozlowski --- arch/x86/include/asm/kvm_para.h | 6 ----- arch/x86/kernel/kvm.c | 44 ++++++++++++++++++++++++--------- arch/x86/kernel/kvmclock.c | 21 ---------------- 3 files changed, 32 insertions(+), 39 deletions(-) diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index 9c56e0defd45..69299878b200 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -92,7 +92,6 @@ unsigned int kvm_arch_para_hints(void); void kvm_async_pf_task_wait_schedule(u32 token); void kvm_async_pf_task_wake(u32 token); u32 kvm_read_and_reset_apf_flags(void); -void kvm_disable_steal_time(void); bool __kvm_handle_async_pf(struct pt_regs *regs, u32 token); DECLARE_STATIC_KEY_FALSE(kvm_async_pf_enabled); @@ -137,11 +136,6 @@ static inline u32 kvm_read_and_reset_apf_flags(void) return 0; } -static inline void kvm_disable_steal_time(void) -{ - return; -} - static __always_inline bool kvm_handle_async_pf(struct pt_regs *regs, u32 token) { return false; diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 2ebb93c34bc5..919411a0117d 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -38,6 +38,7 @@ #include #include #include +#include #include DEFINE_STATIC_KEY_FALSE(kvm_async_pf_enabled); @@ -375,6 +376,14 @@ static void kvm_pv_disable_apf(void) pr_info("Unregister pv shared memory for cpu %d\n", smp_processor_id()); } +static void kvm_disable_steal_time(void) +{ + if (!has_steal_clock) + return; + + wrmsr(MSR_KVM_STEAL_TIME, 0, 0); +} + static void kvm_pv_guest_cpu_reboot(void *unused) { /* @@ -417,14 +426,6 @@ static u64 kvm_steal_clock(int cpu) return steal; } -void kvm_disable_steal_time(void) -{ - if (!has_steal_clock) - return; - - wrmsr(MSR_KVM_STEAL_TIME, 0, 0); -} - static inline void __set_percpu_decrypted(void *ptr, unsigned long size) { early_set_memory_decrypted((unsigned long) ptr, size); @@ -461,13 +462,14 @@ static bool pv_tlb_flush_supported(void) static DEFINE_PER_CPU(cpumask_var_t, __pv_cpu_mask); -static void kvm_guest_cpu_offline(void) +static void kvm_guest_cpu_offline(bool shutdown) { kvm_disable_steal_time(); if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) wrmsrl(MSR_KVM_PV_EOI_EN, 0); kvm_pv_disable_apf(); - apf_task_wake_all(); + if (!shutdown) + apf_task_wake_all(); kvmclock_disable(); } @@ -613,7 +615,7 @@ static int kvm_cpu_down_prepare(unsigned int cpu) unsigned long flags; local_irq_save(flags); - kvm_guest_cpu_offline(); + kvm_guest_cpu_offline(false); local_irq_restore(flags); return 0; } @@ -622,7 +624,7 @@ static int kvm_cpu_down_prepare(unsigned int cpu) static int kvm_suspend(void) { - kvm_guest_cpu_offline(); + kvm_guest_cpu_offline(false); return 0; } @@ -637,6 +639,20 @@ static struct syscore_ops kvm_syscore_ops = { .resume = kvm_resume, }; +/* + * After a PV feature is registered, the host will keep writing to the + * registered memory location. If the guest happens to shutdown, this memory + * won't be valid. In cases like kexec, in which you install a new kernel, this + * means a random memory location will be kept being written. + */ +#ifdef CONFIG_KEXEC_CORE +static void kvm_crash_shutdown(struct pt_regs *regs) +{ + kvm_guest_cpu_offline(true); + native_machine_crash_shutdown(regs); +} +#endif + static void kvm_flush_tlb_others(const struct cpumask *cpumask, const struct flush_tlb_info *info) { @@ -705,6 +721,10 @@ static void __init kvm_guest_init(void) kvm_guest_cpu_init(); #endif +#ifdef CONFIG_KEXEC_CORE + machine_ops.crash_shutdown = kvm_crash_shutdown; +#endif + register_syscore_ops(&kvm_syscore_ops); /* diff --git a/arch/x86/kernel/kvmclock.c b/arch/x86/kernel/kvmclock.c index cf869de98eec..b825c87c12ef 100644 --- a/arch/x86/kernel/kvmclock.c +++ b/arch/x86/kernel/kvmclock.c @@ -20,7 +20,6 @@ #include #include #include -#include #include static int kvmclock __initdata = 1; @@ -203,23 +202,6 @@ static void kvm_setup_secondary_clock(void) } #endif -/* - * After the clock is registered, the host will keep writing to the - * registered memory location. If the guest happens to shutdown, this memory - * won't be valid. In cases like kexec, in which you install a new kernel, this - * means a random memory location will be kept being written. So before any - * kind of shutdown from our side, we unregister the clock by writing anything - * that does not have the 'enable' bit set in the msr - */ -#ifdef CONFIG_KEXEC_CORE -static void kvm_crash_shutdown(struct pt_regs *regs) -{ - native_write_msr(msr_kvm_system_time, 0, 0); - kvm_disable_steal_time(); - native_machine_crash_shutdown(regs); -} -#endif - void kvmclock_disable(void) { native_write_msr(msr_kvm_system_time, 0, 0); @@ -349,9 +331,6 @@ void __init kvmclock_init(void) #endif x86_platform.save_sched_clock_state = kvm_save_sched_clock_state; x86_platform.restore_sched_clock_state = kvm_restore_sched_clock_state; -#ifdef CONFIG_KEXEC_CORE - machine_ops.crash_shutdown = kvm_crash_shutdown; -#endif kvm_get_preset_lpj(); /*