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 Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7208DC433FE for ; Sat, 14 May 2022 10:09:12 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 214F34B172; Sat, 14 May 2022 06:09:12 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@google.com Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2X-hxRb5Zfp2; Sat, 14 May 2022 06:09:10 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 419AE4B265; Sat, 14 May 2022 06:08:57 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id CAD5349EF6 for ; Fri, 13 May 2022 16:28:53 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id CZwFKoKa+Ia0 for ; Fri, 13 May 2022 16:28:52 -0400 (EDT) Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id B81DA49F46 for ; Fri, 13 May 2022 16:28:52 -0400 (EDT) Received: by mail-pl1-f202.google.com with SMTP id s2-20020a17090302c200b00158ea215fa2so4865286plk.3 for ; Fri, 13 May 2022 13:28:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=lgtnhvy7+1BCZ2eFCe2s9WzklomHzRT131Cc2B3t8Gs=; b=nlPBmMlvFaiiHIxBMCrdBviz09aO2UJ3P4BQKD5zdeS25QzxpRCDfJttzo3xnUZ3Zs Woc893zPTgCcikXTcx871Qn4AldyKgfNp5bhRfkB5aTHiWuKhD/2hlwkDGQG+bdtSfCJ htizOAEaEMSFrbCyY8nQEcTm+sBtLwKgpm0M1SnltyfsLkatXQvqOzXVLhssiby5a9uA nCGOh5FXrAGdfj5Gi01e06xx6gcqb9lxybyoHb0Ra8A20IDSft8W4ZT923y2E/L1w1Jn 8JQ+rvf4CFTSsJ1aFmJndTHh1Mk5kLvigrQojP9i4rbS7D9XblX3FX2aqFNyzr3FsSV+ 9BmA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=lgtnhvy7+1BCZ2eFCe2s9WzklomHzRT131Cc2B3t8Gs=; b=pZusD0IOm3CFTX4hiCbTaL3ea8DejUnRaLNloYGND5tF77WFdNuVbwyO8xHz5PAOXB vE8ZTr/Y2hA9kHS2xOZQCCT4SJSnujXNMrt9c3Ch/WSStjJB5XZVJTPKzqlBt5KX9x9Y HbtPmIsxicn4C7OMJ+nTOrz9cTBCI7YPoBRAn1txT9SeqpWe5q5YidEfIxqP7qCCxYYd tmoUCbJP6OK2LFA0hnnN1wouFWaOV+PQNwzG64PQdyGHBQIf6WmH9pd1LommLUAz5SvM oyM1VDDcv7ig0i2galM4jfEAa56e2DlbPYQRDgdROrT3w7/mS5dqZDqM7q8GiGLJ3gyS 64Tg== X-Gm-Message-State: AOAM532jfhiGinz9wmIvFylmtnO5tC01Yl4ax4A/XkhZrUhiqqzueMx5 +efvpV2WbuWhOn1D/r72yWlvR4ixYKHxgA== X-Google-Smtp-Source: ABdhPJwTCP7I8XFt//8SoYQKhPgP4tZAxj29bs/HtPYVJcnz6pLypD536V2k28Bo91JrBLRkEwYnsf8a77QRUg== X-Received: from dmatlack-heavy.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:19cd]) (user=dmatlack job=sendgmr) by 2002:a17:90b:1251:b0:1d7:f7ae:9f1 with SMTP id gx17-20020a17090b125100b001d7f7ae09f1mr17935511pjb.65.1652473731863; Fri, 13 May 2022 13:28:51 -0700 (PDT) Date: Fri, 13 May 2022 20:28:10 +0000 In-Reply-To: <20220513202819.829591-1-dmatlack@google.com> Message-Id: <20220513202819.829591-13-dmatlack@google.com> Mime-Version: 1.0 References: <20220513202819.829591-1-dmatlack@google.com> X-Mailer: git-send-email 2.36.0.550.gb090851708-goog Subject: [PATCH v5 12/21] KVM: x86/mmu: Allow NULL @vcpu in kvm_mmu_find_shadow_page() From: David Matlack To: Paolo Bonzini X-Mailman-Approved-At: Sat, 14 May 2022 06:08:54 -0400 Cc: Albert Ou , "open list:KERNEL VIRTUAL MACHINE FOR MIPS \(KVM/mips\)" , Marc Zyngier , Huacai Chen , Lai Jiangshan , "open list:KERNEL VIRTUAL MACHINE FOR MIPS \(KVM/mips\)" , David Matlack , Aleksandar Markovic , Palmer Dabbelt , "open list:KERNEL VIRTUAL MACHINE FOR RISC-V \(KVM/riscv\)" , Paul Walmsley , Ben Gardon , maciej.szmigiero@oracle.com, "moderated list:KERNEL VIRTUAL MACHINE FOR ARM64 \(KVM/arm64\)" , Peter Feiner X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Allow @vcpu to be NULL in kvm_mmu_find_shadow_page() (and its only caller __kvm_mmu_get_shadow_page()). @vcpu is only required to sync indirect shadow pages, so it's safe to pass in NULL when looking up direct shadow pages. This will be used for doing eager page splitting, which allocates direct shadow pages from the context of a VM ioctl without access to a vCPU pointer. Signed-off-by: David Matlack --- arch/x86/kvm/mmu/mmu.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index cf27c5de9dc0..bc66029d837f 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -1850,6 +1850,7 @@ static int kvm_sync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp, if (ret < 0) kvm_mmu_prepare_zap_page(vcpu->kvm, sp, invalid_list); + return ret; } @@ -2001,6 +2002,7 @@ static void clear_sp_write_flooding_count(u64 *spte) __clear_sp_write_flooding_count(sptep_to_sp(spte)); } +/* Note, @vcpu may be NULL if @role.direct is true. */ static struct kvm_mmu_page *kvm_mmu_find_shadow_page(struct kvm *kvm, struct kvm_vcpu *vcpu, gfn_t gfn, @@ -2039,6 +2041,16 @@ static struct kvm_mmu_page *kvm_mmu_find_shadow_page(struct kvm *kvm, goto out; if (sp->unsync) { + /* + * A vCPU pointer should always be provided when finding + * indirect shadow pages, as that shadow page may + * already exist and need to be synced using the vCPU + * pointer. Direct shadow pages are never unsync and + * thus do not require a vCPU pointer. + */ + if (KVM_BUG_ON(!vcpu, kvm)) + break; + /* * The page is good, but is stale. kvm_sync_page does * get the latest guest state, but (unlike mmu_unsync_children) @@ -2116,6 +2128,7 @@ static struct kvm_mmu_page *kvm_mmu_alloc_shadow_page(struct kvm *kvm, return sp; } +/* Note, @vcpu may be NULL if @role.direct is true. */ static struct kvm_mmu_page *__kvm_mmu_get_shadow_page(struct kvm *kvm, struct kvm_vcpu *vcpu, struct shadow_page_caches *caches, -- 2.36.0.550.gb090851708-goog _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm