From patchwork Wed Dec 19 18:03:28 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 10737907 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 41DB06C5 for ; Wed, 19 Dec 2018 18:07:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3198E2B6D4 for ; Wed, 19 Dec 2018 18:07:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 25D1E2B7A7; Wed, 19 Dec 2018 18:07:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id B8EF92B6D4 for ; Wed, 19 Dec 2018 18:07:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Kr89QXcWCPMzrXj3ddXFQPLZC5/HyCjbf2GPOPVJp1A=; b=Y9hnBHW65q4N8L 2m6PkZxipB/BMgJg2kBTGIqPzud0DBh/qIceSnLCVSsDvrxr+fARt1IzOPnpwI0DtTB4R4W3Sg90O SzjAq9n/c6OK7Bqg/FKyVOXauw/CSpz6U98jBo1jbcZA3G7dbOK0FHLUd3LXC6fbk56/i8V91zlyQ f/u/H7ampA5gWGU4VBVRlfNxjf2Ae4uBOCHYYM/N/vjDpEzUCadgZM4fmBiHExysJXe5LMWXwk94x M4ph/b4VrSnslkmfxk3e+zAFPBfB/yUgsY4cvmfZIWHGVRMPJswDZdq2ZECKWYJeDaTL1SupBxj3F FonCXiXCwG+Ln7jm9YuA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gZgFC-0000vS-Su; Wed, 19 Dec 2018 18:06:54 +0000 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70] helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gZgCx-0005vR-Nr for linux-arm-kernel@lists.infradead.org; Wed, 19 Dec 2018 18:04:40 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0CEF715AB; Wed, 19 Dec 2018 10:04:29 -0800 (PST) Received: from filthy-habits.cambridge.arm.com (filthy-habits.cambridge.arm.com [10.1.196.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8243A3F675; Wed, 19 Dec 2018 10:04:26 -0800 (PST) From: Marc Zyngier To: Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= Subject: [PATCH 07/28] KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault Date: Wed, 19 Dec 2018 18:03:28 +0000 Message-Id: <20181219180349.242681-8-marc.zyngier@arm.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181219180349.242681-1-marc.zyngier@arm.com> References: <20181219180349.242681-1-marc.zyngier@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181219_100435_911066_E67C430B X-CRM114-Status: GOOD ( 16.91 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Punit Agrawal , kvm@vger.kernel.org, Julien Thierry , "Gustavo A . R . Silva" , Will Deacon , Christoffer Dall , linux-arm-kernel@lists.infradead.org, punitagrawal@gmail.com, =?utf-8?q?Ale?= =?utf-8?q?x_Benn=C3=A9e?= , kvmarm@lists.cs.columbia.edu, Suzuki Poulose , Lukas Braun Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Punit Agrawal Stage 2 fault handler marks a page as executable if it is handling an execution fault or if it was a permission fault in which case the executable bit needs to be preserved. The logic to decide if the page should be marked executable is duplicated for PMD and PTE entries. To avoid creating another copy when support for PUD hugepages is introduced refactor the code to share the checks needed to mark a page table entry as executable. Signed-off-by: Punit Agrawal Reviewed-by: Suzuki K Poulose Reviewed-by: Christoffer Dall Signed-off-by: Suzuki K Poulose Signed-off-by: Marc Zyngier --- virt/kvm/arm/mmu.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 59595207c5e1..6912529946fb 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1475,7 +1475,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, unsigned long fault_status) { int ret; - bool write_fault, exec_fault, writable, force_pte = false; + bool write_fault, writable, force_pte = false; + bool exec_fault, needs_exec; unsigned long mmu_seq; gfn_t gfn = fault_ipa >> PAGE_SHIFT; struct kvm *kvm = vcpu->kvm; @@ -1598,19 +1599,25 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (exec_fault) invalidate_icache_guest_page(pfn, vma_pagesize); + /* + * If we took an execution fault we have made the + * icache/dcache coherent above and should now let the s2 + * mapping be executable. + * + * Write faults (!exec_fault && FSC_PERM) are orthogonal to + * execute permissions, and we preserve whatever we have. + */ + needs_exec = exec_fault || + (fault_status == FSC_PERM && stage2_is_exec(kvm, fault_ipa)); + if (vma_pagesize == PMD_SIZE) { pmd_t new_pmd = pfn_pmd(pfn, mem_type); new_pmd = pmd_mkhuge(new_pmd); if (writable) new_pmd = kvm_s2pmd_mkwrite(new_pmd); - if (exec_fault) { + if (needs_exec) new_pmd = kvm_s2pmd_mkexec(new_pmd); - } else if (fault_status == FSC_PERM) { - /* Preserve execute if XN was already cleared */ - if (stage2_is_exec(kvm, fault_ipa)) - new_pmd = kvm_s2pmd_mkexec(new_pmd); - } ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd); } else { @@ -1621,13 +1628,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, mark_page_dirty(kvm, gfn); } - if (exec_fault) { + if (needs_exec) new_pte = kvm_s2pte_mkexec(new_pte); - } else if (fault_status == FSC_PERM) { - /* Preserve execute if XN was already cleared */ - if (stage2_is_exec(kvm, fault_ipa)) - new_pte = kvm_s2pte_mkexec(new_pte); - } ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, flags); }