From patchwork Thu Jan 30 13:25:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 11357981 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 890C013B4 for ; Thu, 30 Jan 2020 13:26:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 65CC4217BA for ; Thu, 30 Jan 2020 13:26:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580390784; bh=sU3BN8Mr1a6hHJBH+fD0D7nFUL2EjE2fR14sj2cpogk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=atFICeCnfn3IfOX8mFAG39XjS60OBG92pxL8BmDi7dTma2DUOoxLP2C/3PUesLLEm Ae2libO1fnUkvwkXodOR+48IQ3gd43Peg9hQwx4qj01OMeRkTJHP7rtTNmblB5/S+Q 8e2CC8b+k9SZohXvSJE4C4b4D86aYLrNK5l6xvtI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727412AbgA3N0X (ORCPT ); Thu, 30 Jan 2020 08:26:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:45912 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727388AbgA3N0R (ORCPT ); Thu, 30 Jan 2020 08:26:17 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6313C2253D; Thu, 30 Jan 2020 13:26:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1580390776; bh=sU3BN8Mr1a6hHJBH+fD0D7nFUL2EjE2fR14sj2cpogk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RQE5L7PHLSJdraQXk9r6p2fkp+0+sjJEipYB0nxWtgDIDuWzS+cx1b6b9rlmAsLMK 8o3AY8vMkLO8R5LKEc4U7L0oAPIwP9WmCIpSVGRJK/CtEuyWFdqvvhf4GQhJKjphmm 0k6rSKZrjeaw9totwXTrFkvBIjMGl+fjDMrMUtEc= Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ix9pm-002BmW-N0; Thu, 30 Jan 2020 13:26:14 +0000 From: Marc Zyngier To: Paolo Bonzini Cc: Alexandru Elisei , Andrew Jones , Andrew Murray , Beata Michalska , Christoffer Dall , Eric Auger , Gavin Shan , Haibin Wang , James Morse , Mark Brown , Mark Rutland , Russell King , Shannon Zhao , Steven Price , Will Deacon , YueHaibing , Zenghui Yu , Julien Thierry , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Subject: [PATCH 07/23] KVM: arm/arm64: Re-check VMA on detecting a poisoned page Date: Thu, 30 Jan 2020 13:25:42 +0000 Message-Id: <20200130132558.10201-8-maz@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200130132558.10201-1-maz@kernel.org> References: <20200130132558.10201-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: pbonzini@redhat.com, alexandru.elisei@arm.com, drjones@redhat.com, andrew.murray@arm.com, beata.michalska@linaro.org, christoffer.dall@arm.com, eric.auger@redhat.com, gshan@redhat.com, wanghaibin.wang@huawei.com, james.morse@arm.com, broonie@kernel.org, mark.rutland@arm.com, rmk+kernel@armlinux.org.uk, shannon.zhao@linux.alibaba.com, steven.price@arm.com, will@kernel.org, yuehaibing@huawei.com, yuzenghui@huawei.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: James Morse When we check for a poisoned page, we use the VMA to tell userspace about the looming disaster. But we pass a pointer to this VMA after having released the mmap_sem, which isn't a good idea. Instead, stash the shift value that goes with this pfn while we are holding the mmap_sem. Reported-by: Marc Zyngier Signed-off-by: James Morse Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Link: https://lore.kernel.org/r/20191211165651.7889-3-maz@kernel.org Link: https://lore.kernel.org/r/20191217123809.197392-1-james.morse@arm.com --- virt/kvm/arm/mmu.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/virt/kvm/arm/mmu.c b/virt/kvm/arm/mmu.c index 0b32a904a1bb..e3ad95013192 100644 --- a/virt/kvm/arm/mmu.c +++ b/virt/kvm/arm/mmu.c @@ -1596,16 +1596,8 @@ static void invalidate_icache_guest_page(kvm_pfn_t pfn, unsigned long size) __invalidate_icache_guest_page(pfn, size); } -static void kvm_send_hwpoison_signal(unsigned long address, - struct vm_area_struct *vma) +static void kvm_send_hwpoison_signal(unsigned long address, short lsb) { - short lsb; - - if (is_vm_hugetlb_page(vma)) - lsb = huge_page_shift(hstate_vma(vma)); - else - lsb = PAGE_SHIFT; - send_sig_mceerr(BUS_MCEERR_AR, (void __user *)address, lsb, current); } @@ -1678,6 +1670,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, struct kvm *kvm = vcpu->kvm; struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; struct vm_area_struct *vma; + short vma_shift; kvm_pfn_t pfn; pgprot_t mem_type = PAGE_S2; bool logging_active = memslot_is_logging(memslot); @@ -1701,7 +1694,12 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, return -EFAULT; } - vma_pagesize = vma_kernel_pagesize(vma); + if (is_vm_hugetlb_page(vma)) + vma_shift = huge_page_shift(hstate_vma(vma)); + else + vma_shift = PAGE_SHIFT; + + vma_pagesize = 1ULL << vma_shift; if (logging_active || (vma->vm_flags & VM_PFNMAP) || !fault_supports_stage2_huge_mapping(memslot, hva, vma_pagesize)) { @@ -1741,7 +1739,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writable); if (pfn == KVM_PFN_ERR_HWPOISON) { - kvm_send_hwpoison_signal(hva, vma); + kvm_send_hwpoison_signal(hva, vma_shift); return 0; } if (is_error_noslot_pfn(pfn))