From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id A8D3B3D902C for ; Wed, 18 Mar 2026 13:43:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773841411; cv=none; b=KY0eZtzyaf3neBj75Tpre680Ny1gc1YH4EOAIkZZWnEjxeLoBJyj3ZeJbYMqfttP7Io5TeinW/ALExHq/CDWu5AsSJVz7Mxg/ErKWiO0gDvmhreiSZVb+aGv8gViwmEOOnu8FkUFOkOjKecvM1oLWs8vZxPi2g23wwhtw7OLVXU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773841411; c=relaxed/simple; bh=0CHweL7Qoq/6T3NeuOTeEVI0sVTLwvv7YbW2pvbrx7k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UhxCl16yY545+6waupcnsz1YqU/xfvgzF43d+F+gX718XRHwCDp6cHIQe7YQX0Jd3r014/CkwGS1QQ2DUEZJnRkWGrQA/0J+KM/ISnnW8Fb7FEN5Oy6LnN+BeBE0pUidSEGsEeGmF6M9SkDeZ0rNCuJpN0T6aNoChqrj4xZJ2y4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E5A1E1BF7; Wed, 18 Mar 2026 06:43:22 -0700 (PDT) Received: from e124191.cambridge.arm.com (e124191.cambridge.arm.com [10.1.197.45]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8BD9C3F73B; Wed, 18 Mar 2026 06:43:27 -0700 (PDT) Date: Wed, 18 Mar 2026 13:43:22 +0000 From: Joey Gouly To: Marc Zyngier Cc: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Will Deacon , Quentin Perret Subject: Re: [PATCH 04/17] KVM: arm64: Replace fault_is_perm with a helper Message-ID: <20260318134322.GA3915656@e124191.cambridge.arm.com> References: <20260316175451.1866175-1-maz@kernel.org> <20260316175451.1866175-5-maz@kernel.org> Precedence: bulk X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260316175451.1866175-5-maz@kernel.org> On Mon, Mar 16, 2026 at 05:54:37PM +0000, Marc Zyngier wrote: > Carrying a boolean to indicate that a given fault is slightly odd, ESR_ELx_FSC_SLIGHTLY_ODD :D (probably should be "that a given fault is a permission fault is..") Reviewed-by: Joey Gouly > as this is a property of the fault itself, and we'd better avoid > duplicating state. > > For this purpose, introduce a kvm_s2_fault_is_perm() predicate that > can take a fault descriptor as a parameter. fault_is_perm is therefore > dropped from kvm_s2_fault. > > Signed-off-by: Marc Zyngier > --- > arch/arm64/kvm/mmu.c | 17 ++++++++++------- > 1 file changed, 10 insertions(+), 7 deletions(-) > > diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c > index 2a7128b8dd14f..1b32f2e6c3e61 100644 > --- a/arch/arm64/kvm/mmu.c > +++ b/arch/arm64/kvm/mmu.c > @@ -1711,8 +1711,6 @@ static short kvm_s2_resolve_vma_size(const struct kvm_s2_fault_desc *s2fd, > } > > struct kvm_s2_fault { > - bool fault_is_perm; > - > bool write_fault; > bool exec_fault; > bool writable; > @@ -1732,6 +1730,11 @@ struct kvm_s2_fault { > vm_flags_t vm_flags; > }; > > +static bool kvm_s2_fault_is_perm(const struct kvm_s2_fault_desc *s2fd) > +{ > + return kvm_vcpu_trap_is_permission_fault(s2fd->vcpu); > +} > + > static int kvm_s2_fault_get_vma_info(const struct kvm_s2_fault_desc *s2fd, > struct kvm_s2_fault *fault) > { > @@ -1888,7 +1891,7 @@ static int kvm_s2_fault_compute_prot(const struct kvm_s2_fault_desc *s2fd, > if (s2fd->nested) > adjust_nested_exec_perms(kvm, s2fd->nested, &fault->prot); > > - if (!fault->fault_is_perm && !fault->s2_force_noncacheable && kvm_has_mte(kvm)) { > + if (!kvm_s2_fault_is_perm(s2fd) && !fault->s2_force_noncacheable && kvm_has_mte(kvm)) { > /* Check the VMM hasn't introduced a new disallowed VMA */ > if (!fault->mte_allowed) > return -EFAULT; > @@ -1905,6 +1908,7 @@ static phys_addr_t get_ipa(const struct kvm_s2_fault *fault) > static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, > struct kvm_s2_fault *fault, void *memcache) > { > + bool fault_is_perm = kvm_s2_fault_is_perm(s2fd); > struct kvm *kvm = s2fd->vcpu->kvm; > struct kvm_pgtable *pgt; > int ret; > @@ -1922,7 +1926,7 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, > */ > if (fault->vma_pagesize == PAGE_SIZE && > !(fault->force_pte || fault->s2_force_noncacheable)) { > - if (fault->fault_is_perm && fault->fault_granule > PAGE_SIZE) { > + if (fault_is_perm && fault->fault_granule > PAGE_SIZE) { > fault->vma_pagesize = fault->fault_granule; > } else { > fault->vma_pagesize = transparent_hugepage_adjust(kvm, s2fd->memslot, > @@ -1936,7 +1940,7 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, > } > } > > - if (!fault->fault_is_perm && !fault->s2_force_noncacheable && kvm_has_mte(kvm)) > + if (!fault_is_perm && !fault->s2_force_noncacheable && kvm_has_mte(kvm)) > sanitise_mte_tags(kvm, fault->pfn, fault->vma_pagesize); > > /* > @@ -1944,7 +1948,7 @@ static int kvm_s2_fault_map(const struct kvm_s2_fault_desc *s2fd, > * permissions only if fault->vma_pagesize equals fault->fault_granule. Otherwise, > * kvm_pgtable_stage2_map() should be called to change block size. > */ > - if (fault->fault_is_perm && fault->vma_pagesize == fault->fault_granule) { > + if (fault_is_perm && fault->vma_pagesize == fault->fault_granule) { > /* > * Drop the SW bits in favour of those stored in the > * PTE, which will be preserved. > @@ -1977,7 +1981,6 @@ static int user_mem_abort(const struct kvm_s2_fault_desc *s2fd) > bool write_fault = kvm_is_write_fault(s2fd->vcpu); > bool logging_active = memslot_is_logging(s2fd->memslot); > struct kvm_s2_fault fault = { > - .fault_is_perm = perm_fault, > .logging_active = logging_active, > .force_pte = logging_active, > .prot = KVM_PGTABLE_PROT_R, > -- > 2.47.3 >