From nobody Wed May 15 16:18:16 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1601026858; cv=none; d=zohomail.com; s=zohoarc; b=ZvlUntk62+xBXsr5XMnQbv09XndYtaBj9V3ASWVmhRBefyXIXeF5R9et9Qq/xXXw2fLRnNMvjJyGA6wkB4yi8BtAZjaCPEcHdZNHnGfXvv/5xKm0LbNlv11sksFMjgu6NuKXNMQUmyMycTJggE/sFJpiaK+ZkW21lg1pcH614IQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1601026858; h=Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To; bh=YT+LnGbzatQFip0onrkdVdTJfQlj90puF2mcxQdogn8=; b=PAqWrZ0FcqaXVV2CuXjzyhQEn4ZIWlnnSuyyPmxrX6/tlBlNp/vDOqmbLTfHMRZlS/4lFQCb9bF76gMOvea+Sfz0cNrmHiNSNp4LlrP4GHrfNp0dvE+/GFePT4MuhWtomaxU44iFJrECu/XysMMD6PCLCJyj4zkm+C02b5uzbdg= ARC-Authentication-Results: i=1; mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1601026858289468.1973435835205; Fri, 25 Sep 2020 02:40:58 -0700 (PDT) Received: from localhost ([::1]:38994 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLkDo-0001mp-OI for importer@patchew.org; Fri, 25 Sep 2020 05:40:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33260) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kLk9S-0000OD-1a for qemu-devel@nongnu.org; Fri, 25 Sep 2020 05:36:26 -0400 Received: from foss.arm.com ([217.140.110.172]:32882) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLk9P-0002Qm-Q1 for qemu-devel@nongnu.org; Fri, 25 Sep 2020 05:36:25 -0400 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 8D77011B3; Fri, 25 Sep 2020 02:36:22 -0700 (PDT) Received: from e112269-lin.arm.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2EAD83F718; Fri, 25 Sep 2020 02:36:20 -0700 (PDT) From: Steven Price To: Catalin Marinas , Marc Zyngier , Will Deacon Subject: [PATCH v3 1/2] arm64: kvm: Save/restore MTE registers Date: Fri, 25 Sep 2020 10:36:06 +0100 Message-Id: <20200925093607.3051-2-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200925093607.3051-1-steven.price@arm.com> References: <20200925093607.3051-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=217.140.110.172; envelope-from=steven.price@arm.com; helo=foss.arm.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/25 05:36:20 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Peter Maydell , "Dr. David Alan Gilbert" , Haibo Xu , Suzuki K Poulose , qemu-devel@nongnu.org, Dave Martin , Juan Quintela , Richard Henderson , linux-kernel@vger.kernel.org, Steven Price , James Morse , Julien Thierry , Thomas Gleixner , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" Define the new system registers that MTE introduces and context switch them. The MTE feature is still hidden from the ID register as it isn't supported in a VM yet. Signed-off-by: Steven Price Reviewed-by: Andrew Jones --- arch/arm64/include/asm/kvm_host.h | 4 ++++ arch/arm64/include/asm/sysreg.h | 3 ++- arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h | 14 ++++++++++++++ arch/arm64/kvm/sys_regs.c | 14 ++++++++++---- 4 files changed, 30 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm= _host.h index e52c927aade5..4f4360dd149e 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -126,6 +126,8 @@ enum vcpu_sysreg { SCTLR_EL1, /* System Control Register */ ACTLR_EL1, /* Auxiliary Control Register */ CPACR_EL1, /* Coprocessor Access Control */ + RGSR_EL1, /* Random Allocation Tag Seed Register */ + GCR_EL1, /* Tag Control Register */ ZCR_EL1, /* SVE Control */ TTBR0_EL1, /* Translation Table Base Register 0 */ TTBR1_EL1, /* Translation Table Base Register 1 */ @@ -142,6 +144,8 @@ enum vcpu_sysreg { TPIDR_EL1, /* Thread ID, Privileged */ AMAIR_EL1, /* Aux Memory Attribute Indirection Register */ CNTKCTL_EL1, /* Timer Control Register (EL1) */ + TFSRE0_EL1, /* Tag Fault Status Register (EL0) */ + TFSR_EL1, /* Tag Fault Stauts Register (EL1) */ PAR_EL1, /* Physical Address Register */ MDSCR_EL1, /* Monitor Debug System Control Register */ MDCCINT_EL1, /* Monitor Debug Comms Channel Interrupt Enable Reg */ diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysre= g.h index 52eefe2f7d95..cd60677551b7 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -563,7 +563,8 @@ #define SCTLR_ELx_M (BIT(0)) =20 #define SCTLR_ELx_FLAGS (SCTLR_ELx_M | SCTLR_ELx_A | SCTLR_ELx_C | \ - SCTLR_ELx_SA | SCTLR_ELx_I | SCTLR_ELx_IESB) + SCTLR_ELx_SA | SCTLR_ELx_I | SCTLR_ELx_IESB | \ + SCTLR_ELx_ITFSB) =20 /* SCTLR_EL2 specific flags. */ #define SCTLR_EL2_RES1 ((BIT(4)) | (BIT(5)) | (BIT(11)) | (BIT(16)) | \ diff --git a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h b/arch/arm64/kvm/hy= p/include/hyp/sysreg-sr.h index 7a986030145f..a124ffa49ba3 100644 --- a/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/sysreg-sr.h @@ -18,6 +18,11 @@ static inline void __sysreg_save_common_state(struct kvm_cpu_context *ctxt) { ctxt_sys_reg(ctxt, MDSCR_EL1) =3D read_sysreg(mdscr_el1); + if (system_supports_mte()) { + ctxt_sys_reg(ctxt, RGSR_EL1) =3D read_sysreg_s(SYS_RGSR_EL1); + ctxt_sys_reg(ctxt, GCR_EL1) =3D read_sysreg_s(SYS_GCR_EL1); + ctxt_sys_reg(ctxt, TFSRE0_EL1) =3D read_sysreg_s(SYS_TFSRE0_EL1); + } } =20 static inline void __sysreg_save_user_state(struct kvm_cpu_context *ctxt) @@ -45,6 +50,8 @@ static inline void __sysreg_save_el1_state(struct kvm_cpu= _context *ctxt) ctxt_sys_reg(ctxt, CNTKCTL_EL1) =3D read_sysreg_el1(SYS_CNTKCTL); ctxt_sys_reg(ctxt, PAR_EL1) =3D read_sysreg(par_el1); ctxt_sys_reg(ctxt, TPIDR_EL1) =3D read_sysreg(tpidr_el1); + if (system_supports_mte()) + ctxt_sys_reg(ctxt, TFSR_EL1) =3D read_sysreg_el1(SYS_TFSR); =20 ctxt_sys_reg(ctxt, SP_EL1) =3D read_sysreg(sp_el1); ctxt_sys_reg(ctxt, ELR_EL1) =3D read_sysreg_el1(SYS_ELR); @@ -63,6 +70,11 @@ static inline void __sysreg_save_el2_return_state(struct= kvm_cpu_context *ctxt) static inline void __sysreg_restore_common_state(struct kvm_cpu_context *c= txt) { write_sysreg(ctxt_sys_reg(ctxt, MDSCR_EL1), mdscr_el1); + if (system_supports_mte()) { + write_sysreg_s(ctxt_sys_reg(ctxt, RGSR_EL1), SYS_RGSR_EL1); + write_sysreg_s(ctxt_sys_reg(ctxt, GCR_EL1), SYS_GCR_EL1); + write_sysreg_s(ctxt_sys_reg(ctxt, TFSRE0_EL1), SYS_TFSRE0_EL1); + } } =20 static inline void __sysreg_restore_user_state(struct kvm_cpu_context *ctx= t) @@ -106,6 +118,8 @@ static inline void __sysreg_restore_el1_state(struct kv= m_cpu_context *ctxt) write_sysreg_el1(ctxt_sys_reg(ctxt, CNTKCTL_EL1), SYS_CNTKCTL); write_sysreg(ctxt_sys_reg(ctxt, PAR_EL1), par_el1); write_sysreg(ctxt_sys_reg(ctxt, TPIDR_EL1), tpidr_el1); + if (system_supports_mte()) + write_sysreg_el1(ctxt_sys_reg(ctxt, TFSR_EL1), SYS_TFSR); =20 if (!has_vhe() && cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT) && diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 379f4969d0bd..a655f172b5ad 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1391,6 +1391,12 @@ static bool access_mte_regs(struct kvm_vcpu *vcpu, s= truct sys_reg_params *p, return false; } =20 +static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + return REG_HIDDEN_USER | REG_HIDDEN_GUEST; +} + /* sys_reg_desc initialiser for known cpufeature ID registers */ #define ID_SANITISED(name) { \ SYS_DESC(SYS_##name), \ @@ -1557,8 +1563,8 @@ static const struct sys_reg_desc sys_reg_descs[] =3D { { SYS_DESC(SYS_ACTLR_EL1), access_actlr, reset_actlr, ACTLR_EL1 }, { SYS_DESC(SYS_CPACR_EL1), NULL, reset_val, CPACR_EL1, 0 }, =20 - { SYS_DESC(SYS_RGSR_EL1), access_mte_regs }, - { SYS_DESC(SYS_GCR_EL1), access_mte_regs }, + { SYS_DESC(SYS_RGSR_EL1), access_mte_regs, reset_unknown, RGSR_EL1, .visi= bility =3D mte_visibility }, + { SYS_DESC(SYS_GCR_EL1), access_mte_regs, reset_unknown, GCR_EL1, .visibi= lity =3D mte_visibility }, =20 { SYS_DESC(SYS_ZCR_EL1), NULL, reset_val, ZCR_EL1, 0, .visibility =3D sve= _visibility }, { SYS_DESC(SYS_TTBR0_EL1), access_vm_reg, reset_unknown, TTBR0_EL1 }, @@ -1584,8 +1590,8 @@ static const struct sys_reg_desc sys_reg_descs[] =3D { { SYS_DESC(SYS_ERXMISC0_EL1), trap_raz_wi }, { SYS_DESC(SYS_ERXMISC1_EL1), trap_raz_wi }, =20 - { SYS_DESC(SYS_TFSR_EL1), access_mte_regs }, - { SYS_DESC(SYS_TFSRE0_EL1), access_mte_regs }, + { SYS_DESC(SYS_TFSR_EL1), access_mte_regs, reset_unknown, TFSR_EL1, .visi= bility =3D mte_visibility }, + { SYS_DESC(SYS_TFSRE0_EL1), access_mte_regs, reset_unknown, TFSRE0_EL1, .= visibility =3D mte_visibility }, =20 { SYS_DESC(SYS_FAR_EL1), access_vm_reg, reset_unknown, FAR_EL1 }, { SYS_DESC(SYS_PAR_EL1), NULL, reset_unknown, PAR_EL1 }, --=20 2.20.1 From nobody Wed May 15 16:18:16 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; 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Fri, 25 Sep 2020 02:41:05 -0700 (PDT) Received: from localhost ([::1]:39012 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLkDv-0001nG-Oa for importer@patchew.org; Fri, 25 Sep 2020 05:41:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33278) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kLk9U-0000PG-16 for qemu-devel@nongnu.org; Fri, 25 Sep 2020 05:36:28 -0400 Received: from foss.arm.com ([217.140.110.172]:32908) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kLk9R-0002R0-V8 for qemu-devel@nongnu.org; Fri, 25 Sep 2020 05:36:27 -0400 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 2FED61045; Fri, 25 Sep 2020 02:36:25 -0700 (PDT) Received: from e112269-lin.arm.com (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C4B1C3F718; Fri, 25 Sep 2020 02:36:22 -0700 (PDT) From: Steven Price To: Catalin Marinas , Marc Zyngier , Will Deacon Subject: [PATCH v3 2/2] arm64: kvm: Introduce MTE VCPU feature Date: Fri, 25 Sep 2020 10:36:07 +0100 Message-Id: <20200925093607.3051-3-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200925093607.3051-1-steven.price@arm.com> References: <20200925093607.3051-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=217.140.110.172; envelope-from=steven.price@arm.com; helo=foss.arm.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/25 05:36:20 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Peter Maydell , "Dr. David Alan Gilbert" , Haibo Xu , Suzuki K Poulose , qemu-devel@nongnu.org, Dave Martin , Juan Quintela , Richard Henderson , linux-kernel@vger.kernel.org, Steven Price , James Morse , Julien Thierry , Thomas Gleixner , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" Add a new VM feature 'KVM_ARM_CAP_MTE' which enables memory tagging for a VM. This exposes the feature to the guest and automatically tags memory pages touched by the VM as PG_mte_tagged (and clears the tags storage) to ensure that the guest cannot see stale tags, and so that the tags are correctly saved/restored across swap. Signed-off-by: Steven Price Reviewed-by: Andrew Jones --- arch/arm64/include/asm/kvm_emulate.h | 3 +++ arch/arm64/include/asm/kvm_host.h | 3 +++ arch/arm64/kvm/arm.c | 9 +++++++++ arch/arm64/kvm/mmu.c | 15 +++++++++++++++ arch/arm64/kvm/sys_regs.c | 6 +++++- include/uapi/linux/kvm.h | 1 + 6 files changed, 36 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/= kvm_emulate.h index 49a55be2b9a2..4923a566ae6e 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -79,6 +79,9 @@ static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu) if (cpus_have_const_cap(ARM64_MISMATCHED_CACHE_TYPE) || vcpu_el1_is_32bit(vcpu)) vcpu->arch.hcr_el2 |=3D HCR_TID2; + + if (vcpu->kvm->arch.mte_enabled) + vcpu->arch.hcr_el2 |=3D HCR_ATA; } =20 static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm= _host.h index 4f4360dd149e..1379300c1487 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -110,6 +110,9 @@ struct kvm_arch { * supported. */ bool return_nisv_io_abort_to_user; + + /* Memory Tagging Extension enabled for the guest */ + bool mte_enabled; }; =20 struct kvm_vcpu_fault_info { diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 46dc3d75cf13..624edca0a1fa 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -87,6 +87,12 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm, r =3D 0; kvm->arch.return_nisv_io_abort_to_user =3D true; break; + case KVM_CAP_ARM_MTE: + if (!system_supports_mte() || kvm->created_vcpus) + return -EINVAL; + r =3D 0; + kvm->arch.mte_enabled =3D true; + break; default: r =3D -EINVAL; break; @@ -206,6 +212,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long = ext) */ r =3D 1; break; + case KVM_CAP_ARM_MTE: + r =3D system_supports_mte(); + break; default: r =3D kvm_arch_vm_ioctl_check_extension(kvm, ext); break; diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index ba00bcc0c884..befb9e1f0aa6 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1949,6 +1949,21 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phy= s_addr_t fault_ipa, if (vma_pagesize =3D=3D PAGE_SIZE && !force_pte) vma_pagesize =3D transparent_hugepage_adjust(memslot, hva, &pfn, &fault_ipa); + if (system_supports_mte() && kvm->arch.mte_enabled && pfn_valid(pfn)) { + /* + * VM will be able to see the page's tags, so we must ensure + * they have been initialised. + */ + struct page *page =3D pfn_to_page(pfn); + long i, nr_pages =3D compound_nr(page); + + /* if PG_mte_tagged is set, tags have already been initialised */ + for (i =3D 0; i < nr_pages; i++, page++) { + if (!test_and_set_bit(PG_mte_tagged, &page->flags)) + mte_clear_page_tags(page_address(page)); + } + } + if (writable) kvm_set_pfn_dirty(pfn); =20 diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index a655f172b5ad..5010a47152b4 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1132,7 +1132,8 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, val &=3D ~(0xfUL << ID_AA64PFR0_SVE_SHIFT); val &=3D ~(0xfUL << ID_AA64PFR0_AMU_SHIFT); } else if (id =3D=3D SYS_ID_AA64PFR1_EL1) { - val &=3D ~(0xfUL << ID_AA64PFR1_MTE_SHIFT); + if (!vcpu->kvm->arch.mte_enabled) + val &=3D ~(0xfUL << ID_AA64PFR1_MTE_SHIFT); } else if (id =3D=3D SYS_ID_AA64ISAR1_EL1 && !vcpu_has_ptrauth(vcpu)) { val &=3D ~((0xfUL << ID_AA64ISAR1_APA_SHIFT) | (0xfUL << ID_AA64ISAR1_API_SHIFT) | @@ -1394,6 +1395,9 @@ static bool access_mte_regs(struct kvm_vcpu *vcpu, st= ruct sys_reg_params *p, static unsigned int mte_visibility(const struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd) { + if (vcpu->kvm->arch.mte_enabled) + return 0; + return REG_HIDDEN_USER | REG_HIDDEN_GUEST; } =20 diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index f6d86033c4fa..87678ed82ab4 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -1035,6 +1035,7 @@ struct kvm_ppc_resize_hpt { #define KVM_CAP_LAST_CPU 184 #define KVM_CAP_SMALLER_MAXPHYADDR 185 #define KVM_CAP_S390_DIAG318 186 +#define KVM_CAP_ARM_MTE 188 =20 #ifdef KVM_CAP_IRQ_ROUTING =20 --=20 2.20.1