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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5EC81CD5BD1 for ; Mon, 1 Jun 2026 22:28:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=t9kW9wxmbYR0zK6wTk5cssPV12k29fXpKDHVyEt5l6g=; b=xSiar7ZUYmLcGEMWKgazqBFQ5L O9YvLVE9ByvbV6TcltHqEI2tRcxWmWT4L+zbSkcXAoFEjUu6JhYVZrWjlhkMABOdeGO47Udr9rQQE P1WqKTFrLkQoh5UvfFEik+0AP8WPZsFXa+DB8Bg3qgqLrbpaXCe8hdMG7MewnZN296WseSv5tKGEg qIPeSMuaYcu+DR04MtOKi4RSGYIizRq3Gf5Z07PTvbdFub18oCLpfvDh7eK1+433f5QYmBKi4Za5P U3L6hVwEeqfZebgvxrNqI6gXoIZx0dH0gkDwMigC8POoiPdWqySeUYlgRHYyy1IEuPqnk2fPt8fwA OXr2sueg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wUB7L-0000000BwH9-3iMa; Mon, 01 Jun 2026 22:28:19 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wUB7K-0000000BwGq-0xuD for linux-arm-kernel@lists.infradead.org; Mon, 01 Jun 2026 22:28:18 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 54B276001D; Mon, 1 Jun 2026 22:28:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9F3D71F00893; Mon, 1 Jun 2026 22:28:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780352897; bh=t9kW9wxmbYR0zK6wTk5cssPV12k29fXpKDHVyEt5l6g=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=kkEMaOzk11QJr+Q7Sr/AQBjqPi1yH/uZhUKLQJj1zni60iihNwEZy8zCtJ4CboOJd 73A8dNgNWdmoZfGgoE6rFir6mtHM05eSZ5PPzyq4pRHkMzD584vIdBRn9Daain4l8i ntv/VxdH1CXhptzix/FwRz4d/+E138PMtZv3hDF+32WMbjomSSA+GvQo3YBOcnEbgP NWGp297AQqntrIqiUhSp9V5Gtd0xSBbnLcLHpbp1jtlgjk6EawzCHjM4lSIctypMAs gB49wFWNUQ6lDrObYrMIKmdybuUNUaanjBhBRFnAfhiP5Ir0Oyg2ULplrVZEb5qdf3 oyPpwbAZshTgQ== Date: Mon, 1 Jun 2026 15:28:15 -0700 From: Oliver Upton To: Steffen Eiden Cc: kvm@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, Alexander Gordeev , Andreas Grapentin , Arnd Bergmann , Catalin Marinas , Christian Borntraeger , Claudio Imbrenda , David Hildenbrand , Friedrich Welter , Gautam Gala , Hariharan Mari , Heiko Carstens , Hendrik Brueckner , Ilya Leoshkevich , Janosch Frank , Joey Gouly , Marc Zyngier , Nico Boehr , Nina Schoetterl-Glausch , Paolo Bonzini , Suzuki K Poulose , Sven Schnelle , Ulrich Weigand , Vasily Gorbik , Will Deacon , Zenghui Yu Subject: Re: [PATCH v1 09/26] KVM: arm64: Refactor idreg caching into dedicated structure Message-ID: References: <20260529155601.2927240-1-seiden@linux.ibm.com> <20260529155601.2927240-10-seiden@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260529155601.2927240-10-seiden@linux.ibm.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, May 29, 2026 at 05:55:42PM +0200, Steffen Eiden wrote: > +struct kvm_vm_id_regs { > + /* > + * Emulated CPU ID registers per VM > + * (Op0, Op1, CRn, CRm, Op2) of the ID registers to be saved in it > + * is (3, 0, 0, crm, op2), where 1<=crm<8, 0<=op2<8. > + * > + * These emulated idregs are VM-wide, but accessed from the context of a vCPU. > + * Atomic access to multiple idregs are guarded by kvm_arch.config_lock. > + */ > +#define IDREG_IDX(id) (((sys_reg_CRm(id) - 1) << 3) | sys_reg_Op2(id)) > +#define KVM_ARM_ID_REG_NUM (IDREG_IDX(sys_reg(3, 0, 0, 7, 7)) + 1) > + u64 normal[KVM_ARM_ID_REG_NUM]; nit: ftr_reg would be slightly more clear. Thanks, Oliver > + u64 midr_el1; > + u64 revidr_el1; > + u64 aidr_el1; > + u64 ctr_el0; > +}; > + > +static inline u64 *__vm_id_reg(struct kvm_vm_id_regs *id_regs, u32 reg) > { > switch (reg) { > case sys_reg(3, 0, 0, 1, 0) ... sys_reg(3, 0, 0, 7, 7): > - return &ka->id_regs[IDREG_IDX(reg)]; > + return &id_regs->normal[IDREG_IDX(reg)]; > case SYS_CTR_EL0: > - return &ka->ctr_el0; > + return &id_regs->ctr_el0; > case SYS_MIDR_EL1: > - return &ka->midr_el1; > + return &id_regs->midr_el1; > case SYS_REVIDR_EL1: > - return &ka->revidr_el1; > + return &id_regs->revidr_el1; > case SYS_AIDR_EL1: > - return &ka->aidr_el1; > + return &id_regs->aidr_el1; > default: > WARN_ON_ONCE(1); > return NULL; > @@ -1419,7 +1423,7 @@ static inline u64 *__vm_id_reg(struct kvm_arch *ka, u32 reg) > } > > #define kvm_read_vm_id_reg(kvm, reg) \ > - ({ u64 __val = *__vm_id_reg(&(kvm)->arch, reg); __val; }) > + ({ u64 __val = *__vm_id_reg(&(kvm)->arch.id_regs, reg); __val; }) > > void kvm_set_vm_id_reg(struct kvm *kvm, u32 reg, u64 val); > > diff --git a/arch/arm64/kvm/config.c b/arch/arm64/kvm/config.c > index 014fe04daabf..58a439c3ab9c 100644 > --- a/arch/arm64/kvm/config.c > +++ b/arch/arm64/kvm/config.c > @@ -1398,7 +1398,7 @@ void __init check_feature_map(void) > > static bool idreg_feat_match(struct kvm *kvm, const struct reg_bits_to_feat_map *map) > { > - u64 regval = kvm->arch.id_regs[map->regidx]; > + u64 regval = kvm->arch.id_regs.normal[map->regidx]; > u64 regfld = (regval >> map->shift) & GENMASK(map->width - 1, 0); > > if (map->sign) { > diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c > index eb1c10120f9f..94620f142f42 100644 > --- a/arch/arm64/kvm/hyp/nvhe/pkvm.c > +++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c > @@ -343,7 +343,7 @@ static void pkvm_init_features_from_host(struct pkvm_hyp_vm *hyp_vm, const struc > DECLARE_BITMAP(allowed_features, KVM_VCPU_MAX_FEATURES); > > /* CTR_EL0 is always under host control, even for protected VMs. */ > - hyp_vm->kvm.arch.ctr_el0 = host_kvm->arch.ctr_el0; > + hyp_vm->kvm.arch.id_regs.ctr_el0 = host_kvm->arch.id_regs.ctr_el0; > > /* Preserve the vgic model so that GICv3 emulation works */ > hyp_vm->kvm.arch.vgic.vgic_model = host_kvm->arch.vgic.vgic_model; > @@ -358,7 +358,7 @@ static void pkvm_init_features_from_host(struct pkvm_hyp_vm *hyp_vm, const struc > KVM_VCPU_MAX_FEATURES); > > if (test_bit(KVM_ARCH_FLAG_WRITABLE_IMP_ID_REGS, &host_arch_flags)) > - hyp_vm->kvm.arch.midr_el1 = host_kvm->arch.midr_el1; > + hyp_vm->kvm.arch.id_regs.midr_el1 = host_kvm->arch.id_regs.midr_el1; > > return; > } > @@ -493,7 +493,8 @@ static int vm_copy_id_regs(struct pkvm_hyp_vcpu *hyp_vcpu) > if (test_and_set_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags)) > return 0; > > - memcpy(kvm->arch.id_regs, host_kvm->arch.id_regs, sizeof(kvm->arch.id_regs)); > + memcpy(kvm->arch.id_regs.normal, host_kvm->arch.id_regs.normal, > + sizeof(kvm->arch.id_regs.normal)); > > return 0; > } > diff --git a/arch/arm64/kvm/hyp/nvhe/sys_regs.c b/arch/arm64/kvm/hyp/nvhe/sys_regs.c > index b5a0de84ce01..e8d773d38905 100644 > --- a/arch/arm64/kvm/hyp/nvhe/sys_regs.c > +++ b/arch/arm64/kvm/hyp/nvhe/sys_regs.c > @@ -292,7 +292,7 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, > return 0; > > if (reg >= sys_reg(3, 0, 0, 1, 0) && reg <= sys_reg(3, 0, 0, 7, 7)) > - return kvm->arch.id_regs[IDREG_IDX(reg)]; > + return kvm->arch.id_regs.normal[IDREG_IDX(reg)]; > > return 0; > } > @@ -543,7 +543,7 @@ void kvm_init_pvm_id_regs(struct kvm_vcpu *vcpu) > * for protected VMs. > */ > for (r = sys_reg(3, 0, 0, 4, 0); r <= sys_reg(3, 0, 0, 7, 7); r += sys_reg(0, 0, 0, 0, 1)) > - ka->id_regs[IDREG_IDX(r)] = pvm_calc_id_reg(vcpu, r); > + ka->id_regs.normal[IDREG_IDX(r)] = pvm_calc_id_reg(vcpu, r); > > set_bit(KVM_ARCH_FLAG_ID_REGS_INITIALIZED, &kvm->arch.flags); > } > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index b9aa892616ab..195ecdac7bd6 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -2477,7 +2477,7 @@ static int set_id_reg(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > > void kvm_set_vm_id_reg(struct kvm *kvm, u32 reg, u64 val) > { > - u64 *p = __vm_id_reg(&kvm->arch, reg); > + u64 *p = __vm_id_reg(&kvm->arch.id_regs, reg); > > lockdep_assert_held(&kvm->arch.config_lock); > > -- > 2.53.0 >