July 2023 - Linux-stable-mirror

FAILED: patch "[PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072322-posing-dispatch-863e@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: b321c31c9b7b ("KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption") 0c2f9acf6ae7 ("KVM: arm64: PMU: Don't overwrite PMUSERENR with vcpu loaded") 8681f7175901 ("KVM: arm64: PMU: Restore the host's PMUSERENR_EL0") 009d6dc87a56 ("ARM: perf: Allow the use of the PMUv3 driver on 32bit ARM") 711432770f78 ("perf: pmuv3: Abstract PMU version checks") df29ddf4f04b ("arm64: perf: Abstract system register accesses away") 7755cec63ade ("arm64: perf: Move PMUv3 driver to drivers/perf") cc91b9481605 ("arm64/perf: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From b321c31c9b7b309dcde5e8854b741c8e6a9a05f0 Mon Sep 17 00:00:00 2001 From: Marc Zyngier <maz(a)kernel.org> Date: Thu, 13 Jul 2023 08:06:57 +0100 Subject: [PATCH] KVM: arm64: vgic-v4: Make the doorbell request robust w.r.t preemption Xiang reports that VMs occasionally fail to boot on GICv4.1 systems when running a preemptible kernel, as it is possible that a vCPU is blocked without requesting a doorbell interrupt. The issue is that any preemption that occurs between vgic_v4_put() and schedule() on the block path will mark the vPE as nonresident and *not* request a doorbell irq. This occurs because when the vcpu thread is resumed on its way to block, vcpu_load() will make the vPE resident again. Once the vcpu actually blocks, we don't request a doorbell anymore, and the vcpu won't be woken up on interrupt delivery. Fix it by tracking that we're entering WFI, and key the doorbell request on that flag. This allows us not to make the vPE resident when going through a preempt/schedule cycle, meaning we don't lose any state. Cc: stable(a)vger.kernel.org Fixes: 8e01d9a396e6 ("KVM: arm64: vgic-v4: Move the GICv4 residency flow to be driven by vcpu_load/put") Reported-by: Xiang Chen <chenxiang66(a)hisilicon.com> Suggested-by: Zenghui Yu <yuzenghui(a)huawei.com> Tested-by: Xiang Chen <chenxiang66(a)hisilicon.com> Co-developed-by: Oliver Upton <oliver.upton(a)linux.dev> Signed-off-by: Marc Zyngier <maz(a)kernel.org> Acked-by: Zenghui Yu <yuzenghui(a)huawei.com> Link: https://lore.kernel.org/r/20230713070657.3873244-1-maz@kernel.org Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 8b6096753740..d3dd05bbfe23 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -727,6 +727,8 @@ struct kvm_vcpu_arch { #define DBG_SS_ACTIVE_PENDING __vcpu_single_flag(sflags, BIT(5)) /* PMUSERENR for the guest EL0 is on physical CPU */ #define PMUSERENR_ON_CPU __vcpu_single_flag(sflags, BIT(6)) +/* WFI instruction trapped */ +#define IN_WFI __vcpu_single_flag(sflags, BIT(7)) /* Pointer to the vcpu's SVE FFR for sve_{save,load}_state() */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index a402ea5511f3..72dc53a75d1c 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -718,13 +718,15 @@ void kvm_vcpu_wfi(struct kvm_vcpu *vcpu) */ preempt_disable(); kvm_vgic_vmcr_sync(vcpu); - vgic_v4_put(vcpu, true); + vcpu_set_flag(vcpu, IN_WFI); + vgic_v4_put(vcpu); preempt_enable(); kvm_vcpu_halt(vcpu); vcpu_clear_flag(vcpu, IN_WFIT); preempt_disable(); + vcpu_clear_flag(vcpu, IN_WFI); vgic_v4_load(vcpu); preempt_enable(); } @@ -792,7 +794,7 @@ static int check_vcpu_requests(struct kvm_vcpu *vcpu) if (kvm_check_request(KVM_REQ_RELOAD_GICv4, vcpu)) { /* The distributor enable bits were changed */ preempt_disable(); - vgic_v4_put(vcpu, false); + vgic_v4_put(vcpu); vgic_v4_load(vcpu); preempt_enable(); } diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index c3b8e132d599..3dfc8b84e03e 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -749,7 +749,7 @@ void vgic_v3_put(struct kvm_vcpu *vcpu) { struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3; - WARN_ON(vgic_v4_put(vcpu, false)); + WARN_ON(vgic_v4_put(vcpu)); vgic_v3_vmcr_sync(vcpu); diff --git a/arch/arm64/kvm/vgic/vgic-v4.c b/arch/arm64/kvm/vgic/vgic-v4.c index c1c28fe680ba..339a55194b2c 100644 --- a/arch/arm64/kvm/vgic/vgic-v4.c +++ b/arch/arm64/kvm/vgic/vgic-v4.c @@ -336,14 +336,14 @@ void vgic_v4_teardown(struct kvm *kvm) its_vm->vpes = NULL; } -int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db) +int vgic_v4_put(struct kvm_vcpu *vcpu) { struct its_vpe *vpe = &vcpu->arch.vgic_cpu.vgic_v3.its_vpe; if (!vgic_supports_direct_msis(vcpu->kvm) || !vpe->resident) return 0; - return its_make_vpe_non_resident(vpe, need_db); + return its_make_vpe_non_resident(vpe, !!vcpu_get_flag(vcpu, IN_WFI)); } int vgic_v4_load(struct kvm_vcpu *vcpu) @@ -354,6 +354,9 @@ int vgic_v4_load(struct kvm_vcpu *vcpu) if (!vgic_supports_direct_msis(vcpu->kvm) || vpe->resident) return 0; + if (vcpu_get_flag(vcpu, IN_WFI)) + return 0; + /* * Before making the VPE resident, make sure the redistributor * corresponding to our current CPU expects us here. See the diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 402b545959af..5b27f94d4fad 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -431,7 +431,7 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq, int vgic_v4_load(struct kvm_vcpu *vcpu); void vgic_v4_commit(struct kvm_vcpu *vcpu); -int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db); +int vgic_v4_put(struct kvm_vcpu *vcpu); /* CPU HP callbacks */ void kvm_vgic_cpu_up(void);

2 years, 4 months

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FAILED: patch "[PATCH] KVM: arm64: Correctly handle page aging notifiers for" failed to apply to 4.14-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.14.y git checkout FETCH_HEAD git cherry-pick -x df6556adf27b7372cfcd97e1c0afb0d516c8279f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072359-overfull-ascent-520d@gregkh' --subject-prefix 'PATCH 4.14.y' HEAD^.. Possible dependencies: df6556adf27b ("KVM: arm64: Correctly handle page aging notifiers for unaligned memslot") ca5de2448c3b ("KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks") 6b91b8f95cad ("KVM: arm64: Use an opaque type for pteps") fa002e8e79b3 ("KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data") 2a611c7f87f2 ("KVM: arm64: Pass mm_ops through the visitor context") 83844a2317ec ("KVM: arm64: Stash observed pte value in visitor context") dfc7a7769ab7 ("KVM: arm64: Combine visitor arguments into a context structure") 094d00f8ca58 ("KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenance") e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory") 82bb02445de5 ("KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2") d6b4bd3f4897 ("KVM: arm64: Fixup hyp stage-1 refcount") 2ea2ff91e822 ("KVM: arm64: Refcount hyp stage-1 pgtable pages") cf0c7125d578 ("Merge branch kvm-arm64/mmu/el2-tracking into kvmarm-master/next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From df6556adf27b7372cfcd97e1c0afb0d516c8279f Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Tue, 27 Jun 2023 23:54:05 +0000 Subject: [PATCH] KVM: arm64: Correctly handle page aging notifiers for unaligned memslot Userspace is allowed to select any PAGE_SIZE aligned hva to back guest memory. This is even the case with hugepages, although it is a rather suboptimal configuration as PTE level mappings are used at stage-2. The arm64 page aging handlers have an assumption that the specified range is exactly one page/block of memory, which in the aforementioned case is not necessarily true. All together this leads to the WARN() in kvm_age_gfn() firing. However, the WARN is only part of the issue as the table walkers visit at most a single leaf PTE. For hugepage-backed memory in a memslot that isn't hugepage-aligned, page aging entirely misses accesses to the hugepage beyond the first page in the memslot. Add a new walker dedicated to handling page aging MMU notifiers capable of walking a range of PTEs. Convert kvm(_test)_age_gfn() over to the new walker and drop the WARN that caught the issue in the first place. The implementation of this walker was inspired by the test_clear_young() implementation by Yu Zhao [*], but repurposed to address a bug in the existing aging implementation. Cc: stable(a)vger.kernel.org # v5.15 Fixes: 056aad67f836 ("kvm: arm/arm64: Rework gpa callback handlers") Link: https://lore.kernel.org/kvmarm/20230526234435.662652-6-yuzhao@google.com/ Co-developed-by: Yu Zhao <yuzhao(a)google.com> Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: Reiji Watanabe <reijiw(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Reviewed-by: Shaoqin Huang <shahuang(a)redhat.com> Link: https://lore.kernel.org/r/20230627235405.4069823-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 8294a9a7e566..929d355eae0a 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -608,22 +608,26 @@ int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); /** - * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access + * flag in a page-table entry. * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). * @addr: Intermediate physical address to identify the page-table entry. + * @size: Size of the address range to visit. + * @mkold: True if the access flag should be cleared. * * The offset of @addr within a page is ignored. * - * If there is a valid, leaf page-table entry used to translate @addr, then - * clear the access flag in that entry. + * Tests and conditionally clears the access flag for every valid, leaf + * page-table entry used to translate the range [@addr, @addr + @size). * * Note that it is the caller's responsibility to invalidate the TLB after * calling this function to ensure that the updated permissions are visible * to the CPUs. * - * Return: The old page-table entry prior to clearing the flag, 0 on failure. + * Return: True if any of the visited PTEs had the access flag set. */ -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold); /** * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a @@ -645,18 +649,6 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot); -/** - * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the - * access flag set. - * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). - * @addr: Intermediate physical address to identify the page-table entry. - * - * The offset of @addr within a page is ignored. - * - * Return: True if the page-table entry has the access flag set, false otherwise. - */ -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); - /** * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point * of Coherency for guest stage-2 address diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index aa740a974e02..f7a93ef29250 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -1195,25 +1195,54 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) return pte; } -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +struct stage2_age_data { + bool mkold; + bool young; +}; + +static int stage2_age_walker(const struct kvm_pgtable_visit_ctx *ctx, + enum kvm_pgtable_walk_flags visit) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, - &pte, NULL, 0); + kvm_pte_t new = ctx->old & ~KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data *data = ctx->arg; + + if (!kvm_pte_valid(ctx->old) || new == ctx->old) + return 0; + + data->young = true; + + /* + * stage2_age_walker() is always called while holding the MMU lock for + * write, so this will always succeed. Nonetheless, this deliberately + * follows the race detection pattern of the other stage-2 walkers in + * case the locking mechanics of the MMU notifiers is ever changed. + */ + if (data->mkold && !stage2_try_set_pte(ctx, new)) + return -EAGAIN; + /* * "But where's the TLBI?!", you scream. * "Over in the core code", I sigh. * * See the '->clear_flush_young()' callback on the KVM mmu notifier. */ - return pte; + return 0; } -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL, 0); - return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data data = { + .mkold = mkold, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_age_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + WARN_ON(kvm_pgtable_walk(pgt, addr, size, &walker)); + return data.young; } int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..d3b4feed460c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1756,27 +1756,25 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { u64 size = (range->end - range->start) << PAGE_SHIFT; - kvm_pte_t kpte; - pte_t pte; if (!kvm->arch.mmu.pgt) return false; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - - kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); - pte = __pte(kpte); - return pte_valid(pte) && pte_young(pte); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, true); } bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { + u64 size = (range->end - range->start) << PAGE_SHIFT; + if (!kvm->arch.mmu.pgt) return false; - return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, false); } phys_addr_t kvm_mmu_get_httbr(void)

2 years, 4 months

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FAILED: patch "[PATCH] KVM: arm64: Correctly handle page aging notifiers for" failed to apply to 4.19-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x df6556adf27b7372cfcd97e1c0afb0d516c8279f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072357-trilogy-average-5fd9@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^.. Possible dependencies: df6556adf27b ("KVM: arm64: Correctly handle page aging notifiers for unaligned memslot") ca5de2448c3b ("KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks") 6b91b8f95cad ("KVM: arm64: Use an opaque type for pteps") fa002e8e79b3 ("KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data") 2a611c7f87f2 ("KVM: arm64: Pass mm_ops through the visitor context") 83844a2317ec ("KVM: arm64: Stash observed pte value in visitor context") dfc7a7769ab7 ("KVM: arm64: Combine visitor arguments into a context structure") 094d00f8ca58 ("KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenance") e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory") 82bb02445de5 ("KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2") d6b4bd3f4897 ("KVM: arm64: Fixup hyp stage-1 refcount") 2ea2ff91e822 ("KVM: arm64: Refcount hyp stage-1 pgtable pages") cf0c7125d578 ("Merge branch kvm-arm64/mmu/el2-tracking into kvmarm-master/next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From df6556adf27b7372cfcd97e1c0afb0d516c8279f Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Tue, 27 Jun 2023 23:54:05 +0000 Subject: [PATCH] KVM: arm64: Correctly handle page aging notifiers for unaligned memslot Userspace is allowed to select any PAGE_SIZE aligned hva to back guest memory. This is even the case with hugepages, although it is a rather suboptimal configuration as PTE level mappings are used at stage-2. The arm64 page aging handlers have an assumption that the specified range is exactly one page/block of memory, which in the aforementioned case is not necessarily true. All together this leads to the WARN() in kvm_age_gfn() firing. However, the WARN is only part of the issue as the table walkers visit at most a single leaf PTE. For hugepage-backed memory in a memslot that isn't hugepage-aligned, page aging entirely misses accesses to the hugepage beyond the first page in the memslot. Add a new walker dedicated to handling page aging MMU notifiers capable of walking a range of PTEs. Convert kvm(_test)_age_gfn() over to the new walker and drop the WARN that caught the issue in the first place. The implementation of this walker was inspired by the test_clear_young() implementation by Yu Zhao [*], but repurposed to address a bug in the existing aging implementation. Cc: stable(a)vger.kernel.org # v5.15 Fixes: 056aad67f836 ("kvm: arm/arm64: Rework gpa callback handlers") Link: https://lore.kernel.org/kvmarm/20230526234435.662652-6-yuzhao@google.com/ Co-developed-by: Yu Zhao <yuzhao(a)google.com> Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: Reiji Watanabe <reijiw(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Reviewed-by: Shaoqin Huang <shahuang(a)redhat.com> Link: https://lore.kernel.org/r/20230627235405.4069823-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 8294a9a7e566..929d355eae0a 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -608,22 +608,26 @@ int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); /** - * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access + * flag in a page-table entry. * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). * @addr: Intermediate physical address to identify the page-table entry. + * @size: Size of the address range to visit. + * @mkold: True if the access flag should be cleared. * * The offset of @addr within a page is ignored. * - * If there is a valid, leaf page-table entry used to translate @addr, then - * clear the access flag in that entry. + * Tests and conditionally clears the access flag for every valid, leaf + * page-table entry used to translate the range [@addr, @addr + @size). * * Note that it is the caller's responsibility to invalidate the TLB after * calling this function to ensure that the updated permissions are visible * to the CPUs. * - * Return: The old page-table entry prior to clearing the flag, 0 on failure. + * Return: True if any of the visited PTEs had the access flag set. */ -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold); /** * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a @@ -645,18 +649,6 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot); -/** - * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the - * access flag set. - * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). - * @addr: Intermediate physical address to identify the page-table entry. - * - * The offset of @addr within a page is ignored. - * - * Return: True if the page-table entry has the access flag set, false otherwise. - */ -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); - /** * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point * of Coherency for guest stage-2 address diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index aa740a974e02..f7a93ef29250 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -1195,25 +1195,54 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) return pte; } -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +struct stage2_age_data { + bool mkold; + bool young; +}; + +static int stage2_age_walker(const struct kvm_pgtable_visit_ctx *ctx, + enum kvm_pgtable_walk_flags visit) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, - &pte, NULL, 0); + kvm_pte_t new = ctx->old & ~KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data *data = ctx->arg; + + if (!kvm_pte_valid(ctx->old) || new == ctx->old) + return 0; + + data->young = true; + + /* + * stage2_age_walker() is always called while holding the MMU lock for + * write, so this will always succeed. Nonetheless, this deliberately + * follows the race detection pattern of the other stage-2 walkers in + * case the locking mechanics of the MMU notifiers is ever changed. + */ + if (data->mkold && !stage2_try_set_pte(ctx, new)) + return -EAGAIN; + /* * "But where's the TLBI?!", you scream. * "Over in the core code", I sigh. * * See the '->clear_flush_young()' callback on the KVM mmu notifier. */ - return pte; + return 0; } -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL, 0); - return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data data = { + .mkold = mkold, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_age_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + WARN_ON(kvm_pgtable_walk(pgt, addr, size, &walker)); + return data.young; } int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..d3b4feed460c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1756,27 +1756,25 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { u64 size = (range->end - range->start) << PAGE_SHIFT; - kvm_pte_t kpte; - pte_t pte; if (!kvm->arch.mmu.pgt) return false; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - - kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); - pte = __pte(kpte); - return pte_valid(pte) && pte_young(pte); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, true); } bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { + u64 size = (range->end - range->start) << PAGE_SHIFT; + if (!kvm->arch.mmu.pgt) return false; - return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, false); } phys_addr_t kvm_mmu_get_httbr(void)

2 years, 4 months

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FAILED: patch "[PATCH] KVM: arm64: Correctly handle page aging notifiers for" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x df6556adf27b7372cfcd97e1c0afb0d516c8279f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072356-margin-freckled-cde8@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: df6556adf27b ("KVM: arm64: Correctly handle page aging notifiers for unaligned memslot") ca5de2448c3b ("KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks") 6b91b8f95cad ("KVM: arm64: Use an opaque type for pteps") fa002e8e79b3 ("KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data") 2a611c7f87f2 ("KVM: arm64: Pass mm_ops through the visitor context") 83844a2317ec ("KVM: arm64: Stash observed pte value in visitor context") dfc7a7769ab7 ("KVM: arm64: Combine visitor arguments into a context structure") 094d00f8ca58 ("KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenance") e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory") 82bb02445de5 ("KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2") d6b4bd3f4897 ("KVM: arm64: Fixup hyp stage-1 refcount") 2ea2ff91e822 ("KVM: arm64: Refcount hyp stage-1 pgtable pages") cf0c7125d578 ("Merge branch kvm-arm64/mmu/el2-tracking into kvmarm-master/next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From df6556adf27b7372cfcd97e1c0afb0d516c8279f Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Tue, 27 Jun 2023 23:54:05 +0000 Subject: [PATCH] KVM: arm64: Correctly handle page aging notifiers for unaligned memslot Userspace is allowed to select any PAGE_SIZE aligned hva to back guest memory. This is even the case with hugepages, although it is a rather suboptimal configuration as PTE level mappings are used at stage-2. The arm64 page aging handlers have an assumption that the specified range is exactly one page/block of memory, which in the aforementioned case is not necessarily true. All together this leads to the WARN() in kvm_age_gfn() firing. However, the WARN is only part of the issue as the table walkers visit at most a single leaf PTE. For hugepage-backed memory in a memslot that isn't hugepage-aligned, page aging entirely misses accesses to the hugepage beyond the first page in the memslot. Add a new walker dedicated to handling page aging MMU notifiers capable of walking a range of PTEs. Convert kvm(_test)_age_gfn() over to the new walker and drop the WARN that caught the issue in the first place. The implementation of this walker was inspired by the test_clear_young() implementation by Yu Zhao [*], but repurposed to address a bug in the existing aging implementation. Cc: stable(a)vger.kernel.org # v5.15 Fixes: 056aad67f836 ("kvm: arm/arm64: Rework gpa callback handlers") Link: https://lore.kernel.org/kvmarm/20230526234435.662652-6-yuzhao@google.com/ Co-developed-by: Yu Zhao <yuzhao(a)google.com> Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: Reiji Watanabe <reijiw(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Reviewed-by: Shaoqin Huang <shahuang(a)redhat.com> Link: https://lore.kernel.org/r/20230627235405.4069823-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 8294a9a7e566..929d355eae0a 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -608,22 +608,26 @@ int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); /** - * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access + * flag in a page-table entry. * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). * @addr: Intermediate physical address to identify the page-table entry. + * @size: Size of the address range to visit. + * @mkold: True if the access flag should be cleared. * * The offset of @addr within a page is ignored. * - * If there is a valid, leaf page-table entry used to translate @addr, then - * clear the access flag in that entry. + * Tests and conditionally clears the access flag for every valid, leaf + * page-table entry used to translate the range [@addr, @addr + @size). * * Note that it is the caller's responsibility to invalidate the TLB after * calling this function to ensure that the updated permissions are visible * to the CPUs. * - * Return: The old page-table entry prior to clearing the flag, 0 on failure. + * Return: True if any of the visited PTEs had the access flag set. */ -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold); /** * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a @@ -645,18 +649,6 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot); -/** - * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the - * access flag set. - * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). - * @addr: Intermediate physical address to identify the page-table entry. - * - * The offset of @addr within a page is ignored. - * - * Return: True if the page-table entry has the access flag set, false otherwise. - */ -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); - /** * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point * of Coherency for guest stage-2 address diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index aa740a974e02..f7a93ef29250 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -1195,25 +1195,54 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) return pte; } -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +struct stage2_age_data { + bool mkold; + bool young; +}; + +static int stage2_age_walker(const struct kvm_pgtable_visit_ctx *ctx, + enum kvm_pgtable_walk_flags visit) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, - &pte, NULL, 0); + kvm_pte_t new = ctx->old & ~KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data *data = ctx->arg; + + if (!kvm_pte_valid(ctx->old) || new == ctx->old) + return 0; + + data->young = true; + + /* + * stage2_age_walker() is always called while holding the MMU lock for + * write, so this will always succeed. Nonetheless, this deliberately + * follows the race detection pattern of the other stage-2 walkers in + * case the locking mechanics of the MMU notifiers is ever changed. + */ + if (data->mkold && !stage2_try_set_pte(ctx, new)) + return -EAGAIN; + /* * "But where's the TLBI?!", you scream. * "Over in the core code", I sigh. * * See the '->clear_flush_young()' callback on the KVM mmu notifier. */ - return pte; + return 0; } -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL, 0); - return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data data = { + .mkold = mkold, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_age_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + WARN_ON(kvm_pgtable_walk(pgt, addr, size, &walker)); + return data.young; } int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..d3b4feed460c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1756,27 +1756,25 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { u64 size = (range->end - range->start) << PAGE_SHIFT; - kvm_pte_t kpte; - pte_t pte; if (!kvm->arch.mmu.pgt) return false; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - - kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); - pte = __pte(kpte); - return pte_valid(pte) && pte_young(pte); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, true); } bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { + u64 size = (range->end - range->start) << PAGE_SHIFT; + if (!kvm->arch.mmu.pgt) return false; - return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, false); } phys_addr_t kvm_mmu_get_httbr(void)

2 years, 4 months

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FAILED: patch "[PATCH] KVM: arm64: Correctly handle page aging notifiers for" failed to apply to 5.10-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x df6556adf27b7372cfcd97e1c0afb0d516c8279f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072354-sublet-observing-2ff8@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: df6556adf27b ("KVM: arm64: Correctly handle page aging notifiers for unaligned memslot") ca5de2448c3b ("KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks") 6b91b8f95cad ("KVM: arm64: Use an opaque type for pteps") fa002e8e79b3 ("KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data") 2a611c7f87f2 ("KVM: arm64: Pass mm_ops through the visitor context") 83844a2317ec ("KVM: arm64: Stash observed pte value in visitor context") dfc7a7769ab7 ("KVM: arm64: Combine visitor arguments into a context structure") 094d00f8ca58 ("KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenance") e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory") 82bb02445de5 ("KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2") d6b4bd3f4897 ("KVM: arm64: Fixup hyp stage-1 refcount") 2ea2ff91e822 ("KVM: arm64: Refcount hyp stage-1 pgtable pages") cf0c7125d578 ("Merge branch kvm-arm64/mmu/el2-tracking into kvmarm-master/next") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From df6556adf27b7372cfcd97e1c0afb0d516c8279f Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Tue, 27 Jun 2023 23:54:05 +0000 Subject: [PATCH] KVM: arm64: Correctly handle page aging notifiers for unaligned memslot Userspace is allowed to select any PAGE_SIZE aligned hva to back guest memory. This is even the case with hugepages, although it is a rather suboptimal configuration as PTE level mappings are used at stage-2. The arm64 page aging handlers have an assumption that the specified range is exactly one page/block of memory, which in the aforementioned case is not necessarily true. All together this leads to the WARN() in kvm_age_gfn() firing. However, the WARN is only part of the issue as the table walkers visit at most a single leaf PTE. For hugepage-backed memory in a memslot that isn't hugepage-aligned, page aging entirely misses accesses to the hugepage beyond the first page in the memslot. Add a new walker dedicated to handling page aging MMU notifiers capable of walking a range of PTEs. Convert kvm(_test)_age_gfn() over to the new walker and drop the WARN that caught the issue in the first place. The implementation of this walker was inspired by the test_clear_young() implementation by Yu Zhao [*], but repurposed to address a bug in the existing aging implementation. Cc: stable(a)vger.kernel.org # v5.15 Fixes: 056aad67f836 ("kvm: arm/arm64: Rework gpa callback handlers") Link: https://lore.kernel.org/kvmarm/20230526234435.662652-6-yuzhao@google.com/ Co-developed-by: Yu Zhao <yuzhao(a)google.com> Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: Reiji Watanabe <reijiw(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Reviewed-by: Shaoqin Huang <shahuang(a)redhat.com> Link: https://lore.kernel.org/r/20230627235405.4069823-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 8294a9a7e566..929d355eae0a 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -608,22 +608,26 @@ int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); /** - * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access + * flag in a page-table entry. * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). * @addr: Intermediate physical address to identify the page-table entry. + * @size: Size of the address range to visit. + * @mkold: True if the access flag should be cleared. * * The offset of @addr within a page is ignored. * - * If there is a valid, leaf page-table entry used to translate @addr, then - * clear the access flag in that entry. + * Tests and conditionally clears the access flag for every valid, leaf + * page-table entry used to translate the range [@addr, @addr + @size). * * Note that it is the caller's responsibility to invalidate the TLB after * calling this function to ensure that the updated permissions are visible * to the CPUs. * - * Return: The old page-table entry prior to clearing the flag, 0 on failure. + * Return: True if any of the visited PTEs had the access flag set. */ -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold); /** * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a @@ -645,18 +649,6 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot); -/** - * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the - * access flag set. - * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). - * @addr: Intermediate physical address to identify the page-table entry. - * - * The offset of @addr within a page is ignored. - * - * Return: True if the page-table entry has the access flag set, false otherwise. - */ -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); - /** * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point * of Coherency for guest stage-2 address diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index aa740a974e02..f7a93ef29250 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -1195,25 +1195,54 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) return pte; } -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +struct stage2_age_data { + bool mkold; + bool young; +}; + +static int stage2_age_walker(const struct kvm_pgtable_visit_ctx *ctx, + enum kvm_pgtable_walk_flags visit) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, - &pte, NULL, 0); + kvm_pte_t new = ctx->old & ~KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data *data = ctx->arg; + + if (!kvm_pte_valid(ctx->old) || new == ctx->old) + return 0; + + data->young = true; + + /* + * stage2_age_walker() is always called while holding the MMU lock for + * write, so this will always succeed. Nonetheless, this deliberately + * follows the race detection pattern of the other stage-2 walkers in + * case the locking mechanics of the MMU notifiers is ever changed. + */ + if (data->mkold && !stage2_try_set_pte(ctx, new)) + return -EAGAIN; + /* * "But where's the TLBI?!", you scream. * "Over in the core code", I sigh. * * See the '->clear_flush_young()' callback on the KVM mmu notifier. */ - return pte; + return 0; } -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL, 0); - return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data data = { + .mkold = mkold, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_age_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + WARN_ON(kvm_pgtable_walk(pgt, addr, size, &walker)); + return data.young; } int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..d3b4feed460c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1756,27 +1756,25 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { u64 size = (range->end - range->start) << PAGE_SHIFT; - kvm_pte_t kpte; - pte_t pte; if (!kvm->arch.mmu.pgt) return false; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - - kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); - pte = __pte(kpte); - return pte_valid(pte) && pte_young(pte); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, true); } bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { + u64 size = (range->end - range->start) << PAGE_SHIFT; + if (!kvm->arch.mmu.pgt) return false; - return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, false); } phys_addr_t kvm_mmu_get_httbr(void)

2 years, 4 months

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FAILED: patch "[PATCH] KVM: arm64: Correctly handle page aging notifiers for" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x df6556adf27b7372cfcd97e1c0afb0d516c8279f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072352-ooze-childcare-fd84@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: df6556adf27b ("KVM: arm64: Correctly handle page aging notifiers for unaligned memslot") ca5de2448c3b ("KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks") 6b91b8f95cad ("KVM: arm64: Use an opaque type for pteps") fa002e8e79b3 ("KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data") 2a611c7f87f2 ("KVM: arm64: Pass mm_ops through the visitor context") 83844a2317ec ("KVM: arm64: Stash observed pte value in visitor context") dfc7a7769ab7 ("KVM: arm64: Combine visitor arguments into a context structure") 094d00f8ca58 ("KVM: arm64: pkvm: Use the mm_ops indirection for cache maintenance") e82edcc75c4e ("KVM: arm64: Implement do_share() helper for sharing memory") 82bb02445de5 ("KVM: arm64: Implement kvm_pgtable_hyp_unmap() at EL2") d6b4bd3f4897 ("KVM: arm64: Fixup hyp stage-1 refcount") 2ea2ff91e822 ("KVM: arm64: Refcount hyp stage-1 pgtable pages") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From df6556adf27b7372cfcd97e1c0afb0d516c8279f Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Tue, 27 Jun 2023 23:54:05 +0000 Subject: [PATCH] KVM: arm64: Correctly handle page aging notifiers for unaligned memslot Userspace is allowed to select any PAGE_SIZE aligned hva to back guest memory. This is even the case with hugepages, although it is a rather suboptimal configuration as PTE level mappings are used at stage-2. The arm64 page aging handlers have an assumption that the specified range is exactly one page/block of memory, which in the aforementioned case is not necessarily true. All together this leads to the WARN() in kvm_age_gfn() firing. However, the WARN is only part of the issue as the table walkers visit at most a single leaf PTE. For hugepage-backed memory in a memslot that isn't hugepage-aligned, page aging entirely misses accesses to the hugepage beyond the first page in the memslot. Add a new walker dedicated to handling page aging MMU notifiers capable of walking a range of PTEs. Convert kvm(_test)_age_gfn() over to the new walker and drop the WARN that caught the issue in the first place. The implementation of this walker was inspired by the test_clear_young() implementation by Yu Zhao [*], but repurposed to address a bug in the existing aging implementation. Cc: stable(a)vger.kernel.org # v5.15 Fixes: 056aad67f836 ("kvm: arm/arm64: Rework gpa callback handlers") Link: https://lore.kernel.org/kvmarm/20230526234435.662652-6-yuzhao@google.com/ Co-developed-by: Yu Zhao <yuzhao(a)google.com> Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: Reiji Watanabe <reijiw(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Reviewed-by: Shaoqin Huang <shahuang(a)redhat.com> Link: https://lore.kernel.org/r/20230627235405.4069823-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 8294a9a7e566..929d355eae0a 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -608,22 +608,26 @@ int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); /** - * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access + * flag in a page-table entry. * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). * @addr: Intermediate physical address to identify the page-table entry. + * @size: Size of the address range to visit. + * @mkold: True if the access flag should be cleared. * * The offset of @addr within a page is ignored. * - * If there is a valid, leaf page-table entry used to translate @addr, then - * clear the access flag in that entry. + * Tests and conditionally clears the access flag for every valid, leaf + * page-table entry used to translate the range [@addr, @addr + @size). * * Note that it is the caller's responsibility to invalidate the TLB after * calling this function to ensure that the updated permissions are visible * to the CPUs. * - * Return: The old page-table entry prior to clearing the flag, 0 on failure. + * Return: True if any of the visited PTEs had the access flag set. */ -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold); /** * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a @@ -645,18 +649,6 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot); -/** - * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the - * access flag set. - * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). - * @addr: Intermediate physical address to identify the page-table entry. - * - * The offset of @addr within a page is ignored. - * - * Return: True if the page-table entry has the access flag set, false otherwise. - */ -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); - /** * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point * of Coherency for guest stage-2 address diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index aa740a974e02..f7a93ef29250 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -1195,25 +1195,54 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) return pte; } -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +struct stage2_age_data { + bool mkold; + bool young; +}; + +static int stage2_age_walker(const struct kvm_pgtable_visit_ctx *ctx, + enum kvm_pgtable_walk_flags visit) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, - &pte, NULL, 0); + kvm_pte_t new = ctx->old & ~KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data *data = ctx->arg; + + if (!kvm_pte_valid(ctx->old) || new == ctx->old) + return 0; + + data->young = true; + + /* + * stage2_age_walker() is always called while holding the MMU lock for + * write, so this will always succeed. Nonetheless, this deliberately + * follows the race detection pattern of the other stage-2 walkers in + * case the locking mechanics of the MMU notifiers is ever changed. + */ + if (data->mkold && !stage2_try_set_pte(ctx, new)) + return -EAGAIN; + /* * "But where's the TLBI?!", you scream. * "Over in the core code", I sigh. * * See the '->clear_flush_young()' callback on the KVM mmu notifier. */ - return pte; + return 0; } -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL, 0); - return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data data = { + .mkold = mkold, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_age_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + WARN_ON(kvm_pgtable_walk(pgt, addr, size, &walker)); + return data.young; } int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..d3b4feed460c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1756,27 +1756,25 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { u64 size = (range->end - range->start) << PAGE_SHIFT; - kvm_pte_t kpte; - pte_t pte; if (!kvm->arch.mmu.pgt) return false; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - - kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); - pte = __pte(kpte); - return pte_valid(pte) && pte_young(pte); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, true); } bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { + u64 size = (range->end - range->start) << PAGE_SHIFT; + if (!kvm->arch.mmu.pgt) return false; - return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, false); } phys_addr_t kvm_mmu_get_httbr(void)

2 years, 4 months

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FAILED: patch "[PATCH] KVM: arm64: Correctly handle page aging notifiers for" failed to apply to 6.1-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x df6556adf27b7372cfcd97e1c0afb0d516c8279f # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072351-slackness-unlearned-6f45@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: df6556adf27b ("KVM: arm64: Correctly handle page aging notifiers for unaligned memslot") ca5de2448c3b ("KVM: arm64: Atomically update stage 2 leaf attributes in parallel walks") 6b91b8f95cad ("KVM: arm64: Use an opaque type for pteps") fa002e8e79b3 ("KVM: arm64: Don't pass kvm_pgtable through kvm_pgtable_walk_data") 2a611c7f87f2 ("KVM: arm64: Pass mm_ops through the visitor context") 83844a2317ec ("KVM: arm64: Stash observed pte value in visitor context") dfc7a7769ab7 ("KVM: arm64: Combine visitor arguments into a context structure") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From df6556adf27b7372cfcd97e1c0afb0d516c8279f Mon Sep 17 00:00:00 2001 From: Oliver Upton <oliver.upton(a)linux.dev> Date: Tue, 27 Jun 2023 23:54:05 +0000 Subject: [PATCH] KVM: arm64: Correctly handle page aging notifiers for unaligned memslot Userspace is allowed to select any PAGE_SIZE aligned hva to back guest memory. This is even the case with hugepages, although it is a rather suboptimal configuration as PTE level mappings are used at stage-2. The arm64 page aging handlers have an assumption that the specified range is exactly one page/block of memory, which in the aforementioned case is not necessarily true. All together this leads to the WARN() in kvm_age_gfn() firing. However, the WARN is only part of the issue as the table walkers visit at most a single leaf PTE. For hugepage-backed memory in a memslot that isn't hugepage-aligned, page aging entirely misses accesses to the hugepage beyond the first page in the memslot. Add a new walker dedicated to handling page aging MMU notifiers capable of walking a range of PTEs. Convert kvm(_test)_age_gfn() over to the new walker and drop the WARN that caught the issue in the first place. The implementation of this walker was inspired by the test_clear_young() implementation by Yu Zhao [*], but repurposed to address a bug in the existing aging implementation. Cc: stable(a)vger.kernel.org # v5.15 Fixes: 056aad67f836 ("kvm: arm/arm64: Rework gpa callback handlers") Link: https://lore.kernel.org/kvmarm/20230526234435.662652-6-yuzhao@google.com/ Co-developed-by: Yu Zhao <yuzhao(a)google.com> Signed-off-by: Yu Zhao <yuzhao(a)google.com> Reported-by: Reiji Watanabe <reijiw(a)google.com> Reviewed-by: Marc Zyngier <maz(a)kernel.org> Reviewed-by: Shaoqin Huang <shahuang(a)redhat.com> Link: https://lore.kernel.org/r/20230627235405.4069823-1-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton(a)linux.dev> diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index 8294a9a7e566..929d355eae0a 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -608,22 +608,26 @@ int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); /** - * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * kvm_pgtable_stage2_test_clear_young() - Test and optionally clear the access + * flag in a page-table entry. * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). * @addr: Intermediate physical address to identify the page-table entry. + * @size: Size of the address range to visit. + * @mkold: True if the access flag should be cleared. * * The offset of @addr within a page is ignored. * - * If there is a valid, leaf page-table entry used to translate @addr, then - * clear the access flag in that entry. + * Tests and conditionally clears the access flag for every valid, leaf + * page-table entry used to translate the range [@addr, @addr + @size). * * Note that it is the caller's responsibility to invalidate the TLB after * calling this function to ensure that the updated permissions are visible * to the CPUs. * - * Return: The old page-table entry prior to clearing the flag, 0 on failure. + * Return: True if any of the visited PTEs had the access flag set. */ -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold); /** * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a @@ -645,18 +649,6 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot); -/** - * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the - * access flag set. - * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init*(). - * @addr: Intermediate physical address to identify the page-table entry. - * - * The offset of @addr within a page is ignored. - * - * Return: True if the page-table entry has the access flag set, false otherwise. - */ -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); - /** * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point * of Coherency for guest stage-2 address diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c index aa740a974e02..f7a93ef29250 100644 --- a/arch/arm64/kvm/hyp/pgtable.c +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -1195,25 +1195,54 @@ kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) return pte; } -kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +struct stage2_age_data { + bool mkold; + bool young; +}; + +static int stage2_age_walker(const struct kvm_pgtable_visit_ctx *ctx, + enum kvm_pgtable_walk_flags visit) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, - &pte, NULL, 0); + kvm_pte_t new = ctx->old & ~KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data *data = ctx->arg; + + if (!kvm_pte_valid(ctx->old) || new == ctx->old) + return 0; + + data->young = true; + + /* + * stage2_age_walker() is always called while holding the MMU lock for + * write, so this will always succeed. Nonetheless, this deliberately + * follows the race detection pattern of the other stage-2 walkers in + * case the locking mechanics of the MMU notifiers is ever changed. + */ + if (data->mkold && !stage2_try_set_pte(ctx, new)) + return -EAGAIN; + /* * "But where's the TLBI?!", you scream. * "Over in the core code", I sigh. * * See the '->clear_flush_young()' callback on the KVM mmu notifier. */ - return pte; + return 0; } -bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +bool kvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, + u64 size, bool mkold) { - kvm_pte_t pte = 0; - stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL, 0); - return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; + struct stage2_age_data data = { + .mkold = mkold, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_age_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + WARN_ON(kvm_pgtable_walk(pgt, addr, size, &walker)); + return data.young; } int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 6db9ef288ec3..d3b4feed460c 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1756,27 +1756,25 @@ bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { u64 size = (range->end - range->start) << PAGE_SHIFT; - kvm_pte_t kpte; - pte_t pte; if (!kvm->arch.mmu.pgt) return false; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - - kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); - pte = __pte(kpte); - return pte_valid(pte) && pte_young(pte); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, true); } bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) { + u64 size = (range->end - range->start) << PAGE_SHIFT; + if (!kvm->arch.mmu.pgt) return false; - return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, - range->start << PAGE_SHIFT); + return kvm_pgtable_stage2_test_clear_young(kvm->arch.mmu.pgt, + range->start << PAGE_SHIFT, + size, false); } phys_addr_t kvm_mmu_get_httbr(void)

2 years, 4 months

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[PATCH 6.1.y 0/6] BPF selftests fixes for 6.1 branch

by Eduard Zingerman

Recently Luiz Capitulino reported BPF test failure for kernel version 6.1.36 (see [7]). The following test_verifier test failed: "precise: ST insn causing spi > allocated_stack". After back-port of the following upstream commit: ecdf985d7615 ("bpf: track immediate values written to stack by BPF_ST instruction") Investigation in [8] shows that test failure is not a bug, but a difference in BPF verifier behavior between upstream, where commits [1,2,3] by Andrii Nakryiko are present, and 6.1.36, where these commits are absent. Both Luiz and Greg suggested back-porting [1,2,3] from upstream to avoid divergences. Commits [1,2,3] break test_progs selftest "align/packet variable offset", commit [4] fixes this selftest. I did some additional testing using the following compiler versions: - Kernel compilation - gcc version 11.3.0 - BPF tests compilation - clang version 16.0.6 - clang version 17.0.0 (fa46feb31481) And identified a few more failing BPF selftests: - Tests failing with LLVM 16: - test_verifier: - precise: ST insn causing spi > allocated_stack FAIL (fixed by [1,2,3]) - test_progs: - sk_assign (fixed by [6]) - Tests failing with LLVM 17: - test_verifier: - precise: ST insn causing spi > allocated_stack FAIL (fixed by [1,2,3]) - test_progs: - fexit_bpf2bpf/func_replace_verify (fixed by [5]) - fexit_bpf2bpf/func_replace_return_code (fixed by [5]) - sk_assign (fixed by [6]) Commits [4,5,6] only apply to BPF selftests and don't change verifier behavior. After applying all of the listed commits I have test_verifier, test_progs, test_progs-no_alu32 and test_maps passing on my x86 setup, both for LLVM 16 and LLVM 17. Upstream commits in chronological order: [1] be2ef8161572 ("bpf: allow precision tracking for programs with subprogs") [2] f63181b6ae79 ("bpf: stop setting precise in current state") [3] 7a830b53c17b ("bpf: aggressively forget precise markings during state checkpointing") [4] 4f999b767769 ("selftests/bpf: make test_align selftest more robust") [5] 63d78b7e8ca2 ("selftests/bpf: Workaround verification failure for fexit_bpf2bpf/func_replace_return_code") [6] 7ce878ca81bc ("selftests/bpf: Fix sk_assign on s390x") Links: [7] https://lore.kernel.org/stable/935c4751-d368-df29-33a6-9f4fcae720fa@amazon.… [8] https://lore.kernel.org/stable/c9b10a8a551edafdfec855fbd35757c6238ad258.cam… Reported-by: Luiz Capitulino <luizcap(a)amazon.com> Andrii Nakryiko (4): bpf: allow precision tracking for programs with subprogs bpf: stop setting precise in current state bpf: aggressively forget precise markings during state checkpointing selftests/bpf: make test_align selftest more robust Ilya Leoshkevich (1): selftests/bpf: Fix sk_assign on s390x Yonghong Song (1): selftests/bpf: Workaround verification failure for fexit_bpf2bpf/func_replace_return_code kernel/bpf/verifier.c | 202 ++++++++++++++++-- .../testing/selftests/bpf/prog_tests/align.c | 38 ++-- .../selftests/bpf/prog_tests/sk_assign.c | 25 ++- .../selftests/bpf/progs/connect4_prog.c | 2 +- .../selftests/bpf/progs/test_sk_assign.c | 11 + .../bpf/progs/test_sk_assign_libbpf.c | 3 + 6 files changed, 247 insertions(+), 34 deletions(-) create mode 100644 tools/testing/selftests/bpf/progs/test_sk_assign_libbpf.c -- 2.41.0

2 years, 4 months

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Build error in v5.4.y-queue

by Guenter Roeck

Seen in arm:allmodconfig and arm64:allmodconfig builds with v5.4.249-278-g78f9a3d1c959. sound/soc/mediatek/mt8173/mt8173-afe-pcm.c: In function 'mt8173_afe_pcm_dev_probe': sound/soc/mediatek/mt8173/mt8173-afe-pcm.c:1159:17: error: label 'err_cleanup_components' used but not defined Guenter

2 years, 4 months

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FAILED: patch "[PATCH] ASoC: mediatek: mt8173: Fix irq error path" failed to apply to 5.4-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.4.y git checkout FETCH_HEAD git cherry-pick -x f9c058d14f4fe23ef523a7ff73734d51c151683c # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2023072316-squatting-handiness-1c06@gregkh' --subject-prefix 'PATCH 5.4.y' HEAD^.. Possible dependencies: f9c058d14f4f ("ASoC: mediatek: mt8173: Fix irq error path") 4cbb264d4e91 ("ASoC: mediatek: mt8173: Enable IRQ when pdata is ready") 8c32984bc7da ("ASoC: mediatek: mt8173: Fix debugfs registration for components") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From f9c058d14f4fe23ef523a7ff73734d51c151683c Mon Sep 17 00:00:00 2001 From: Ricardo Ribalda Delgado <ribalda(a)chromium.org> Date: Mon, 12 Jun 2023 11:05:32 +0200 Subject: [PATCH] ASoC: mediatek: mt8173: Fix irq error path After reordering the irq probe, the error path was not properly done. Lets fix it. Reported-by: Dan Carpenter <dan.carpenter(a)linaro.org> Cc: stable(a)kernel.org Fixes: 4cbb264d4e91 ("ASoC: mediatek: mt8173: Enable IRQ when pdata is ready") Signed-off-by: Ricardo Ribalda Delgado <ribalda(a)chromium.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno(a)collabora.com> Link: https://lore.kernel.org/r/20230612-mt8173-fixup-v2-2-432aa99ce24d@chromium.… Signed-off-by: Mark Brown <broonie(a)kernel.org> diff --git a/sound/soc/mediatek/mt8173/mt8173-afe-pcm.c b/sound/soc/mediatek/mt8173/mt8173-afe-pcm.c index ff25c44070a3..06269f7e3756 100644 --- a/sound/soc/mediatek/mt8173/mt8173-afe-pcm.c +++ b/sound/soc/mediatek/mt8173/mt8173-afe-pcm.c @@ -1070,6 +1070,10 @@ static int mt8173_afe_pcm_dev_probe(struct platform_device *pdev) afe->dev = &pdev->dev; + irq_id = platform_get_irq(pdev, 0); + if (irq_id <= 0) + return irq_id < 0 ? irq_id : -ENXIO; + afe->base_addr = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(afe->base_addr)) return PTR_ERR(afe->base_addr); @@ -1175,14 +1179,11 @@ static int mt8173_afe_pcm_dev_probe(struct platform_device *pdev) if (ret) goto err_cleanup_components; - irq_id = platform_get_irq(pdev, 0); - if (irq_id <= 0) - return irq_id < 0 ? irq_id : -ENXIO; ret = devm_request_irq(afe->dev, irq_id, mt8173_afe_irq_handler, 0, "Afe_ISR_Handle", (void *)afe); if (ret) { dev_err(afe->dev, "could not request_irq\n"); - goto err_pm_disable; + goto err_cleanup_components; } dev_info(&pdev->dev, "MT8173 AFE driver initialized.\n");

2 years, 4 months

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