From: James Hogan <james.hogan@imgtec.com> To: <linux-mips@linux-mips.org> Cc: "James Hogan" <james.hogan@imgtec.com>, "Paolo Bonzini" <pbonzini@redhat.com>, "Radim Krčmář" <rkrcmar@redhat.com>, "Ralf Baechle" <ralf@linux-mips.org>, kvm@vger.kernel.org Subject: [PATCH v2 18/30] KVM: MIPS/TLB: Fix off-by-one in TLB invalidate Date: Thu, 2 Feb 2017 12:04:31 +0000 [thread overview] Message-ID: <45c9a17158efd486f17ced44d54000b5420fe4eb.1486036366.git-series.james.hogan@imgtec.com> (raw) In-Reply-To: <cover.e37f86dece46fc3ed00a075d68119cab361cda8e.1486036366.git-series.james.hogan@imgtec.com> kvm_mips_host_tlb_inv() uses the TLBP instruction to probe the host TLB for an entry matching the given guest virtual address, and determines whether a match was found based on whether CP0_Index > 0. This is technically incorrect as an index of 0 (with the high bit clear) is a perfectly valid TLB index. This is harmless at the moment due to the use of at least 1 wired TLB entry for the KVM commpage, however we will soon be ridding ourselves of that particular wired entry so lets fix the condition in case the entry needing invalidation does land at TLB index 0. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org --- arch/mips/kvm/tlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c index 6c1f894b8754..4bf82613d440 100644 --- a/arch/mips/kvm/tlb.c +++ b/arch/mips/kvm/tlb.c @@ -282,7 +282,7 @@ int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va) if (idx >= current_cpu_data.tlbsize) BUG(); - if (idx > 0) { + if (idx >= 0) { write_c0_entryhi(UNIQUE_ENTRYHI(idx)); write_c0_entrylo0(0); write_c0_entrylo1(0); @@ -297,7 +297,7 @@ int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va) local_irq_restore(flags); - if (idx > 0) + if (idx >= 0) kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__, (va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu), idx); -- git-series 0.8.10
WARNING: multiple messages have this Message-ID (diff)
From: James Hogan <james.hogan@imgtec.com> To: linux-mips@linux-mips.org Cc: "James Hogan" <james.hogan@imgtec.com>, "Paolo Bonzini" <pbonzini@redhat.com>, "Radim Krčmář" <rkrcmar@redhat.com>, "Ralf Baechle" <ralf@linux-mips.org>, kvm@vger.kernel.org Subject: [PATCH v2 18/30] KVM: MIPS/TLB: Fix off-by-one in TLB invalidate Date: Thu, 2 Feb 2017 12:04:31 +0000 [thread overview] Message-ID: <45c9a17158efd486f17ced44d54000b5420fe4eb.1486036366.git-series.james.hogan@imgtec.com> (raw) Message-ID: <20170202120431.oTjRmGaiHCfpqqJoiUN_RhhBNIHz_2VKOq5-UMru9Bw@z> (raw) In-Reply-To: <cover.e37f86dece46fc3ed00a075d68119cab361cda8e.1486036366.git-series.james.hogan@imgtec.com> kvm_mips_host_tlb_inv() uses the TLBP instruction to probe the host TLB for an entry matching the given guest virtual address, and determines whether a match was found based on whether CP0_Index > 0. This is technically incorrect as an index of 0 (with the high bit clear) is a perfectly valid TLB index. This is harmless at the moment due to the use of at least 1 wired TLB entry for the KVM commpage, however we will soon be ridding ourselves of that particular wired entry so lets fix the condition in case the entry needing invalidation does land at TLB index 0. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org --- arch/mips/kvm/tlb.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c index 6c1f894b8754..4bf82613d440 100644 --- a/arch/mips/kvm/tlb.c +++ b/arch/mips/kvm/tlb.c @@ -282,7 +282,7 @@ int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va) if (idx >= current_cpu_data.tlbsize) BUG(); - if (idx > 0) { + if (idx >= 0) { write_c0_entryhi(UNIQUE_ENTRYHI(idx)); write_c0_entrylo0(0); write_c0_entrylo1(0); @@ -297,7 +297,7 @@ int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va) local_irq_restore(flags); - if (idx > 0) + if (idx >= 0) kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__, (va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu), idx); -- git-series 0.8.10
next prev parent reply other threads:[~2017-02-02 12:09 UTC|newest] Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-02-02 12:04 [PATCH v2 0/30] KVM: MIPS: Implement GVA page tables James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 1/30] MIPS: Move pgd_alloc() out of header James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 2/30] MIPS: Export pgd/pmd symbols for KVM James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 3/30] MIPS: uasm: Add include guards in asm/uasm.h James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 4/30] MIPS: Export some tlbex internals for KVM to use James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 5/30] KVM: MIPS: Drop partial KVM_NMI implementation James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 6/30] KVM: MIPS/MMU: Simplify ASID restoration James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 7/30] KVM: MIPS: Convert get/set_regs -> vcpu_load/put James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 8/30] KVM: MIPS/MMU: Move preempt/ASID handling to implementation James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 9/30] KVM: MIPS: Remove duplicated ASIDs from vcpu James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 10/30] KVM: MIPS: Add vcpu_run() & vcpu_reenter() callbacks James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 11/30] KVM: MIPS/T&E: Restore host asid on return to host James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 12/30] KVM: MIPS/T&E: active_mm = init_mm in guest context James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 13/30] KVM: MIPS: Wire up vcpu uninit James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 14/30] KVM: MIPS/T&E: Allocate GVA -> HPA page tables James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 15/30] KVM: MIPS/T&E: Activate GVA page tables in guest context James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 16/30] KVM: MIPS: Support NetLogic KScratch registers James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 17/30] KVM: MIPS: Add fast path TLB refill handler James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` James Hogan [this message] 2017-02-02 12:04 ` [PATCH v2 18/30] KVM: MIPS/TLB: Fix off-by-one in TLB invalidate James Hogan 2017-02-02 12:04 ` [PATCH v2 19/30] KVM: MIPS/TLB: Generalise host TLB invalidate to kernel ASID James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 20/30] KVM: MIPS/MMU: Invalidate GVA PTs on ASID changes James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 21/30] KVM: MIPS/MMU: Invalidate stale GVA PTEs on TLBW James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 22/30] KVM: MIPS/MMU: Convert KSeg0 faults to page tables James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 23/30] KVM: MIPS/MMU: Convert TLB mapped " James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 24/30] KVM: MIPS/MMU: Convert commpage fault handling " James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 25/30] KVM: MIPS: Drop vm_init() callback James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 26/30] KVM: MIPS: Use uaccess to read/modify guest instructions James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 27/30] KVM: MIPS/Emulate: Fix CACHE emulation for EVA hosts James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 28/30] KVM: MIPS/TLB: Drop kvm_local_flush_tlb_all() James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 29/30] KVM: MIPS/Emulate: Drop redundant TLB flushes on exceptions James Hogan 2017-02-02 12:04 ` James Hogan 2017-02-02 12:04 ` [PATCH v2 30/30] KVM: MIPS/MMU: Drop kvm_get_new_mmu_context() James Hogan 2017-02-02 12:04 ` James Hogan
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