From baa035227b2e8b4bfba8f6176dc06c60477f1634 Mon Sep 17 00:00:00 2001 From: Tiejun Chen Date: Tue, 23 Dec 2014 16:21:11 +0800 Subject: kvm: x86: vmx: reorder some msr writing The commit 34a1cd60d17f, "x86: vmx: move some vmx setting from vmx_init() to hardware_setup()", tried to refactor some codes specific to vmx hardware setting into hardware_setup(), but some msr writing should depend on our previous setting condition like enable_apicv, enable_ept and so on. Reported-by: Jamie Heilman Tested-by: Jamie Heilman Signed-off-by: Tiejun Chen Signed-off-by: Paolo Bonzini --- arch/x86/kvm/vmx.c | 88 +++++++++++++++++++++++++++--------------------------- 1 file changed, 44 insertions(+), 44 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index feb852b04598..d4c58d884838 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -5840,53 +5840,10 @@ static __init int hardware_setup(void) memset(vmx_msr_bitmap_legacy, 0xff, PAGE_SIZE); memset(vmx_msr_bitmap_longmode, 0xff, PAGE_SIZE); - vmx_disable_intercept_for_msr(MSR_FS_BASE, false); - vmx_disable_intercept_for_msr(MSR_GS_BASE, false); - vmx_disable_intercept_for_msr(MSR_KERNEL_GS_BASE, true); - vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_CS, false); - vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_ESP, false); - vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false); - vmx_disable_intercept_for_msr(MSR_IA32_BNDCFGS, true); - - memcpy(vmx_msr_bitmap_legacy_x2apic, - vmx_msr_bitmap_legacy, PAGE_SIZE); - memcpy(vmx_msr_bitmap_longmode_x2apic, - vmx_msr_bitmap_longmode, PAGE_SIZE); - - if (enable_apicv) { - for (msr = 0x800; msr <= 0x8ff; msr++) - vmx_disable_intercept_msr_read_x2apic(msr); - - /* According SDM, in x2apic mode, the whole id reg is used. - * But in KVM, it only use the highest eight bits. Need to - * intercept it */ - vmx_enable_intercept_msr_read_x2apic(0x802); - /* TMCCT */ - vmx_enable_intercept_msr_read_x2apic(0x839); - /* TPR */ - vmx_disable_intercept_msr_write_x2apic(0x808); - /* EOI */ - vmx_disable_intercept_msr_write_x2apic(0x80b); - /* SELF-IPI */ - vmx_disable_intercept_msr_write_x2apic(0x83f); - } - - if (enable_ept) { - kvm_mmu_set_mask_ptes(0ull, - (enable_ept_ad_bits) ? VMX_EPT_ACCESS_BIT : 0ull, - (enable_ept_ad_bits) ? VMX_EPT_DIRTY_BIT : 0ull, - 0ull, VMX_EPT_EXECUTABLE_MASK); - ept_set_mmio_spte_mask(); - kvm_enable_tdp(); - } else - kvm_disable_tdp(); - - update_ple_window_actual_max(); - if (setup_vmcs_config(&vmcs_config) < 0) { r = -EIO; goto out7; - } + } if (boot_cpu_has(X86_FEATURE_NX)) kvm_enable_efer_bits(EFER_NX); @@ -5945,6 +5902,49 @@ static __init int hardware_setup(void) if (nested) nested_vmx_setup_ctls_msrs(); + vmx_disable_intercept_for_msr(MSR_FS_BASE, false); + vmx_disable_intercept_for_msr(MSR_GS_BASE, false); + vmx_disable_intercept_for_msr(MSR_KERNEL_GS_BASE, true); + vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_CS, false); + vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_ESP, false); + vmx_disable_intercept_for_msr(MSR_IA32_SYSENTER_EIP, false); + vmx_disable_intercept_for_msr(MSR_IA32_BNDCFGS, true); + + memcpy(vmx_msr_bitmap_legacy_x2apic, + vmx_msr_bitmap_legacy, PAGE_SIZE); + memcpy(vmx_msr_bitmap_longmode_x2apic, + vmx_msr_bitmap_longmode, PAGE_SIZE); + + if (enable_apicv) { + for (msr = 0x800; msr <= 0x8ff; msr++) + vmx_disable_intercept_msr_read_x2apic(msr); + + /* According SDM, in x2apic mode, the whole id reg is used. + * But in KVM, it only use the highest eight bits. Need to + * intercept it */ + vmx_enable_intercept_msr_read_x2apic(0x802); + /* TMCCT */ + vmx_enable_intercept_msr_read_x2apic(0x839); + /* TPR */ + vmx_disable_intercept_msr_write_x2apic(0x808); + /* EOI */ + vmx_disable_intercept_msr_write_x2apic(0x80b); + /* SELF-IPI */ + vmx_disable_intercept_msr_write_x2apic(0x83f); + } + + if (enable_ept) { + kvm_mmu_set_mask_ptes(0ull, + (enable_ept_ad_bits) ? VMX_EPT_ACCESS_BIT : 0ull, + (enable_ept_ad_bits) ? VMX_EPT_DIRTY_BIT : 0ull, + 0ull, VMX_EPT_EXECUTABLE_MASK); + ept_set_mmio_spte_mask(); + kvm_enable_tdp(); + } else + kvm_disable_tdp(); + + update_ple_window_actual_max(); + return alloc_kvm_area(); out7: -- cgit v1.2.3 From a629df7eadffb03e6ce4a8616e62ea29fdf69b6b Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 22 Dec 2014 10:43:39 +0100 Subject: kvm: x86: drop severity of "generation wraparound" message Since most virtual machines raise this message once, it is a bit annoying. Make it KERN_DEBUG severity. Cc: stable@vger.kernel.org Fixes: 7a2e8aaf0f6873b47bc2347f216ea5b0e4c258ab Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 10fbed126b11..f83fc6c5e0ba 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4448,7 +4448,7 @@ void kvm_mmu_invalidate_mmio_sptes(struct kvm *kvm) * zap all shadow pages. */ if (unlikely(kvm_current_mmio_generation(kvm) == 0)) { - printk_ratelimited(KERN_INFO "kvm: zapping shadow pages for mmio generation wraparound\n"); + printk_ratelimited(KERN_DEBUG "kvm: zapping shadow pages for mmio generation wraparound\n"); kvm_mmu_invalidate_zap_all_pages(kvm); } } -- cgit v1.2.3 From efbeec7098eee2b3d2359d0cc24bbba0436e7f21 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sat, 27 Dec 2014 18:01:00 +0100 Subject: kvm: fix sorting of memslots with base_gfn == 0 Before commit 0e60b0799fed (kvm: change memslot sorting rule from size to GFN, 2014-12-01), the memslots' sorting key was npages, meaning that a valid memslot couldn't have its sorting key equal to zero. On the other hand, a valid memslot can have base_gfn == 0, and invalid memslots are identified by base_gfn == npages == 0. Because of this, commit 0e60b0799fed broke the invariant that invalid memslots are at the end of the mslots array. When a memslot with base_gfn == 0 was created, any invalid memslot before it were left in place. This can be fixed by changing the insertion to use a ">=" comparison instead of "<=", but some care is needed to avoid breaking the case of deleting a memslot; see the comment in update_memslots. Thanks to Tiejun Chen for posting an initial patch for this bug. Reported-by: Jamie Heilman Reported-by: Andy Lutomirski Tested-by: Jamie Heilman Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index f5283438ee05..050974c051b5 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -687,11 +687,23 @@ static void update_memslots(struct kvm_memslots *slots, slots->id_to_index[mslots[i].id] = i; i++; } - while (i > 0 && - new->base_gfn > mslots[i - 1].base_gfn) { - mslots[i] = mslots[i - 1]; - slots->id_to_index[mslots[i].id] = i; - i--; + + /* + * The ">=" is needed when creating a slot with base_gfn == 0, + * so that it moves before all those with base_gfn == npages == 0. + * + * On the other hand, if new->npages is zero, the above loop has + * already left i pointing to the beginning of the empty part of + * mslots, and the ">=" would move the hole backwards in this + * case---which is wrong. So skip the loop when deleting a slot. + */ + if (new->npages) { + while (i > 0 && + new->base_gfn >= mslots[i - 1].base_gfn) { + mslots[i] = mslots[i - 1]; + slots->id_to_index[mslots[i].id] = i; + i--; + } } mslots[i] = *new; -- cgit v1.2.3 From dbaff30940d6ef9bfa5f1f0c819cf3344ed3129f Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sat, 27 Dec 2014 21:08:16 +0100 Subject: kvm: warn on more invariant breakage Modifying a non-existent slot is not allowed. Also check that the first loop doesn't move a deleted slot beyond the used part of the mslots array. Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 050974c051b5..1cc6e2e19982 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -671,6 +671,7 @@ static void update_memslots(struct kvm_memslots *slots, WARN_ON(mslots[i].id != id); if (!new->npages) { + WARN_ON(!mslots[i].npages); new->base_gfn = 0; if (mslots[i].npages) slots->used_slots--; @@ -704,7 +705,8 @@ static void update_memslots(struct kvm_memslots *slots, slots->id_to_index[mslots[i].id] = i; i--; } - } + } else + WARN_ON_ONCE(i != slots->used_slots); mslots[i] = *new; slots->id_to_index[mslots[i].id] = i; -- cgit v1.2.3