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2015-10-14KVM: x86: fix RSM into 64-bit protected modePaolo Bonzini
In order to get into 64-bit protected mode, you need to enable paging while EFER.LMA=1. For this to work, CS.L must be 0. Currently, we load the segments before CR0 and CR4, which means that if RSM returns into 64-bit protected mode CS.L is already 1 and everything breaks. Luckily, CS.L=0 is always the case when executing RSM, because it is forbidden to execute RSM from 64-bit protected mode. Hence it is enough to load CR0 and CR4 first, and only then the segments. Fixes: 660a5d517aaab9187f93854425c4c63f4a09195c Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-14KVM: x86: fix previous commit for 32-bitPaolo Bonzini
Unfortunately I only noticed this after pushing. Fixes: f0d648bdf0a5bbc91da6099d5282f77996558ea4 Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-13Merge branch 'kvm-master' into HEADPaolo Bonzini
This merge brings in a couple important SMM fixes, which makes it easier to test latest KVM with unrestricted_guest=0 and to test the in-progress work on SMM support in the firmware. Conflicts: arch/x86/kvm/x86.c
2015-10-13KVM: x86: fix SMI to halted VCPUPaolo Bonzini
An SMI to a halted VCPU must wake it up, hence a VCPU with a pending SMI must be considered runnable. Fixes: 64d6067057d9658acb8675afcfba549abdb7fc16 Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-13KVM: x86: clean up kvm_arch_vcpu_runnablePaolo Bonzini
Split the huge conditional in two functions. Fixes: 64d6067057d9658acb8675afcfba549abdb7fc16 Cc: stable@vger.kernel.org Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-13KVM: x86: map/unmap private slots in __x86_set_memory_regionPaolo Bonzini
Otherwise, two copies (one of them never populated and thus bogus) are allocated for the regular and SMM address spaces. This breaks SMM with EPT but without unrestricted guest support, because the SMM copy of the identity page map is all zeros. By moving the allocation to the caller we also remove the last vestiges of kernel-allocated memory regions (not accessible anymore in userspace since commit b74a07beed0e, "KVM: Remove kernel-allocated memory regions", 2010-06-21); that is a nice bonus. Reported-by: Alexandre DERUMIER <aderumier@odiso.com> Cc: stable@vger.kernel.org Fixes: 9da0e4d5ac969909f6b435ce28ea28135a9cbd69 Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-13KVM: x86: build kvm_userspace_memory_region in x86_set_memory_regionPaolo Bonzini
The next patch will make x86_set_memory_region fill the userspace_addr. Since the struct is not used untouched anymore, it makes sense to build it in x86_set_memory_region directly; it also simplifies the callers. Reported-by: Alexandre DERUMIER <aderumier@odiso.com> Cc: stable@vger.kernel.org Fixes: 9da0e4d5ac969909f6b435ce28ea28135a9cbd69 Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: Update Posted-Interrupts Descriptor when vCPU is blockedFeng Wu
This patch updates the Posted-Interrupts Descriptor when vCPU is blocked. pre-block: - Add the vCPU to the blocked per-CPU list - Set 'NV' to POSTED_INTR_WAKEUP_VECTOR post-block: - Remove the vCPU from the per-CPU list Signed-off-by: Feng Wu <feng.wu@intel.com> [Concentrate invocation of pre/post-block hooks to vcpu_block. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: Update Posted-Interrupts Descriptor when vCPU is preemptedFeng Wu
This patch updates the Posted-Interrupts Descriptor when vCPU is preempted. sched out: - Set 'SN' to suppress furture non-urgent interrupts posted for the vCPU. sched in: - Clear 'SN' - Change NDST if vCPU is scheduled to a different CPU - Set 'NV' to POSTED_INTR_VECTOR Signed-off-by: Feng Wu <feng.wu@intel.com> [Include asm/cpu.h to fix !CONFIG_SMP compilation. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: select IRQ_BYPASS_MANAGERFeng Wu
Select IRQ_BYPASS_MANAGER for x86 when CONFIG_KVM is set Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: Update IRTE for posted-interruptsFeng Wu
This patch adds the routine to update IRTE for posted-interrupts when guest changes the interrupt configuration. Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> [Squashed in automatically generated patch from the build robot "KVM: x86: vcpu_to_pi_desc() can be static" - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: make kvm_set_msi_irq() publicFeng Wu
Make kvm_set_msi_irq() public, we can use this function outside. Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: Define a new interface kvm_intr_is_single_vcpu()Feng Wu
This patch defines a new interface kvm_intr_is_single_vcpu(), which can returns whether the interrupt is for single-CPU or not. It is used by VT-d PI, since now we only support single-CPU interrupts, For lowest-priority interrupts, if user configures it via /proc/irq or uses irqbalance to make it single-CPU, we can use PI to deliver the interrupts to it. Full functionality of lowest-priority support will be added later. Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: Add some helper functions for Posted-InterruptsFeng Wu
This patch adds some helper functions to manipulate the Posted-Interrupts Descriptor. Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> [Make the new functions inline. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: Extend struct pi_desc for VT-d Posted-InterruptsFeng Wu
Extend struct pi_desc for VT-d Posted-Interrupts. Signed-off-by: Feng Wu <feng.wu@intel.com> Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: drop rdtscp_enabled fieldXiao Guangrong
Check cpuid bit instead of it Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: clean up bit operation on SECONDARY_VM_EXEC_CONTROLXiao Guangrong
Use vmcs_set_bits() and vmcs_clear_bits() to clean up the code Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: unify SECONDARY_VM_EXEC_CONTROL updateXiao Guangrong
Unify the update in vmx_cpuid_update() Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> [Rewrite to use vmcs_set_secondary_exec_control. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: align vmx->nested.nested_vmx_secondary_ctls_high to ↵Paolo Bonzini
vmx->rdtscp_enabled The SECONDARY_EXEC_RDTSCP must be available iff RDTSCP is enabled in the guest. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: simplify invpcid handling in vmx_cpuid_update()Xiao Guangrong
If vmx_invpcid_supported() is true, second execution control filed must be supported and SECONDARY_EXEC_ENABLE_INVPCID must have already been set in current vmcs by vmx_secondary_exec_control() If vmx_invpcid_supported() is false, no need to clear SECONDARY_EXEC_ENABLE_INVPCID Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: simplify rdtscp handling in vmx_cpuid_update()Xiao Guangrong
if vmx_rdtscp_supported() is true SECONDARY_EXEC_RDTSCP must have already been set in current vmcs by vmx_secondary_exec_control() Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: VMX: drop rdtscp_enabled check in prepare_vmcs02()Xiao Guangrong
SECONDARY_EXEC_RDTSCP set for L2 guest comes from vmcs12 Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: add pcommit supportXiao Guangrong
Pass PCOMMIT CPU feature to guest to enable PCOMMIT instruction Currently we do not catch pcommit instruction for L1 guest and allow L1 to catch this instruction for L2 if, as required by the spec, L1 can enumerate the PCOMMIT instruction via CPUID: | IA32_VMX_PROCBASED_CTLS2[53] (which enumerates support for the | 1-setting of PCOMMIT exiting) is always the same as | CPUID.07H:EBX.PCOMMIT[bit 22]. Thus, software can set PCOMMIT exiting | to 1 if and only if the PCOMMIT instruction is enumerated via CPUID The spec can be found at https://software.intel.com/sites/default/files/managed/0d/53/319433-022.pdf Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: allow guest to use cflushopt and clwbXiao Guangrong
Pass these CPU features to guest to enable them in guest They are needed by nvdimm drivers Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: vmx: disable posted interrupts if no local APICPaolo Bonzini
Uniprocessor 32-bit randconfigs can disable the local APIC, and posted interrupts require reserving a vector on the LAPIC, so they are incompatible. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01kvm/x86: Hyper-V HV_X64_MSR_VP_RUNTIME supportAndrey Smetanin
HV_X64_MSR_VP_RUNTIME msr used by guest to get "the time the virtual processor consumes running guest code, and the time the associated logical processor spends running hypervisor code on behalf of that guest." Calculation of this time is performed by task_cputime_adjusted() for vcpu task. Necessary to support loading of winhv.sys in guest, which in turn is required to support Windows VMBus. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Gleb Natapov <gleb@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01kvm/x86: Hyper-V HV_X64_MSR_VP_INDEX export for QEMU.Andrey Smetanin
Insert Hyper-V HV_X64_MSR_VP_INDEX into msr's emulated list, so QEMU can set Hyper-V features cpuid HV_X64_MSR_VP_INDEX_AVAILABLE bit correctly. KVM emulation part is in place already. Necessary to support loading of winhv.sys in guest, which in turn is required to support Windows VMBus. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Gleb Natapov <gleb@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01kvm/x86: Hyper-V HV_X64_MSR_RESET msrAndrey Smetanin
HV_X64_MSR_RESET msr is used by Hyper-V based Windows guest to reset guest VM by hypervisor. Necessary to support loading of winhv.sys in guest, which in turn is required to support Windows VMBus. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Gleb Natapov <gleb@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01kvm: add tracepoint for fast mmioJason Wang
Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: Add support for local interrupt requests from userspaceSteve Rutherford
In order to enable userspace PIC support, the userspace PIC needs to be able to inject local interrupts even when the APICs are in the kernel. KVM_INTERRUPT now supports sending local interrupts to an APIC when APICs are in the kernel. The ready_for_interrupt_request flag is now only set when the CPU/APIC will immediately accept and inject an interrupt (i.e. APIC has not masked the PIC). When the PIC wishes to initiate an INTA cycle with, say, CPU0, it kicks CPU0 out of the guest, and renedezvous with CPU0 once it arrives in userspace. When the CPU/APIC unmasks the PIC, a KVM_EXIT_IRQ_WINDOW_OPEN is triggered, so that userspace has a chance to inject a PIC interrupt if it had been pending. Overall, this design can lead to a small number of spurious userspace renedezvous. In particular, whenever the PIC transistions from low to high while it is masked and whenever the PIC becomes unmasked while it is low. Note: this does not buffer more than one local interrupt in the kernel, so the VMM needs to enter the guest in order to complete interrupt injection before injecting an additional interrupt. Compiles for x86. Can pass the KVM Unit Tests. Signed-off-by: Steve Rutherford <srutherford@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: Add EOI exit bitmap inferenceSteve Rutherford
In order to support a userspace IOAPIC interacting with an in kernel APIC, the EOI exit bitmaps need to be configurable. If the IOAPIC is in userspace (i.e. the irqchip has been split), the EOI exit bitmaps will be set whenever the GSI Routes are configured. In particular, for the low MSI routes are reservable for userspace IOAPICs. For these MSI routes, the EOI Exit bit corresponding to the destination vector of the route will be set for the destination VCPU. The intention is for the userspace IOAPICs to use the reservable MSI routes to inject interrupts into the guest. This is a slight abuse of the notion of an MSI Route, given that MSIs classically bypass the IOAPIC. It might be worthwhile to add an additional route type to improve clarity. Compile tested for Intel x86. Signed-off-by: Steve Rutherford <srutherford@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: Add KVM exit for IOAPIC EOIsSteve Rutherford
Adds KVM_EXIT_IOAPIC_EOI which allows the kernel to EOI level-triggered IOAPIC interrupts. Uses a per VCPU exit bitmap to decide whether or not the IOAPIC needs to be informed (which is identical to the EOI_EXIT_BITMAP field used by modern x86 processors, but can also be used to elide kvm IOAPIC EOI exits on older processors). [Note: A prototype using ResampleFDs found that decoupling the EOI from the VCPU's thread made it possible for the VCPU to not see a recent EOI after reentering the guest. This does not match real hardware.] Compile tested for Intel x86. Signed-off-by: Steve Rutherford <srutherford@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: Split the APIC from the rest of IRQCHIP.Steve Rutherford
First patch in a series which enables the relocation of the PIC/IOAPIC to userspace. Adds capability KVM_CAP_SPLIT_IRQCHIP; KVM_CAP_SPLIT_IRQCHIP enables the construction of LAPICs without the rest of the irqchip. Compile tested for x86. Signed-off-by: Steve Rutherford <srutherford@google.com> Suggested-by: Andrew Honig <ahonig@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: unify handling of interrupt windowPaolo Bonzini
The interrupt window is currently checked twice, once in vmx.c/svm.c and once in dm_request_for_irq_injection. The only difference is the extra check for kvm_arch_interrupt_allowed in dm_request_for_irq_injection, and the different return value (EINTR/KVM_EXIT_INTR for vmx.c/svm.c vs. 0/KVM_EXIT_IRQ_WINDOW_OPEN for dm_request_for_irq_injection). However, dm_request_for_irq_injection is basically dead code! Revive it by removing the checks in vmx.c and svm.c's vmexit handlers, and fixing the returned values for the dm_request_for_irq_injection case. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: introduce lapic_in_kernelPaolo Bonzini
Avoid pointer chasing and memory barriers, and simplify the code when split irqchip (LAPIC in kernel, IOAPIC/PIC in userspace) is introduced. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: replace vm_has_apicv hook with cpu_uses_apicvPaolo Bonzini
This will avoid an unnecessary trip to ->kvm and from there to the VPIC. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: store IOAPIC-handled vectors in each VCPUPaolo Bonzini
We can reuse the algorithm that computes the EOI exit bitmap to figure out which vectors are handled by the IOAPIC. The only difference between the two is for edge-triggered interrupts other than IRQ8 that have no notifiers active; however, the IOAPIC does not have to do anything special for these interrupts anyway. This again limits the interactions between the IOAPIC and the LAPIC, making it easier to move the former to userspace. Inspired by a patch from Steve Rutherford. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01KVM: x86: set TMR when the interrupt is acceptedPaolo Bonzini
Do not compute TMR in advance. Instead, set the TMR just before the interrupt is accepted into the IRR. This limits the coupling between IOAPIC and LAPIC. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01Use WARN_ON_ONCE for missing X86_FEATURE_NRIPSDirk Müller
The cpu feature flags are not ever going to change, so warning everytime can cause a lot of kernel log spam (in our case more than 10GB/hour). The warning seems to only occur when nested virtualization is enabled, so it's probably triggered by a KVM bug. This is a sensible and safe change anyway, and the KVM bug fix might not be suitable for stable releases anyway. Cc: stable@vger.kernel.org Signed-off-by: Dirk Mueller <dmueller@suse.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01Revert "KVM: SVM: use NPT page attributes"Paolo Bonzini
This reverts commit 3c2e7f7de3240216042b61073803b61b9b3cfb22. Initializing the mapping from MTRR to PAT values was reported to fail nondeterministically, and it also caused extremely slow boot (due to caching getting disabled---bug 103321) with assigned devices. Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de> Reported-by: Sebastian Schuette <dracon@ewetel.net> Cc: stable@vger.kernel.org # 4.2+ Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01Revert "KVM: svm: handle KVM_X86_QUIRK_CD_NW_CLEARED in svm_get_mt_mask"Paolo Bonzini
This reverts commit 5492830370171b6a4ede8a3bfba687a8d0f25fa5. It builds on the commit that is being reverted next. Cc: stable@vger.kernel.org # 4.2+ Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01Revert "KVM: SVM: Sync g_pat with guest-written PAT value"Paolo Bonzini
This reverts commit e098223b789b4a618dacd79e5e0dad4a9d5018d1, which has a dependency on other commits being reverted. Cc: stable@vger.kernel.org # 4.2+ Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01Revert "KVM: x86: apply guest MTRR virtualization on host reserved pages"Paolo Bonzini
This reverts commit fd717f11015f673487ffc826e59b2bad69d20fe5. It was reported to cause Machine Check Exceptions (bug 104091). Reported-by: harn-solo@gmx.de Cc: stable@vger.kernel.org # 4.2+ Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-28Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock ↵Radim Krčmář
system MSR" Shifting pvclock_vcpu_time_info.system_time on write to KVM system time MSR is a change of ABI. Probably only 2.6.16 based SLES 10 breaks due to its custom enhancements to kvmclock, but KVM never declared the MSR only for one-shot initialization. (Doc says that only one write is needed.) This reverts commit b7e60c5aedd2b63f16ef06fde4f81ca032211bc5. And adds a note to the definition of PVCLOCK_COUNTS_FROM_ZERO. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-25KVM: x86: fix off-by-one in reserved bits checkPaolo Bonzini
29ecd6601904 ("KVM: x86: avoid uninitialized variable warning", 2015-09-06) introduced a not-so-subtle problem, which probably escaped review because it was not part of the patch context. Before the patch, leaf was always equal to iterator.level. After, it is equal to iterator.level - 1 in the call to is_shadow_zero_bits_set, and when is_shadow_zero_bits_set does another "-1" the check on reserved bits becomes incorrect. Using "iterator.level" in the call fixes this call trace: WARNING: CPU: 2 PID: 17000 at arch/x86/kvm/mmu.c:3385 handle_mmio_page_fault.part.93+0x1a/0x20 [kvm]() Modules linked in: tun sha256_ssse3 sha256_generic drbg binfmt_misc ipv6 vfat fat fuse dm_crypt dm_mod kvm_amd kvm crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd fam15h_power amd64_edac_mod k10temp edac_core amdkfd amd_iommu_v2 radeon acpi_cpufreq [...] Call Trace: dump_stack+0x4e/0x84 warn_slowpath_common+0x95/0xe0 warn_slowpath_null+0x1a/0x20 handle_mmio_page_fault.part.93+0x1a/0x20 [kvm] tdp_page_fault+0x231/0x290 [kvm] ? emulator_pio_in_out+0x6e/0xf0 [kvm] kvm_mmu_page_fault+0x36/0x240 [kvm] ? svm_set_cr0+0x95/0xc0 [kvm_amd] pf_interception+0xde/0x1d0 [kvm_amd] handle_exit+0x181/0xa70 [kvm_amd] ? kvm_arch_vcpu_ioctl_run+0x68b/0x1730 [kvm] kvm_arch_vcpu_ioctl_run+0x6f6/0x1730 [kvm] ? kvm_arch_vcpu_ioctl_run+0x68b/0x1730 [kvm] ? preempt_count_sub+0x9b/0xf0 ? mutex_lock_killable_nested+0x26f/0x490 ? preempt_count_sub+0x9b/0xf0 kvm_vcpu_ioctl+0x358/0x710 [kvm] ? __fget+0x5/0x210 ? __fget+0x101/0x210 do_vfs_ioctl+0x2f4/0x560 ? __fget_light+0x29/0x90 SyS_ioctl+0x4c/0x90 entry_SYSCALL_64_fastpath+0x16/0x73 ---[ end trace 37901c8686d84de6 ]--- Reported-by: Borislav Petkov <bp@alien8.de> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-25KVM: x86: use correct page table format to check nested page table reserved bitsPaolo Bonzini
Intel CPUID on AMD host or vice versa is a weird case, but it can happen. Handle it by checking the host CPU vendor instead of the guest's in reset_tdp_shadow_zero_bits_mask. For speed, the check uses the fact that Intel EPT has an X (executable) bit while AMD NPT has NX. Reported-by: Borislav Petkov <bp@alien8.de> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-25KVM: svm: do not call kvm_set_cr0 from init_vmcbPaolo Bonzini
kvm_set_cr0 may want to call kvm_zap_gfn_range and thus access the memslots array (SRCU protected). Using a mini SRCU critical section is ugly, and adding it to kvm_arch_vcpu_create doesn't work because the VMX vcpu_create callback calls synchronize_srcu. Fixes this lockdep splat: =============================== [ INFO: suspicious RCU usage. ] 4.3.0-rc1+ #1 Not tainted ------------------------------- include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by qemu-system-i38/17000: #0: (&(&kvm->mmu_lock)->rlock){+.+...}, at: kvm_zap_gfn_range+0x24/0x1a0 [kvm] [...] Call Trace: dump_stack+0x4e/0x84 lockdep_rcu_suspicious+0xfd/0x130 kvm_zap_gfn_range+0x188/0x1a0 [kvm] kvm_set_cr0+0xde/0x1e0 [kvm] init_vmcb+0x760/0xad0 [kvm_amd] svm_create_vcpu+0x197/0x250 [kvm_amd] kvm_arch_vcpu_create+0x47/0x70 [kvm] kvm_vm_ioctl+0x302/0x7e0 [kvm] ? __lock_is_held+0x51/0x70 ? __fget+0x101/0x210 do_vfs_ioctl+0x2f4/0x560 ? __fget_light+0x29/0x90 SyS_ioctl+0x4c/0x90 entry_SYSCALL_64_fastpath+0x16/0x73 Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-21KVM: x86: trap AMD MSRs for the TSeg base and maskPaolo Bonzini
These have roughly the same purpose as the SMRR, which we do not need to implement in KVM. However, Linux accesses MSR_K8_TSEG_ADDR at boot, which causes problems when running a Xen dom0 under KVM. Just return 0, meaning that processor protection of SMRAM is not in effect. Reported-by: M A Young <m.a.young@durham.ac.uk> Cc: stable@vger.kernel.org Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-18kvm: svm: reset mmu on VCPU resetIgor Mammedov
When INIT/SIPI sequence is sent to VCPU which before that was in use by OS, VMRUN might fail with: KVM: entry failed, hardware error 0xffffffff EAX=00000000 EBX=00000000 ECX=00000000 EDX=000006d3 ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000 EIP=00000000 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =0000 00000000 0000ffff 00009300 CS =9a00 0009a000 0000ffff 00009a00 [...] CR0=60000010 CR2=b6f3e000 CR3=01942000 CR4=000007e0 [...] EFER=0000000000000000 with corresponding SVM error: KVM: FAILED VMRUN WITH VMCB: [...] cpl: 0 efer: 0000000000001000 cr0: 0000000080010010 cr2: 00007fd7fe85bf90 cr3: 0000000187d0c000 cr4: 0000000000000020 [...] What happens is that VCPU state right after offlinig: CR0: 0x80050033 EFER: 0xd01 CR4: 0x7e0 -> long mode with CR3 pointing to longmode page tables and when VCPU gets INIT/SIPI following transition happens CR0: 0 -> 0x60000010 EFER: 0x0 CR4: 0x7e0 -> paging disabled with stale CR3 However SVM under the hood puts VCPU in Paged Real Mode* which effectively translates CR0 0x60000010 -> 80010010 after svm_vcpu_reset() -> init_vmcb() -> kvm_set_cr0() -> svm_set_cr0() but from kvm_set_cr0() perspective CR0: 0 -> 0x60000010 only caching bits are changed and commit d81135a57aa6 ("KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed")' regressed svm_vcpu_reset() which relied on MMU being reset. As result VMRUN after svm_vcpu_reset() tries to run VCPU in Paged Real Mode with stale MMU context (longmode page tables), which causes some AMD CPUs** to bail out with VMEXIT_INVALID. Fix issue by unconditionally resetting MMU context at init_vmcb() time. * AMD64 Architecture Programmer’s Manual, Volume 2: System Programming, rev: 3.25 15.19 Paged Real Mode ** Opteron 1216 Signed-off-by: Igor Mammedov <imammedo@redhat.com> Fixes: d81135a57aa6 Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-16KVM: vmx: fix VPID is 0000H in non-root operationWanpeng Li
Reference SDM 28.1: The current VPID is 0000H in the following situations: - Outside VMX operation. (This includes operation in system-management mode under the default treatment of SMIs and SMM with VMX operation; see Section 34.14.) - In VMX root operation. - In VMX non-root operation when the “enable VPID” VM-execution control is 0. The VPID should never be 0000H in non-root operation when "enable VPID" VM-execution control is 1. However, commit 34a1cd60 ("kvm: x86: vmx: move some vmx setting from vmx_init() to hardware_setup()") remove the codes which reserve 0000H for VMX root operation. This patch fix it by again reserving 0000H for VMX root operation. Cc: stable@vger.kernel.org # 3.19+ Fixes: 34a1cd60d17f62c1f077c1478a6c2ca8c3d17af4 Reported-by: Wincy Van <fanwenyi0529@gmail.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
generated by cgit (git 2.34.1) at 2025-09-14 00:46:18 +0000