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* KVM: x86: select IRQ_BYPASS_MANAGERFeng Wu2015-10-013-0/+56
| | | | | | | | 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>
* KVM: x86: Update IRTE for posted-interruptsFeng Wu2015-10-014-0/+121
| | | | | | | | | | | | 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>
* KVM: make kvm_set_msi_irq() publicFeng Wu2015-10-012-2/+7
| | | | | | | | | 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>
* KVM: Define a new interface kvm_intr_is_single_vcpu()Feng Wu2015-10-014-0/+91
| | | | | | | | | | | | | | | 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>
* KVM: Add some helper functions for Posted-InterruptsFeng Wu2015-10-011-0/+26
| | | | | | | | | | | 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>
* KVM: Extend struct pi_desc for VT-d Posted-InterruptsFeng Wu2015-10-011-2/+18
| | | | | | | | 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>
* irq_remapping: move structs outside #ifdefPaolo Bonzini2015-10-011-5/+5
| | | | | | | | | This is friendlier to clients of the code, who are going to prepare vcpu_data structs unconditionally, even if CONFIG_IRQ_REMAP is not defined. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* x86: kvmclock: abolish PVCLOCK_COUNTS_FROM_ZERORadim Krčmář2015-10-011-11/+35
| | | | | | | | | | | | | | | | | | | | | | | | Newer KVM won't be exposing PVCLOCK_COUNTS_FROM_ZERO anymore. The purpose of that flags was to start counting system time from 0 when the KVM clock has been initialized. We can achieve the same by selecting one read as the initial point. A simple subtraction will work unless the KVM clock count overflows earlier (has smaller width) than scheduler's cycle count. We should be safe till x86_128. Because PVCLOCK_COUNTS_FROM_ZERO was enabled only on new hypervisors, setting sched clock as stable based on PVCLOCK_TSC_STABLE_BIT might regress on older ones. I presume we don't need to change kvm_clock_read instead of introducing kvm_sched_clock_read. A problem could arise in case sched_clock is expected to return the same value as get_cycles, but we should have merged those clocks in that case. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: VMX: drop rdtscp_enabled fieldXiao Guangrong2015-10-012-11/+14
| | | | | | | Check cpuid bit instead of it Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: VMX: clean up bit operation on SECONDARY_VM_EXEC_CONTROLXiao Guangrong2015-10-011-17/+6Star
| | | | | | | 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>
* KVM: VMX: unify SECONDARY_VM_EXEC_CONTROL updateXiao Guangrong2015-10-011-10/+25
| | | | | | | | 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>
* KVM: VMX: align vmx->nested.nested_vmx_secondary_ctls_high to ↵Paolo Bonzini2015-10-011-3/+8
| | | | | | | | | 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>
* KVM: VMX: simplify invpcid handling in vmx_cpuid_update()Xiao Guangrong2015-10-011-12/+5Star
| | | | | | | | | | | | | 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>
* KVM: VMX: simplify rdtscp handling in vmx_cpuid_update()Xiao Guangrong2015-10-011-9/+8Star
| | | | | | | | | 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>
* KVM: VMX: drop rdtscp_enabled check in prepare_vmcs02()Xiao Guangrong2015-10-011-2/+1Star
| | | | | | | 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>
* KVM: x86: add pcommit supportXiao Guangrong2015-10-015-8/+42
| | | | | | | | | | | | | | | | | | 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>
* KVM: x86: allow guest to use cflushopt and clwbXiao Guangrong2015-10-011-1/+1
| | | | | | | | | 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>
* KVM: vmx: disable posted interrupts if no local APICPaolo Bonzini2015-10-011-1/+2
| | | | | | | | 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>
* kvm/x86: Hyper-V HV_X64_MSR_VP_RUNTIME supportAndrey Smetanin2015-10-014-2/+24
| | | | | | | | | | | | | | | | | | | | 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>
* kvm/x86: Hyper-V HV_X64_MSR_VP_INDEX export for QEMU.Andrey Smetanin2015-10-011-0/+1
| | | | | | | | | | | | | | | | 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>
* kvm/x86: Hyper-V HV_X64_MSR_RESET msrAndrey Smetanin2015-10-013-0/+20
| | | | | | | | | | | | | | | 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>
* kvm: add tracepoint for fast mmioJason Wang2015-10-013-0/+20
| | | | | | | 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>
* KVM: x86: Add support for local interrupt requests from userspaceSteve Rutherford2015-10-014-15/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* KVM: x86: Add EOI exit bitmap inferenceSteve Rutherford2015-10-015-3/+54
| | | | | | | | | | | | | | | | | | | | | | | 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>
* KVM: x86: Add KVM exit for IOAPIC EOIsSteve Rutherford2015-10-013-7/+30
| | | | | | | | | | | | | | | | | | | | 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>
* KVM: x86: Split the APIC from the rest of IRQCHIP.Steve Rutherford2015-10-017-7/+56
| | | | | | | | | | | | | | | | 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>
* KVM: x86: unify handling of interrupt windowPaolo Bonzini2015-10-013-26/+2Star
| | | | | | | | | | | | | | 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>
* KVM: x86: introduce lapic_in_kernelPaolo Bonzini2015-10-017-43/+45
| | | | | | | | 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>
* KVM: x86: replace vm_has_apicv hook with cpu_uses_apicvPaolo Bonzini2015-10-016-9/+15
| | | | | | This will avoid an unnecessary trip to ->kvm and from there to the VPIC. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: store IOAPIC-handled vectors in each VCPUPaolo Bonzini2015-10-017-34/+18Star
| | | | | | | | | | | | | | | 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>
* KVM: x86: set TMR when the interrupt is acceptedPaolo Bonzini2015-10-015-23/+14Star
| | | | | | | 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>
* Merge branch 'x86/for-kvm' of ↵Paolo Bonzini2015-10-011-55/+55
|\ | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into HEAD This merges a cleanup of asm/apic.h, which is needed by the KVM patches to support VT-d posted interrupts. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * x86/x2apic: Make stub functions available even if !CONFIG_X86_LOCAL_APICPaolo Bonzini2015-09-301-55/+55
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some CONFIG_X86_X2APIC functions, especially x2apic_enabled(), are not declared if !CONFIG_X86_LOCAL_APIC. However, the same stubs that work for !CONFIG_X86_X2APIC are okay even if there is no local APIC support at all. Avoid the introduction of #ifdefs by moving the x2apic declarations completely outside the CONFIG_X86_LOCAL_APIC block. (Unfortunately, diff generation messes up the actual change that this patch makes). There is no semantic change because CONFIG_X86_X2APIC depends on CONFIG_X86_LOCAL_APIC. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Feng Wu <feng.wu@intel.com> Link: http://lkml.kernel.org/r/1443435991-35750-1-git-send-email-pbonzini@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Use WARN_ON_ONCE for missing X86_FEATURE_NRIPSDirk Müller2015-10-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | Revert "KVM: SVM: use NPT page attributes"Paolo Bonzini2015-10-011-96/+5Star
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | Revert "KVM: svm: handle KVM_X86_QUIRK_CD_NW_CLEARED in svm_get_mt_mask"Paolo Bonzini2015-10-011-8/+7Star
| | | | | | | | | | | | | | | | 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>
* | Revert "KVM: SVM: Sync g_pat with guest-written PAT value"Paolo Bonzini2015-10-011-10/+0Star
| | | | | | | | | | | | | | | | 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>
* | Revert "KVM: x86: apply guest MTRR virtualization on host reserved pages"Paolo Bonzini2015-10-012-5/+13
| | | | | | | | | | | | | | | | | | 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>
* | Revert "KVM: x86: zero kvmclock_offset when vcpu0 initializes kvmclock ↵Radim Krčmář2015-09-282-4/+1Star
|/ | | | | | | | | | | | | | | | | 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>
* Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2015-09-272-5/+27
|\ | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Thomas Gleixner: "Two bugfixes from Andy addressing at least some of the subtle NMI related wreckage which has been reported by Sasha Levin" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/nmi/64: Fix a paravirt stack-clobbering bug in the NMI code x86/paravirt: Replace the paravirt nop with a bona fide empty function
| * x86/nmi/64: Fix a paravirt stack-clobbering bug in the NMI codeAndy Lutomirski2015-09-221-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The NMI entry code that switches to the normal kernel stack needs to be very careful not to clobber any extra stack slots on the NMI stack. The code is fine under the assumption that SWAPGS is just a normal instruction, but that assumption isn't really true. Use SWAPGS_UNSAFE_STACK instead. This is part of a fix for some random crashes that Sasha saw. Fixes: 9b6e6a8334d5 ("x86/nmi/64: Switch stacks on userspace NMI entry") Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/974bc40edffdb5c2950a5c4977f821a446b76178.1442791737.git.luto@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86/paravirt: Replace the paravirt nop with a bona fide empty functionAndy Lutomirski2015-09-222-4/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PARAVIRT_ADJUST_EXCEPTION_FRAME generates this code (using nmi as an example, trimmed for readability): ff 15 00 00 00 00 callq *0x0(%rip) # 2796 <nmi+0x6> 2792: R_X86_64_PC32 pv_irq_ops+0x2c That's a call through a function pointer to regular C function that does nothing on native boots, but that function isn't protected against kprobes, isn't marked notrace, and is certainly not guaranteed to preserve any registers if the compiler is feeling perverse. This is bad news for a CLBR_NONE operation. Of course, if everything works correctly, once paravirt ops are patched, it gets nopped out, but what if we hit this code before paravirt ops are patched in? This can potentially cause breakage that is very difficult to debug. A more subtle failure is possible here, too: if _paravirt_nop uses the stack at all (even just to push RBP), it will overwrite the "NMI executing" variable if it's called in the NMI prologue. The Xen case, perhaps surprisingly, is fine, because it's already written in asm. Fix all of the cases that default to paravirt_nop (including adjust_exception_frame) with a big hammer: replace paravirt_nop with an asm function that is just a ret instruction. The Xen case may have other problems, so document them. This is part of a fix for some random crashes that Sasha saw. Reported-and-tested-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Andy Lutomirski <luto@kernel.org> Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/8f5d2ba295f9d73751c33d97fda03e0495d9ade0.1442791737.git.luto@kernel.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Merge tag 'pci-v4.3-fixes-1' of ↵Linus Torvalds2015-09-251-0/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI fixes from Bjorn Helgaas: "These are fixes for things we merged for v4.3 (VPD, MSI, and bridge window management), and a new Renesas R8A7794 SoC device ID. Details: Resource management: - Revert pci_read_bridge_bases() unification (Bjorn Helgaas) - Clear IORESOURCE_UNSET when clipping a bridge window (Bjorn Helgaas) MSI: - Fix MSI IRQ domains for VFs on virtual buses (Alex Williamson) Renesas R-Car host bridge driver: - Add R8A7794 support (Sergei Shtylyov) Miscellaneous: - Fix devfn for VPD access through function 0 (Alex Williamson) - Use function 0 VPD only for identical functions (Alex Williamson)" * tag 'pci-v4.3-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI: rcar: Add R8A7794 support PCI: Use function 0 VPD for identical functions, regular VPD for others PCI: Fix devfn for VPD access through function 0 PCI/MSI: Fix MSI IRQ domains for VFs on virtual buses PCI: Clear IORESOURCE_UNSET when clipping a bridge window PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code"
| * | PCI: Revert "PCI: Call pci_read_bridge_bases() from core instead of arch code"Bjorn Helgaas2015-09-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert dff22d2054b5 ("PCI: Call pci_read_bridge_bases() from core instead of arch code"). Reading PCI bridge windows is not arch-specific in itself, but there is PCI core code that doesn't work correctly if we read them too early. For example, Hannes found this case on an ARM Freescale i.mx6 board: pci_bus 0000:00: root bus resource [mem 0x01000000-0x01efffff] pci 0000:00:00.0: PCI bridge to [bus 01-ff] pci 0000:00:00.0: BAR 8: no space for [mem size 0x01000000] (mem window) pci 0000:01:00.0: BAR 2: failed to assign [mem size 0x00200000] pci 0000:01:00.0: BAR 1: failed to assign [mem size 0x00004000] pci 0000:01:00.0: BAR 0: failed to assign [mem size 0x00000100] The 00:00.0 mem window needs to be at least 3MB: the 01:00.0 device needs 0x204100 of space, and mem windows are megabyte-aligned. Bus sizing can increase a bridge window size, but never *decrease* it (see d65245c3297a ("PCI: don't shrink bridge resources")). Prior to dff22d2054b5, ARM didn't read bridge windows at all, so the "original size" was zero, and we assigned a 3MB window. After dff22d2054b5, we read the bridge windows before sizing the bus. The firmware programmed a 16MB window (size 0x01000000) in 00:00.0, and since we never decrease the size, we kept 16MB even though we only needed 3MB. But 16MB doesn't fit in the host bridge aperture, so we failed to assign space for the window and the downstream devices. I think this is a defect in the PCI core: we shouldn't rely on the firmware to assign sensible windows. Ray reported a similar problem, also on ARM, with Broadcom iProc. Issues like this are too hard to fix right now, so revert dff22d2054b5. Reported-by: Hannes <oe5hpm@gmail.com> Reported-by: Ray Jui <rjui@broadcom.com> Link: http://lkml.kernel.org/r/CAAa04yFQEUJm7Jj1qMT57-LG7ZGtnhNDBe=PpSRa70Mj+XhW-A@mail.gmail.com Link: http://lkml.kernel.org/r/55F75BB8.4070405@broadcom.com Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
* | | Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2015-09-255-8/+25
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM fixes from Paolo Bonzini: "AMD fixes for bugs introduced in the 4.2 merge window, and a few PPC bug fixes too" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: disable halt_poll_ns as default for s390x KVM: x86: fix off-by-one in reserved bits check KVM: x86: use correct page table format to check nested page table reserved bits KVM: svm: do not call kvm_set_cr0 from init_vmcb KVM: x86: trap AMD MSRs for the TSeg base and mask KVM: PPC: Book3S: Take the kvm->srcu lock in kvmppc_h_logical_ci_load/store() KVM: PPC: Book3S HV: Pass the correct trap argument to kvmhv_commence_exit KVM: PPC: Book3S HV: Fix handling of interrupted VCPUs kvm: svm: reset mmu on VCPU reset
| * | | KVM: disable halt_poll_ns as default for s390xDavid Hildenbrand2015-09-251-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We observed some performance degradation on s390x with dynamic halt polling. Until we can provide a proper fix, let's enable halt_poll_ns as default only for supported architectures. Architectures are now free to set their own halt_poll_ns default value. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * | | KVM: x86: fix off-by-one in reserved bits checkPaolo Bonzini2015-09-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | KVM: x86: use correct page table format to check nested page table reserved bitsPaolo Bonzini2015-09-251-6/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | KVM: svm: do not call kvm_set_cr0 from init_vmcbPaolo Bonzini2015-09-251-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | KVM: x86: trap AMD MSRs for the TSeg base and maskPaolo Bonzini2015-09-212-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-07-16 21:28:31 +0200