aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm/vmx.c
Commit message (Collapse)AuthorAge
...
* kvm: x86: vmx: move some vmx setting from vmx_init() to hardware_setup()Tiejun Chen2014-11-07
| | | | | | | | Instead of vmx_init(), actually it would make reasonable sense to do anything specific to vmx hardware setting in vmx_x86_ops->hardware_setup(). Signed-off-by: Tiejun Chen <tiejun.chen@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: x86: vmx: move down hardware_setup() and hardware_unsetup()Tiejun Chen2014-11-07
| | | | | | | | Just move this pair of functions down to make sure later we can add something dependent on others. Signed-off-by: Tiejun Chen <tiejun.chen@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: Unavailable DR4/5 is checked before CPLNadav Amit2014-11-03
| | | | | | | | | | | | | | | | | | | | | If DR4/5 is accessed when it is unavailable (since CR4.DE is set), then #UD should be generated even if CPL>0. This is according to Intel SDM Table 6-2: "Priority Among Simultaneous Exceptions and Interrupts". Note, that this may happen on the first DR access, even if the host does not sets debug breakpoints. Obviously, it occurs when the host debugs the guest. This patch moves the DR4/5 checks from __kvm_set_dr/_kvm_get_dr to handle_dr. The emulator already checks DR4/5 availability in check_dr_read. Nested virutalization related calls to kvm_set_dr/kvm_get_dr would not like to inject exceptions to the guest. As for SVM, the patch follows the previous logic as much as possible. Anyhow, it appears the DR interception code might be buggy - even if the DR access may cause an exception, the instruction is skipped. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Clear DR7.LE during task-switchNadav Amit2014-11-03
| | | | | | | | | | | | | | | | | | | | DR7.LE should be cleared during task-switch. This feature is poorly documented. For reference, see: http://pdos.csail.mit.edu/6.828/2005/readings/i386/s12_02.htm SDM [17.2.4]: This feature is not supported in the P6 family processors, later IA-32 processors, and Intel 64 processors. AMD [2:13.1.1.4]: This bit is ignored by implementations of the AMD64 architecture. Intel's formulation could mean that it isn't even zeroed, but current hardware indeed does not behave like that. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: DR7.GD should be cleared upon any #DB exceptionNadav Amit2014-11-03
| | | | | | | | | | | | Intel SDM 17.2.4 (Debug Control Register (DR7)) says: "The processor clears the GD flag upon entering to the debug exception handler." This sentence may be misunderstood as if it happens only on #DB due to debug-register protection, but it happens regardless to the cause of the #DB. Fix the behavior to match both real hardware and Bochs. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* x86,kvm,vmx: Don't trap writes to CR4.TSDAndy Lutomirski2014-11-03
| | | | | | | | | | | | CR4.TSD is guest-owned; don't trap writes to it in VMX guests. This avoids a VM exit on context switches into or out of a PR_TSC_SIGSEGV task. I think that this fixes an unintentional side-effect of: 4c38609ac569 KVM: VMX: Make guest cr4 mask more conservative Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: defer load of APIC access page address during resetPaolo Bonzini2014-11-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Most call paths to vmx_vcpu_reset do not hold the SRCU lock. Defer loading the APIC access page to the next vmentry. This avoids the following lockdep splat: [ INFO: suspicious RCU usage. ] 3.18.0-rc2-test2+ #70 Not tainted ------------------------------- include/linux/kvm_host.h:474 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-x86/2371: #0: (&vcpu->mutex){+.+...}, at: [<ffffffffa037d800>] vcpu_load+0x20/0xd0 [kvm] stack backtrace: CPU: 4 PID: 2371 Comm: qemu-system-x86 Not tainted 3.18.0-rc2-test2+ #70 Hardware name: Dell Inc. OptiPlex 9010/0M9KCM, BIOS A12 01/10/2013 0000000000000001 ffff880209983ca8 ffffffff816f514f 0000000000000000 ffff8802099b8990 ffff880209983cd8 ffffffff810bd687 00000000000fee00 ffff880208a2c000 ffff880208a10000 ffff88020ef50040 ffff880209983d08 Call Trace: [<ffffffff816f514f>] dump_stack+0x4e/0x71 [<ffffffff810bd687>] lockdep_rcu_suspicious+0xe7/0x120 [<ffffffffa037d055>] gfn_to_memslot+0xd5/0xe0 [kvm] [<ffffffffa03807d3>] __gfn_to_pfn+0x33/0x60 [kvm] [<ffffffffa0380885>] gfn_to_page+0x25/0x90 [kvm] [<ffffffffa038aeec>] kvm_vcpu_reload_apic_access_page+0x3c/0x80 [kvm] [<ffffffffa08f0a9c>] vmx_vcpu_reset+0x20c/0x460 [kvm_intel] [<ffffffffa039ab8e>] kvm_vcpu_reset+0x15e/0x1b0 [kvm] [<ffffffffa039ac0c>] kvm_arch_vcpu_setup+0x2c/0x50 [kvm] [<ffffffffa037f7e0>] kvm_vm_ioctl+0x1d0/0x780 [kvm] [<ffffffff810bc664>] ? __lock_is_held+0x54/0x80 [<ffffffff812231f0>] do_vfs_ioctl+0x300/0x520 [<ffffffff8122ee45>] ? __fget+0x5/0x250 [<ffffffff8122f0fa>] ? __fget_light+0x2a/0xe0 [<ffffffff81223491>] SyS_ioctl+0x81/0xa0 [<ffffffff816fed6d>] system_call_fastpath+0x16/0x1b Reported-by: Takashi Iwai <tiwai@suse.de> Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com> Tested-by: Wanpeng Li <wanpeng.li@linux.intel.com> Fixes: 38b9917350cb2946e368ba684cfc33d1672f104e Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Disable preemption while reading from shadow VMCSJan Kiszka2014-11-02
| | | | | | | | | | | | | | | | | | | | | In order to access the shadow VMCS, we need to load it. At this point, vmx->loaded_vmcs->vmcs and the actually loaded one start to differ. If we now get preempted by Linux, vmx_vcpu_put and, on return, the vmx_vcpu_load will work against the wrong vmcs. That can cause copy_shadow_to_vmcs12 to corrupt the vmcs12 state. Fix the issue by disabling preemption during the copy operation. copy_vmcs12_to_shadow is safe from this issue as it is executed by vmx_vcpu_run when preemption is already disabled before vmentry. This bug is exposed by running Jailhouse within KVM on CPUs with shadow VMCS support. Jailhouse never expects an interrupt pending vmexit, but the bug can cause it if, after copy_shadow_to_vmcs12 is preempted, the active VMCS happens to have the virtual interrupt pending flag set in the CPU-based execution controls. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: x86: don't kill guest on unknown exit reasonMichael S. Tsirkin2014-10-24
| | | | | | | | | | KVM_EXIT_UNKNOWN is a kvm bug, we don't really know whether it was triggered by a priveledged application. Let's not kill the guest: WARN and inject #UD instead. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: vmx: handle invvpid vm exit gracefullyPetr Matousek2014-10-24
| | | | | | | | | | | | | | | On systems with invvpid instruction support (corresponding bit in IA32_VMX_EPT_VPID_CAP MSR is set) guest invocation of invvpid causes vm exit, which is currently not handled and results in propagation of unknown exit to userspace. Fix this by installing an invvpid vm exit handler. This is CVE-2014-3646. Cc: stable@vger.kernel.org Signed-off-by: Petr Matousek <pmatouse@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Prevent host from panicking on shared MSR writes.Andy Honig2014-10-24
| | | | | | | | | | | The previous patch blocked invalid writes directly when the MSR is written. As a precaution, prevent future similar mistakes by gracefulling handle GPs caused by writes to shared MSRs. Cc: stable@vger.kernel.org Signed-off-by: Andrew Honig <ahonig@google.com> [Remove parts obsoleted by Nadav's patch. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Check non-canonical addresses upon WRMSRNadav Amit2014-10-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Upon WRMSR, the CPU should inject #GP if a non-canonical value (address) is written to certain MSRs. The behavior is "almost" identical for AMD and Intel (ignoring MSRs that are not implemented in either architecture since they would anyhow #GP). However, IA32_SYSENTER_ESP and IA32_SYSENTER_EIP cause #GP if non-canonical address is written on Intel but not on AMD (which ignores the top 32-bits). Accordingly, this patch injects a #GP on the MSRs which behave identically on Intel and AMD. To eliminate the differences between the architecutres, the value which is written to IA32_SYSENTER_ESP and IA32_SYSENTER_EIP is turned to canonical value before writing instead of injecting a #GP. Some references from Intel and AMD manuals: According to Intel SDM description of WRMSR instruction #GP is expected on WRMSR "If the source register contains a non-canonical address and ECX specifies one of the following MSRs: IA32_DS_AREA, IA32_FS_BASE, IA32_GS_BASE, IA32_KERNEL_GS_BASE, IA32_LSTAR, IA32_SYSENTER_EIP, IA32_SYSENTER_ESP." According to AMD manual instruction manual: LSTAR/CSTAR (SYSCALL): "The WRMSR instruction loads the target RIP into the LSTAR and CSTAR registers. If an RIP written by WRMSR is not in canonical form, a general-protection exception (#GP) occurs." IA32_GS_BASE and IA32_FS_BASE (WRFSBASE/WRGSBASE): "The address written to the base field must be in canonical form or a #GP fault will occur." IA32_KERNEL_GS_BASE (SWAPGS): "The address stored in the KernelGSbase MSR must be in canonical form." This patch fixes CVE-2014-3610. Cc: stable@vger.kernel.org Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* x86,kvm,vmx: Preserve CR4 across VM entryAndy Lutomirski2014-10-18
| | | | | | | | | | | | | | | | | | | | | CR4 isn't constant; at least the TSD and PCE bits can vary. TBH, treating CR0 and CR3 as constant scares me a bit, too, but it looks like it's correct. This adds a branch and a read from cr4 to each vm entry. Because it is extremely likely that consecutive entries into the same vcpu will have the same host cr4 value, this fixes up the vmcs instead of restoring cr4 after the fact. A subsequent patch will add a kernel-wide cr4 shadow, reducing the overhead in the common case to just two memory reads and a branch. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: stable@vger.kernel.org Cc: Petr Matousek <pmatouse@redhat.com> Cc: Gleb Natapov <gleb@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for-3.18-consistent-ops' of ↵Linus Torvalds2014-10-15
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...
| * x86: Replace __get_cpu_var usesChristoph Lameter2014-08-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to __this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to __this_cpu_inc(y) Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | kvm: x86: Unpin and remove kvm_arch->apic_access_pageTang Chen2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to make the APIC access page migratable, stop pinning it in memory. And because the APIC access page is not pinned in memory, we can remove kvm_arch->apic_access_page. When we need to write its physical address into vmcs, we use gfn_to_page() to get its page struct, which is needed to call page_to_phys(); the page is then immediately unpinned. Suggested-by: Gleb Natapov <gleb@kernel.org> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: vmx: Implement set_apic_access_page_addrTang Chen2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the APIC access page is pinned by KVM for the entire life of the guest. We want to make it migratable in order to make memory hot-unplug available for machines that run KVM. This patch prepares to handle this for the case where there is no nested virtualization, or where the nested guest does not have an APIC page of its own. All accesses to kvm->arch.apic_access_page are changed to go through kvm_vcpu_reload_apic_access_page. If the APIC access page is invalidated when the host is running, we update the VMCS in the next guest entry. If it is invalidated when the guest is running, the MMU notifier will force an exit, after which we will handle everything as in the previous case. If it is invalidated when a nested guest is running, the request will update either the VMCS01 or the VMCS02. Updating the VMCS01 is done at the next L2->L1 exit, while updating the VMCS02 is done in prepare_vmcs02. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: x86: fix two typos in commentTiejun Chen2014-09-24
| | | | | | | | | | | | | | s/drity/dirty and s/vmsc01/vmcs01 Signed-off-by: Tiejun Chen <tiejun.chen@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: vmx: Inject #GP on invalid PAT CRNadav Amit2014-09-24
| | | | | | | | | | | | | | | | | | Guest which sets the PAT CR to invalid value should get a #GP. Currently, if vmx supports loading PAT CR during entry, then the value is not checked. This patch makes the required check in that case. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: directly use kvm_make_request againLiang Chen2014-09-24
| | | | | | | | | | | | | | | | A one-line wrapper around kvm_make_request is not particularly useful. Replace kvm_mmu_flush_tlb() with kvm_make_request(). Signed-off-by: Liang Chen <liangchen.linux@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: nested VMX: disable perf cpuid reportingMarcelo Tosatti2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Initilization of L2 guest with -cpu host, on L1 guest with -cpu host triggers: (qemu) KVM: entry failed, hardware error 0x7 ... nested_vmx_run: VMCS MSR_{LOAD,STORE} unsupported Nested VMX MSR load/store support is not sufficient to allow perf for L2 guest. Until properly fixed, trap CPUID and disable function 0xA. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: Make init_rmode_tss() return 0 on success.Paolo Bonzini2014-09-24
| | | | | | | | | | | | | | | | | | | | | | | | In init_rmode_tss(), there two variables indicating the return value, r and ret, and it return 0 on error, 1 on success. The function is only called by vmx_set_tss_addr(), and ret is redundant. This patch removes the redundant variable, by making init_rmode_tss() return 0 on success, -errno on failure. Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: Make init_rmode_identity_map() return 0 on success.Tang Chen2014-09-17
| | | | | | | | | | | | | | | | | | | | | | | | In init_rmode_identity_map(), there two variables indicating the return value, r and ret, and it return 0 on error, 1 on success. The function is only called by vmx_create_vcpu(), and ret is redundant. This patch removes the redundant variable, and makes init_rmode_identity_map() return 0 on success, -errno on failure. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: Remove ept_identity_pagetable from struct kvm_arch.Tang Chen2014-09-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvm_arch->ept_identity_pagetable holds the ept identity pagetable page. But it is never used to refer to the page at all. In vcpu initialization, it indicates two things: 1. indicates if ept page is allocated 2. indicates if a memory slot for identity page is initialized Actually, kvm_arch->ept_identity_pagetable_done is enough to tell if the ept identity pagetable is initialized. So we can remove ept_identity_pagetable. NOTE: In the original code, ept identity pagetable page is pinned in memroy. As a result, it cannot be migrated/hot-removed. After this patch, since kvm_arch->ept_identity_pagetable is removed, ept identity pagetable page is no longer pinned in memory. And it can be migrated/hot-removed. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Gleb Natapov <gleb@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: Use APIC_DEFAULT_PHYS_BASE macro as the apic access page address.Tang Chen2014-09-11
| | | | | | | | | | | | | | | | | | We have APIC_DEFAULT_PHYS_BASE defined as 0xfee00000, which is also the address of apic access page. So use this macro. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Reviewed-by: Gleb Natapov <gleb@kernel.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: remove garbage arg to *hardware_{en,dis}ableRadim Krčmář2014-08-29
| | | | | | | | | | | | | | | | | | | | In the beggining was on_each_cpu(), which required an unused argument to kvm_arch_ops.hardware_{en,dis}able, but this was soon forgotten. Remove unnecessary arguments that stem from this. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: fix some sparse warningsPaolo Bonzini2014-08-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sparse reports the following easily fixed warnings: arch/x86/kvm/vmx.c:8795:48: sparse: Using plain integer as NULL pointer arch/x86/kvm/vmx.c:2138:5: sparse: symbol vmx_read_l1_tsc was not declared. Should it be static? arch/x86/kvm/vmx.c:6151:48: sparse: Using plain integer as NULL pointer arch/x86/kvm/vmx.c:8851:6: sparse: symbol vmx_sched_in was not declared. Should it be static? arch/x86/kvm/svm.c:2162:5: sparse: symbol svm_read_l1_tsc was not declared. Should it be static? Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: nVMX: nested TPR shadow/threshold emulationWanpeng Li2014-08-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fix bug https://bugzilla.kernel.org/show_bug.cgi?id=61411 TPR shadow/threshold feature is important to speed up the Windows guest. Besides, it is a must feature for certain VMM. We map virtual APIC page address and TPR threshold from L1 VMCS. If TPR_BELOW_THRESHOLD VM exit is triggered by L2 guest and L1 interested in, we inject it into L1 VMM for handling. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> [Add PAGE_ALIGNED check, do not write useless virtual APIC page address if TPR shadowing is disabled. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: nVMX: introduce nested_get_vmcs12_pagesWanpeng Li2014-08-29
| | | | | | | | | | | | | | | | Introduce function nested_get_vmcs12_pages() to check the valid of nested apic access page and virtual apic page earlier. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: trace kvm_ple_window grow/shrinkRadim Krčmář2014-08-21
| | | | | | | | | | | | | | Tracepoint for dynamic PLE window, fired on every potential change. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: VMX: dynamise PLE windowRadim Krčmář2014-08-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Window is increased on every PLE exit and decreased on every sched_in. The idea is that we don't want to PLE exit if there is no preemption going on. We do this with sched_in() because it does not hold rq lock. There are two new kernel parameters for changing the window: ple_window_grow and ple_window_shrink ple_window_grow affects the window on PLE exit and ple_window_shrink does it on sched_in; depending on their value, the window is modifier like this: (ple_window is kvm_intel's global) ple_window_shrink/ | ple_window_grow | PLE exit | sched_in -------------------+--------------------+--------------------- < 1 | = ple_window | = ple_window < ple_window | *= ple_window_grow | /= ple_window_shrink otherwise | += ple_window_grow | -= ple_window_shrink A third new parameter, ple_window_max, controls the maximal ple_window; it is internally rounded down to a closest multiple of ple_window_grow. VCPU's PLE window is never allowed below ple_window. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: VMX: make PLE window per-VCPURadim Krčmář2014-08-21
| | | | | | | | | | | | | | | | | | | | Change PLE window into per-VCPU variable, seeded from module parameter, to allow greater flexibility. Brings in a small overhead on every vmentry. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: introduce sched_in to kvm_x86_opsRadim Krčmář2014-08-21
| | | | | | | | | | | | | | | | sched_in preempt notifier is available for x86, allow its use in specific virtualization technlogies as well. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: vmx: fix ept reserved bits for 1-GByte pageWanpeng Li2014-08-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | EPT misconfig handler in kvm will check which reason lead to EPT misconfiguration after vmexit. One of the reasons is that an EPT paging-structure entry is configured with settings reserved for future functionality. However, the handler can't identify if paging-structure entry of reserved bits for 1-GByte page are configured, since PDPTE which point to 1-GByte page will reserve bits 29:12 instead of bits 7:3 which are reserved for PDPTE that references an EPT Page Directory. This patch fix it by reserve bits 29:12 for 1-GByte page. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | arch/x86: Use RCU_INIT_POINTER(x, NULL) in kvm/vmx.cMonam Agarwal2014-08-19
| | | | | | | | | | | | | | | | | | | | | | Here rcu_assign_pointer() is ensuring that the initialization of a structure is carried out before storing a pointer to that structure. So, rcu_assign_pointer(p, NULL) can always safely be converted to RCU_INIT_POINTER(p, NULL). Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: drop fpu_activate hookWanpeng Li2014-08-19
|/ | | | | | | | | | | | The only user of the fpu_activate hook was dropped in commit 2d04a05bd7e9 (KVM: x86 emulator: emulate CLTS internally, 2011-04-20). vmx_fpu_activate and svm_fpu_activate are still called on #NM (and for Intel CLTS), but never from common code; hence, there's no need for a hook. Reviewed-by: Yang Zhang <yang.z.zhang@intel.com> Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Fix nested vmexit ack intr before load vmcs01Wanpeng Li2014-08-05
| | | | | | | | | | | | | | | | | | | | | An external interrupt will cause a vmexit with reason "external interrupt" when L2 is running. L1 will pick up the interrupt through vmcs12 if L1 set the ack interrupt bit. Commit 77b0f5d (KVM: nVMX: Ack and write vector info to intr_info if L1 asks us to) retrieves the interrupt that belongs to L1 before vmcs01 is loaded. This will lead to problems in the next patch, which would write to SVI of vmcs02 instead of vmcs01 (SVI of vmcs02 doesn't make sense because L2 runs without APICv). Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Liu, RongrongX <rongrongx.liu@intel.com> Tested-by: Felipe Reyes <freyes@suse.com> Fixes: 77b0f5d67ff2781f36831cba79674c3e97bd7acf Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> [Move tracepoint as well. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: remove duplicate vmx_mpx_supported() prototypeChris J Arges2014-07-30
| | | | | | | Remove a prototype which was added by both 93c4adc7afe and 36be0b9deb2. Signed-off-by: Chris J Arges <chris.j.arges@canonical.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Replace NR_VMX_MSR with its definitionPaolo Bonzini2014-07-24
| | | | | | | | Using ARRAY_SIZE directly makes it easier to read the code. While touching the code, replace the division by a multiplication in the recently added BUILD_BUG_ON. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Assertions to check no overrun in MSR listsNadav Amit2014-07-24
| | | | | | | | | | Currently there is no check whether shared MSRs list overrun the allocated size which can results in bugs. In addition there is no check that vmx->guest_msrs has sufficient space to accommodate all the VMX msrs. This patch adds the assertions. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: DR6/7.RTM cannot be writtenNadav Amit2014-07-21
| | | | | | | | | | | | | | Haswell and newer Intel CPUs have support for RTM, and in that case DR6.RTM is not fixed to 1 and DR7.RTM is not fixed to zero. That is not the case in the current KVM implementation. This bug is apparent only if the MOV-DR instruction is emulated or the host also debugs the guest. This patch is a partial fix which enables DR6.RTM and DR7.RTM to be cleared and set respectively. It also sets DR6.RTM upon every debug exception. Obviously, it is not a complete fix, as debugging of RTM is still unsupported. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: clean up nested_release_vmcs12 and code around itPaolo Bonzini2014-07-21
| | | | | | | Make nested_release_vmcs12 idempotent. Tested-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: fix lifetime issues for vmcs02Paolo Bonzini2014-07-21
| | | | | | | | | | | | | | free_nested needs the loaded_vmcs to be valid if it is a vmcs02, in order to detach it from the shadow vmcs. However, this is not available anymore after commit 26a865f4aa8e (KVM: VMX: fix use after free of vmx->loaded_vmcs, 2014-01-03). Revert that patch, and fix its problem by forcing a vmcs01 as the active VMCS before freeing all the nested VMX state. Reported-by: Wanpeng Li <wanpeng.li@linux.intel.com> Tested-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Fix virtual interrupt delivery injectionWanpeng Li2014-07-17
| | | | | | | | | | | | | | | | | This patch fix bug reported in https://bugzilla.kernel.org/show_bug.cgi?id=73331, after the patch http://www.spinics.net/lists/kvm/msg105230.html applied, there is some progress and the L2 can boot up, however, slowly. The original idea of this fix vid injection patch is from "Zhang, Yang Z" <yang.z.zhang@intel.com>. Interrupt which delivered by vid should be injected to L1 by L0 if current is in L1, or should be injected to L2 by L0 through the old injection way if L1 doesn't have set External-interrupt exiting bit. The current logic doen't consider these cases. This patch fix it by vid intr to L1 if current is L1 or L2 through old injection way if L1 doen't have External-interrupt exiting bit set. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: "Zhang, Yang Z" <yang.z.zhang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: return all bits from get_interrupt_shadowPaolo Bonzini2014-07-11
| | | | | | | | | | | | | | | | | | | For the next patch we will need to know the full state of the interrupt shadow; we will then set KVM_REQ_EVENT when one bit is cleared. However, right now get_interrupt_shadow only returns the one corresponding to the emulated instruction, or an unconditional 0 if the emulated instruction does not have an interrupt shadow. This is confusing and does not allow us to check for cleared bits as mentioned above. Clean the callback up, and modify toggle_interruptibility to match the comment above the call. As a small result, the call to set_interrupt_shadow will be skipped in the common case where int_shadow == 0 && mask == 0. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: speed up emulation of invalid guest statePaolo Bonzini2014-07-11
| | | | | | | | | | | | | | | | | | | About 25% of the time spent in emulation of invalid guest state is wasted in checking whether emulation is required for the next instruction. However, this almost never changes except when a segment register (or TR or LDTR) changes, or when there is a mode transition (i.e. CR0 changes). In fact, vmx_set_segment and vmx_set_cr0 already modify vmx->emulation_required (except that the former for some reason uses |= instead of just an assignment). So there is no need to call guest_state_valid in the emulation loop. Emulation performance test results indicate 1650-2600 cycles for common instructions, versus 2300-3200 before this patch on a Sandy Bridge Xeon. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: vmx instructions handling does not consider cs.lNadav Amit2014-06-19
| | | | | | | | | | | VMX instructions use 32-bit operands in 32-bit mode, and 64-bit operands in 64-bit mode. The current implementation is broken since it does not use the register operands correctly, and always uses 64-bit for reads and writes. Moreover, write to memory in vmwrite only considers long-mode, so it ignores cs.l. This patch fixes this behavior. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: handle_cr ignores 32/64-bit modeNadav Amit2014-06-19
| | | | | | | | | | | On 32-bit mode only bits [31:0] of the CR should be used for setting the CR value. Otherwise, the host may incorrectly assume the value is invalid if bits [63:32] are not zero. Moreover, the CR is currently being read twice when CR8 is used. Last, nested mov-cr exiting is modified to handle the CR value correctly as well. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: check DR6/7 high-bits are clear only on long-modeNadav Amit2014-06-19
| | | | | | | | | When the guest sets DR6 and DR7, KVM asserts the high 32-bits are clear, and otherwise injects a #GP exception. This exception should only be injected only if running in long-mode. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Fix returned value of MSR_IA32_VMX_VMCS_ENUMJan Kiszka2014-06-19
| | | | | | | | Many real CPUs get this wrong as well, but ours is totally off: bits 9:1 define the highest index value. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>