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| * | KVM: x86 emulator: implement MMX MOVQ (opcodes 0f 6f, 0f 7f)Avi Kivity2012-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | Needed by some framebuffer drivers. See https://bugzilla.kernel.org/show_bug.cgi?id=42779 Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: x86 emulator: MMX supportAvi Kivity2012-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | General support for the MMX instruction set. Special care is taken to trap pending x87 exceptions so that they are properly reflected to the guest. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: x86 emulator: implement movntpsAvi Kivity2012-04-16
| | | | | | | | | | | | | | | | | | | | | Used to write to framebuffers (by at least Icaros). Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: x86: emulate movdqaStefan Hajnoczi2012-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | An Ubuntu 9.10 Karmic Koala guest is unable to boot or install due to missing movdqa emulation: kvm_exit: reason EXCEPTION_NMI rip 0x7fef3e025a7b info 7fef3e799000 80000b0e kvm_page_fault: address 7fef3e799000 error_code f kvm_emulate_insn: 0:7fef3e025a7b: 66 0f 7f 07 (prot64) movdqa %xmm0,(%rdi) [avi: mark it explicitly aligned] Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: x86 emulator: add support for vector alignmentAvi Kivity2012-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | x86 defines three classes of vector instructions: explicitly aligned (#GP(0) if unaligned, explicitly unaligned, and default (which depends on the encoding: AVX is unaligned, SSE is aligned). Add support for marking an instruction as explicitly aligned or unaligned, and mark MOVDQU as unaligned. Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: SVM: Auto-load on CPUs with SVMJosh Triplett2012-04-16
| | | | | | | | | | | | | | | | | | | | | | | | Enable x86 feature-based autoloading for the kvm-amd module on CPUs with X86_FEATURE_SVM. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: MMU: Improve iteration through sptes from rmapTakuya Yoshikawa2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Iteration using rmap_next(), the actual body is pte_list_next(), is inefficient: every time we call it we start from checking whether rmap holds a single spte or points to a descriptor which links more sptes. In the case of shadow paging, this quadratic total iteration cost is a problem. Even for two dimensional paging, with EPT/NPT on, in which we almost always have a single mapping, the extra checks at the end of the iteration should be eliminated. This patch fixes this by introducing rmap_iterator which keeps the iteration context for the next search. Furthermore the implementation of rmap_next() is splitted into two functions, rmap_get_first() and rmap_get_next(), to avoid repeatedly checking whether the rmap being iterated on has only one spte. Although there seemed to be only a slight change for EPT/NPT, the actual improvement was significant: we observed that GET_DIRTY_LOG for 1GB dirty memory became 15% faster than before. This is probably because the new code is easy to make branch predictions. Note: we just remove pte_list_next() because we can think of parent_ptes as a reverse mapping. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: MMU: Make pte_list_desc fit cache lines wellTakuya Yoshikawa2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have PTE_LIST_EXT + 1 pointers in this structure and these 40/20 bytes do not fit cache lines well. Furthermore, some allocators may use 64/32-byte objects for the pte_list_desc cache. This patch solves this problem by changing PTE_LIST_EXT from 4 to 3. For shadow paging, the new size is still large enough to hold both the kernel and process mappings for usual anonymous pages. For file mappings, there may be a slight change in the cache usage. Note: with EPT/NPT we almost always have a single spte in each reverse mapping and we will not see any change by this. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: x86: add paging gcc optimizationDavidlohr Bueso2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | Since most guests will have paging enabled for memory management, add likely() optimization around CR0.PG checks. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: VMX: Auto-load on CPUs with VMXJosh Triplett2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | Enable x86 feature-based autoloading for the kvm-intel module on CPUs with X86_FEATURE_VMX. Signed-off-by: Josh Triplett <josh@joshtriplett.org> Acked-By: Kay Sievers <kay@vrfy.org> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: Switch to srcu-less get_dirty_log()Takuya Yoshikawa2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have seen some problems of the current implementation of get_dirty_log() which uses synchronize_srcu_expedited() for updating dirty bitmaps; e.g. it is noticeable that this sometimes gives us ms order of latency when we use VGA displays. Furthermore the recent discussion on the following thread "srcu: Implement call_srcu()" http://lkml.org/lkml/2012/1/31/211 also motivated us to implement get_dirty_log() without SRCU. This patch achieves this goal without sacrificing the performance of both VGA and live migration: in practice the new code is much faster than the old one unless we have too many dirty pages. Implementation: The key part of the implementation is the use of xchg() operation for clearing dirty bits atomically. Since this allows us to update only BITS_PER_LONG pages at once, we need to iterate over the dirty bitmap until every dirty bit is cleared again for the next call. Although some people may worry about the problem of using the atomic memory instruction many times to the concurrently accessible bitmap, it is usually accessed with mmu_lock held and we rarely see concurrent accesses: so what we need to care about is the pure xchg() overheads. Another point to note is that we do not use for_each_set_bit() to check which ones in each BITS_PER_LONG pages are actually dirty. Instead we simply use __ffs() in a loop. This is much faster than repeatedly call find_next_bit(). Performance: The dirty-log-perf unit test showed nice improvements, some times faster than before, except for some extreme cases; for such cases the speed of getting dirty page information is much faster than we process it in the userspace. For real workloads, both VGA and live migration, we have observed pure improvements: when the guest was reading a file during live migration, we originally saw a few ms of latency, but with the new method the latency was less than 200us. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: Avoid checking huge page mappings in get_dirty_log()Takuya Yoshikawa2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Dropped such mappings when we enabled dirty logging and we will never create new ones until we stop the logging. For this we introduce a new function which can be used to write protect a range of PT level pages: although we do not need to care about a range of pages at this point, the following patch will need this feature to optimize the write protection of many pages. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: MMU: Split the main body of rmap_write_protect() off from othersTakuya Yoshikawa2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We will use this in the following patch to implement another function which needs to write protect pages using the rmap information. Note that there is a small change in debug printing for large pages: we do not differentiate them from others to avoid duplicating code. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: x86: Add ioctl for KVM_KVMCLOCK_CTRLEric B Munson2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that we have a flag that will tell the guest it was suspended, create an interface for that communication using a KVM ioctl. Signed-off-by: Eric B Munson <emunson@mgebm.net> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: Factor out kvm_vcpu_kick to arch-generic codeChristoffer Dall2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kvm_vcpu_kick function performs roughly the same funcitonality on most all architectures, so we shouldn't have separate copies. PowerPC keeps a pointer to interchanging waitqueues on the vcpu_arch structure and to accomodate this special need a __KVM_HAVE_ARCH_VCPU_GET_WQ define and accompanying function kvm_arch_vcpu_wq have been defined. For all other architectures this is a generic inline that just returns &vcpu->wq; Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: SVM: count all irq windows exitJason Wang2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also count the exits of fast-path. Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Joerg Roedel <joerg.roedel@amd.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * | KVM: x86: expose Intel cpu new features (HLE, RTM) to guestLiu, Jinsong2012-04-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Intel recently release 2 new features, HLE and RTM. Refer to http://software.intel.com/file/41417. This patch expose them to guest. Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* | | KVM: ensure async PF event wakes up vcpu from haltGleb Natapov2012-05-06
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If vcpu executes hlt instruction while async PF is waiting to be delivered vcpu can block and deliver async PF only after another even wakes it up. This happens because kvm_check_async_pf_completion() will remove completion event from vcpu->async_pf.done before entering kvm_vcpu_block() and this will make kvm_arch_vcpu_runnable() return false. The solution is to make vcpu runnable when processing completion. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* | | kill mm argument of vm_munmap()Al Viro2012-04-21
| | | | | | | | | | | | | | | | | | it's always current->mm Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | VM: add "vm_mmap()" helper functionLinus Torvalds2012-04-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This continues the theme started with vm_brk() and vm_munmap(): vm_mmap() does the same thing as do_mmap(), but additionally does the required VM locking. This uninlines (and rewrites it to be clearer) do_mmap(), which sadly duplicates it in mm/mmap.c and mm/nommu.c. But that way we don't have to export our internal do_mmap_pgoff() function. Some day we hopefully don't have to export do_mmap() either, if all modular users can become the simpler vm_mmap() instead. We're actually very close to that already, with the notable exception of the (broken) use in i810, and a couple of stragglers in binfmt_elf. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | VM: add "vm_munmap()" helper functionLinus Torvalds2012-04-20
| |/ |/| | | | | | | | | | | Like the vm_brk() function, this is the same as "do_munmap()", except it does the VM locking for the caller. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | KVM: VMX: Fix kvm_set_shared_msr() called in preemptible contextAvi Kivity2012-04-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvm_set_shared_msr() may not be called in preemptible context, but vmx_set_msr() does so: BUG: using smp_processor_id() in preemptible [00000000] code: qemu-kvm/22713 caller is kvm_set_shared_msr+0x32/0xa0 [kvm] Pid: 22713, comm: qemu-kvm Not tainted 3.4.0-rc3+ #39 Call Trace: [<ffffffff8131fa82>] debug_smp_processor_id+0xe2/0x100 [<ffffffffa0328ae2>] kvm_set_shared_msr+0x32/0xa0 [kvm] [<ffffffffa03a103b>] vmx_set_msr+0x28b/0x2d0 [kvm_intel] ... Making kvm_set_shared_msr() work in preemptible is cleaner, but it's used in the fast path. Making two variants is overkill, so this patch just disables preemption around the call. Reported-by: Dave Jones <davej@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* | KVM: PMU emulation: GLOBAL_CTRL MSR should be enabled on resetGleb Natapov2012-04-10
|/ | | | | | | On reset all MPU counters should be enabled in GLOBAL_CTRL MSR. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: VMX: vmx_set_cr0 expects kvm->srcu lockedMarcelo Tosatti2012-04-05
| | | | | | | | vmx_set_cr0 is called from vcpu run context, therefore it expects kvm->srcu to be held (for setting up the real-mode TSS). Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* KVM: PMU: Fix integer constant is too large warning in kvm_pmu_set_msr()Sasikantha babu2012-04-05
| | | | | Signed-off-by: Sasikantha babu <sasikanth.v19@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
* Merge branch 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2012-03-28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm updates from Avi Kivity: "Changes include timekeeping improvements, support for assigning host PCI devices that share interrupt lines, s390 user-controlled guests, a large ppc update, and random fixes." This is with the sign-off's fixed, hopefully next merge window we won't have rebased commits. * 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (130 commits) KVM: Convert intx_mask_lock to spin lock KVM: x86: fix kvm_write_tsc() TSC matching thinko x86: kvmclock: abstract save/restore sched_clock_state KVM: nVMX: Fix erroneous exception bitmap check KVM: Ignore the writes to MSR_K7_HWCR(3) KVM: MMU: make use of ->root_level in reset_rsvds_bits_mask KVM: PMU: add proper support for fixed counter 2 KVM: PMU: Fix raw event check KVM: PMU: warn when pin control is set in eventsel msr KVM: VMX: Fix delayed load of shared MSRs KVM: use correct tlbs dirty type in cmpxchg KVM: Allow host IRQ sharing for assigned PCI 2.3 devices KVM: Ensure all vcpus are consistent with in-kernel irqchip settings KVM: x86 emulator: Allow PM/VM86 switch during task switch KVM: SVM: Fix CPL updates KVM: x86 emulator: VM86 segments must have DPL 3 KVM: x86 emulator: Fix task switch privilege checks arch/powerpc/kvm/book3s_hv.c: included linux/sched.h twice KVM: x86 emulator: correctly mask pmc index bits in RDPMC instruction emulation KVM: mmu_notifier: Flush TLBs before releasing mmu_lock ...
| * KVM: x86: fix kvm_write_tsc() TSC matching thinkoMarcelo Tosatti2012-03-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvm_write_tsc() converts from guest TSC to microseconds, not nanoseconds as intended. The result is that the window for matching is 1000 seconds, not 1 second. Microsecond precision is enough for checking whether the TSC write delta is within the heuristic values, so use it instead of nanoseconds. Noted by Avi Kivity. Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: nVMX: Fix erroneous exception bitmap checkNadav Har'El2012-03-08
| | | | | | | | | | | | | | | | | | | | The code which checks whether to inject a pagefault to L1 or L2 (in nested VMX) was wrong, incorrect in how it checked the PF_VECTOR bit. Thanks to Dan Carpenter for spotting this. Signed-off-by: Nadav Har'El <nyh@il.ibm.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Ignore the writes to MSR_K7_HWCR(3)Nicolae Mogoreanu2012-03-08
| | | | | | | | | | | | | | | | | | | | When CPUID Fn8000_0001_EAX reports 0x00100f22 Windows 7 x64 guest tries to set bit 3 in MSRC001_0015 in nt!KiDisableCacheErrataSource and fails. This patch will ignore this step and allow things to move on without having to fake CPUID value. Signed-off-by: Nicolae Mogoreanu <mogoreanu@gmail.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: MMU: make use of ->root_level in reset_rsvds_bits_maskDavidlohr Bueso2012-03-08
| | | | | | | | | | | | | | | | The reset_rsvds_bits_mask() function can use the guest walker's root level number instead of using a separate 'level' variable. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: PMU: add proper support for fixed counter 2Gleb Natapov2012-03-08
| | | | | | | | | | | | | | | | | | Currently pmu emulation emulates fixed counter 2 as bus cycles architectural counter, but since commit 9c1497ea591b25d perf has pseudo encoding for it. Use it. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: PMU: Fix raw event checkGleb Natapov2012-03-08
| | | | | | | | | | | | | | | | If eventsel has EDGE, INV or CMASK set we should create raw counter for it, but the check is done on a wrong variable. Fix it. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: PMU: warn when pin control is set in eventsel msrGleb Natapov2012-03-08
| | | | | | | | | | | | | | | | Print warning once if pin control bit is set in eventsel msr since emulation does not support it yet. Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: VMX: Fix delayed load of shared MSRsAvi Kivity2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Shared MSRs (MSR_*STAR and related) are stored in both vmx->guest_msrs and in the CPU registers, but vmx_set_msr() only updated memory. Prior to 46199f33c2953, this didn't matter, since we called vmx_load_host_state(), which scheduled a vmx_save_host_state(), which re-synchronized the CPU state, but now we don't, so the CPU state will not be synchronized until the next exit to host userspace. This mostly affects nested vmx workloads, which play with these MSRs a lot. Fix by loading the MSR eagerly. Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Allow host IRQ sharing for assigned PCI 2.3 devicesJan Kiszka2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PCI 2.3 allows to generically disable IRQ sources at device level. This enables us to share legacy IRQs of such devices with other host devices when passing them to a guest. The new IRQ sharing feature introduced here is optional, user space has to request it explicitly. Moreover, user space can inform us about its view of PCI_COMMAND_INTX_DISABLE so that we can avoid unmasking the interrupt and signaling it if the guest masked it via the virtualized PCI config space. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Acked-by: Alex Williamson <alex.williamson@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Ensure all vcpus are consistent with in-kernel irqchip settingsAvi Kivity2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If some vcpus are created before KVM_CREATE_IRQCHIP, then irqchip_in_kernel() and vcpu->arch.apic will be inconsistent, leading to potential NULL pointer dereferences. Fix by: - ensuring that no vcpus are installed when KVM_CREATE_IRQCHIP is called - ensuring that a vcpu has an apic if it is installed after KVM_CREATE_IRQCHIP This is somewhat long winded because vcpu->arch.apic is created without kvm->lock held. Based on earlier patch by Michael Ellerman. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: x86 emulator: Allow PM/VM86 switch during task switchKevin Wolf2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | Task switches can switch between Protected Mode and VM86. The current mode must be updated during the task switch emulation so that the new segment selectors are interpreted correctly. In order to let privilege checks succeed, rflags needs to be updated in the vcpu struct as this causes a CPL update. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: SVM: Fix CPL updatesKevin Wolf2012-03-08
| | | | | | | | | | | | | | | | Keep CPL at 0 in real mode and at 3 in VM86. In protected/long mode, use RPL rather than DPL of the code segment. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: x86 emulator: VM86 segments must have DPL 3Kevin Wolf2012-03-08
| | | | | | | | | | | | | | | | Setting the segment DPL to 0 for at least the VM86 code segment makes the VM entry fail on VMX. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: x86 emulator: Fix task switch privilege checksKevin Wolf2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | Currently, all task switches check privileges against the DPL of the TSS. This is only correct for jmp/call to a TSS. If a task gate is used, the DPL of this take gate is used for the check instead. Exceptions, external interrupts and iret shouldn't perform any check. [avi: kill kvm-kmod remnants] Signed-off-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: x86 emulator: correctly mask pmc index bits in RDPMC instruction emulationGleb Natapov2012-03-08
| | | | | | | | | | Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Introduce kvm_memory_slot::arch and move lpage_info into itTakuya Yoshikawa2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | Some members of kvm_memory_slot are not used by every architecture. This patch is the first step to make this difference clear by introducing kvm_memory_slot::arch; lpage_info is moved into it. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Introduce gfn_to_index() which returns the index for a given levelTakuya Yoshikawa2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch cleans up the code and removes the "(void)level;" warning suppressor. Note that we can also use this for PT_PAGE_TABLE_LEVEL to treat every level uniformly later. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Fix write protection race during dirty loggingTakuya Yoshikawa2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a race introduced by: commit 95d4c16ce78cb6b7549a09159c409d52ddd18dae KVM: Optimize dirty logging by rmap_write_protect() During protecting pages for dirty logging, other threads may also try to protect a page in mmu_sync_children() or kvm_mmu_get_page(). In such a case, because get_dirty_log releases mmu_lock before flushing TLB's, the following race condition can happen: A (get_dirty_log) B (another thread) lock(mmu_lock) clear pte.w unlock(mmu_lock) lock(mmu_lock) pte.w is already cleared unlock(mmu_lock) skip TLB flush return ... TLB flush Though thread B assumes the page has already been protected when it returns, the remaining TLB entry will break that assumption. This patch fixes this problem by making get_dirty_log hold the mmu_lock until it flushes the TLB's. Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: VMX: remove yield_on_hltRaghavendra K T2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | yield_on_hlt was introduced for CPU bandwidth capping. Now it is redundant with CFS hardlimit. yield_on_hlt also complicates the scenario in paravirtual environment, that needs to trap halt. for e.g. paravirtualized ticket spinlocks. Acked-by: Anthony Liguori <aliguori@us.ibm.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Track TSC synchronization in generationsZachary Amsden2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | This allows us to track the original nanosecond and counter values at each phase of TSC writing by the guest. This gets us perfect offset matching for stable TSC systems, and perfect software computed TSC matching for machines with unstable TSC. Signed-off-by: Zachary Amsden <zamsden@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Dont mark TSC unstable due to S4 suspendZachary Amsden2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During a host suspend, TSC may go backwards, which KVM interprets as an unstable TSC. Technically, KVM should not be marking the TSC unstable, which causes the TSC clocksource to go bad, but we need to be adjusting the TSC offsets in such a case. Dealing with this issue is a little tricky as the only place we can reliably do it is before much of the timekeeping infrastructure is up and running. On top of this, we are not in a KVM thread context, so we may not be able to safely access VCPU fields. Instead, we compute our best known hardware offset at power-up and stash it to be applied to all VCPUs when they actually start running. Signed-off-by: Zachary Amsden <zamsden@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Allow adjust_tsc_offset to be in host or guest cyclesMarcelo Tosatti2012-03-08
| | | | | | | | | | | | | | | | | | | | Redefine the API to take a parameter indicating whether an adjustment is in host or guest cycles. Signed-off-by: Zachary Amsden <zamsden@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Add last_host_tsc tracking back to KVMZachary Amsden2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The variable last_host_tsc was removed from upstream code. I am adding it back for two reasons. First, it is unnecessary to use guest TSC computation to conclude information about the host TSC. The guest may set the TSC backwards (this case handled by the previous patch), but the computation of guest TSC (and fetching an MSR) is significanlty more work and complexity than simply reading the hardware counter. In addition, we don't actually need the guest TSC for any part of the computation, by always recomputing the offset, we can eliminate the need to deal with the current offset and any scaling factors that may apply. The second reason is that later on, we are going to be using the host TSC value to restore TSC offsets after a host S4 suspend, so we need to be reading the host values, not the guest values here. Signed-off-by: Zachary Amsden <zamsden@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
| * KVM: Fix last_guest_tsc / tsc_offset semanticsZachary Amsden2012-03-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The variable last_guest_tsc was being used as an ad-hoc indicator that guest TSC has been initialized and recorded correctly. However, it may not have been, it could be that guest TSC has been set to some large value, the back to a small value (by, say, a software reboot). This defeats the logic and causes KVM to falsely assume that the guest TSC has gone backwards, marking the host TSC unstable, which is undesirable behavior. In addition, rather than try to compute an offset adjustment for the TSC on unstable platforms, just recompute the whole offset. This allows us to get rid of one callsite for adjust_tsc_offset, which is problematic because the units it takes are in guest units, but here, the computation was originally being done in host units. Doing this, and also recording last_guest_tsc when the TSC is written allow us to remove the tricky logic which depended on last_guest_tsc being zero to indicate a reset of uninitialized value. Instead, we now have the guarantee that the guest TSC offset is always at least something which will get us last_guest_tsc. Signed-off-by: Zachary Amsden <zamsden@gmail.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Avi Kivity <avi@redhat.com>
generated by cgit v1.2.2 (git 2.25.0) at 2025-04-24 16:27:05 -0400