- 14 3月, 2013 1 次提交
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由 Takuya Yoshikawa 提交于
This will be used not to zap unrelated mmu pages when creating/moving a memory slot later. Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: NGleb Natapov <gleb@redhat.com>
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- 13 3月, 2013 1 次提交
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由 Jan Kiszka 提交于
A VCPU sending INIT or SIPI to some other VCPU races for setting the remote VCPU's mp_state. When we were unlucky, KVM_MP_STATE_INIT_RECEIVED was overwritten by kvm_emulate_halt and, thus, got lost. This introduces APIC events for those two signals, keeping them in kvm_apic until kvm_apic_accept_events is run over the target vcpu context. kvm_apic_has_events reports to kvm_arch_vcpu_runnable if there are pending events, thus if vcpu blocking should end. The patch comes with the side effect of effectively obsoleting KVM_MP_STATE_SIPI_RECEIVED. We still accept it from user space, but immediately translate it to KVM_MP_STATE_INIT_RECEIVED + KVM_APIC_SIPI. The vcpu itself will no longer enter the KVM_MP_STATE_SIPI_RECEIVED state. That also means we no longer exit to user space after receiving a SIPI event. Furthermore, we already reset the VCPU on INIT, only fixing up the code segment later on when SIPI arrives. Moreover, we fix INIT handling for the BSP: it never enter wait-for-SIPI but directly starts over on INIT. Tested-by: NPaolo Bonzini <pbonzini@redhat.com> Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com> Signed-off-by: NGleb Natapov <gleb@redhat.com>
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- 12 3月, 2013 1 次提交
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由 Jan Kiszka 提交于
Neither vmx nor svm nor the common part may generate an error on kvm_vcpu_reset. So drop the return code. Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com> Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com> Signed-off-by: NGleb Natapov <gleb@redhat.com>
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- 29 1月, 2013 2 次提交
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由 Yang Zhang 提交于
Virtual interrupt delivery avoids KVM to inject vAPIC interrupts manually, which is fully taken care of by the hardware. This needs some special awareness into existing interrupr injection path: - for pending interrupt, instead of direct injection, we may need update architecture specific indicators before resuming to guest. - A pending interrupt, which is masked by ISR, should be also considered in above update action, since hardware will decide when to inject it at right time. Current has_interrupt and get_interrupt only returns a valid vector from injection p.o.v. Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NKevin Tian <kevin.tian@intel.com> Signed-off-by: NYang Zhang <yang.z.zhang@Intel.com> Signed-off-by: NGleb Natapov <gleb@redhat.com>
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由 Yang Zhang 提交于
basically to benefit from apicv, we need to enable virtualized x2apic mode. Currently, we only enable it when guest is really using x2apic. Also, clear MSR bitmap for corresponding x2apic MSRs when guest enabled x2apic: 0x800 - 0x8ff: no read intercept for apicv register virtualization, except APIC ID and TMCCT which need software's assistance to get right value. Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NKevin Tian <kevin.tian@intel.com> Signed-off-by: NYang Zhang <yang.z.zhang@Intel.com> Signed-off-by: NGleb Natapov <gleb@redhat.com>
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- 22 1月, 2013 1 次提交
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由 Xiao Guangrong 提交于
The current reexecute_instruction can not well detect the failed instruction emulation. It allows guest to retry all the instructions except it accesses on error pfn For example, some cases are nested-write-protect - if the page we want to write is used as PDE but it chains to itself. Under this case, we should stop the emulation and report the case to userspace Reviewed-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 14 1月, 2013 1 次提交
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由 Takuya Yoshikawa 提交于
Not needed any more. Reviewed-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NTakuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: NGleb Natapov <gleb@redhat.com>
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- 14 12月, 2012 3 次提交
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由 Alex Williamson 提交于
With the 3 private slots, this gives us a nice round 128 slots total. The primary motivation for this is to support more assigned devices. Each assigned device can theoretically use up to 8 slots (6 MMIO BARs, 1 ROM BAR, 1 spare for a split MSI-X table mapping) though it's far more typical for a device to use 3-4 slots. If we assume a typical VM uses a dozen slots for non-assigned devices purposes, we should always be able to support 14 worst case assigned devices or 28 to 37 typical devices. Reviewed-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NAlex Williamson <alex.williamson@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Alex Williamson 提交于
Seems like everyone copied x86 and defined 4 private memory slots that never actually get used. Even x86 only uses 3 of the 4. These aren't exposed so there's no need to add padding. Reviewed-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NAlex Williamson <alex.williamson@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Alex Williamson 提交于
It's easy to confuse KVM_MEMORY_SLOTS and KVM_MEM_SLOTS_NUM. One is the user accessible slots and the other is user + private. Make this more obvious. Reviewed-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NAlex Williamson <alex.williamson@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 01 12月, 2012 2 次提交
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由 Will Auld 提交于
CPUID.7.0.EBX[1]=1 indicates IA32_TSC_ADJUST MSR 0x3b is supported Basic design is to emulate the MSR by allowing reads and writes to a guest vcpu specific location to store the value of the emulated MSR while adding the value to the vmcs tsc_offset. In this way the IA32_TSC_ADJUST value will be included in all reads to the TSC MSR whether through rdmsr or rdtsc. This is of course as long as the "use TSC counter offsetting" VM-execution control is enabled as well as the IA32_TSC_ADJUST control. However, because hardware will only return the TSC + IA32_TSC_ADJUST + vmsc tsc_offset for a guest process when it does and rdtsc (with the correct settings) the value of our virtualized IA32_TSC_ADJUST must be stored in one of these three locations. The argument against storing it in the actual MSR is performance. This is likely to be seldom used while the save/restore is required on every transition. IA32_TSC_ADJUST was created as a way to solve some issues with writing TSC itself so that is not an option either. The remaining option, defined above as our solution has the problem of returning incorrect vmcs tsc_offset values (unless we intercept and fix, not done here) as mentioned above. However, more problematic is that storing the data in vmcs tsc_offset will have a different semantic effect on the system than does using the actual MSR. This is illustrated in the following example: The hypervisor set the IA32_TSC_ADJUST, then the guest sets it and a guest process performs a rdtsc. In this case the guest process will get TSC + IA32_TSC_ADJUST_hyperviser + vmsc tsc_offset including IA32_TSC_ADJUST_guest. While the total system semantics changed the semantics as seen by the guest do not and hence this will not cause a problem. Signed-off-by: NWill Auld <will.auld@intel.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Will Auld 提交于
In order to track who initiated the call (host or guest) to modify an msr value I have changed function call parameters along the call path. The specific change is to add a struct pointer parameter that points to (index, data, caller) information rather than having this information passed as individual parameters. The initial use for this capability is for updating the IA32_TSC_ADJUST msr while setting the tsc value. It is anticipated that this capability is useful for other tasks. Signed-off-by: NWill Auld <will.auld@intel.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 28 11月, 2012 3 次提交
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由 Marcelo Tosatti 提交于
With master clock, a pvclock clock read calculates: ret = system_timestamp + [ (rdtsc + tsc_offset) - tsc_timestamp ] Where 'rdtsc' is the host TSC. system_timestamp and tsc_timestamp are unique, one tuple per VM: the "master clock". Given a host with synchronized TSCs, its obvious that guest TSC must be matched for the above to guarantee monotonicity. Allow master clock usage only if guest TSCs are synchronized. Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Marcelo Tosatti 提交于
KVM added a global variable to guarantee monotonicity in the guest. One of the reasons for that is that the time between 1. ktime_get_ts(×pec); 2. rdtscll(tsc); Is variable. That is, given a host with stable TSC, suppose that two VCPUs read the same time via ktime_get_ts() above. The time required to execute 2. is not the same on those two instances executing in different VCPUS (cache misses, interrupts...). If the TSC value that is used by the host to interpolate when calculating the monotonic time is the same value used to calculate the tsc_timestamp value stored in the pvclock data structure, and a single <system_timestamp, tsc_timestamp> tuple is visible to all vcpus simultaneously, this problem disappears. See comment on top of pvclock_update_vm_gtod_copy for details. Monotonicity is then guaranteed by synchronicity of the host TSCs and guest TSCs. Set TSC stable pvclock flag in that case, allowing the guest to read clock from userspace. Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Marcelo Tosatti 提交于
Allow the caller to pass host tsc value to kvm_x86_ops->read_l1_tsc(). Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 23 9月, 2012 1 次提交
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由 Jan Kiszka 提交于
If we reset a vcpu on INIT, we so far overwrote dr7 as provided by KVM_SET_GUEST_DEBUG, and we also cleared switch_db_regs unconditionally. Fix this by saving the dr7 used for guest debugging and calculating the effective register value as well as switch_db_regs on any potential change. This will change to focus of the set_guest_debug vendor op to update_dp_bp_intercept. Found while trying to stop on start_secondary. Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 21 9月, 2012 1 次提交
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由 Xiao Guangrong 提交于
Exporting KVM exit information to userspace to be consumed by perf. Signed-off-by: NDong Hao <haodong@linux.vnet.ibm.com> [ Dong Hao <haodong@linux.vnet.ibm.com>: rebase it on acme's git tree ] Signed-off-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Acked-by: NMarcelo Tosatti <mtosatti@redhat.com> Cc: Avi Kivity <avi@redhat.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: kvm@vger.kernel.org Cc: Runzhen Wang <runzhen@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1347870675-31495-2-git-send-email-haodong@linux.vnet.ibm.comSigned-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
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- 20 9月, 2012 3 次提交
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由 Gleb Natapov 提交于
Most interrupt are delivered to only one vcpu. Use pre-build tables to find interrupt destination instead of looping through all vcpus. In case of logical mode loop only through vcpus in a logical cluster irq is sent to. Signed-off-by: NGleb Natapov <gleb@redhat.com> Acked-by: NMichael S. Tsirkin <mst@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Avi Kivity 提交于
Instead of branchy code depending on level, gpte.ps, and mmu configuration, prepare everything in a bitmap during mode changes and look it up during runtime. Reviewed-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Avi Kivity 提交于
walk_addr_generic() permission checks are a maze of branchy code, which is performed four times per lookup. It depends on the type of access, efer.nxe, cr0.wp, cr4.smep, and in the near future, cr4.smap. Optimize this away by precalculating all variants and storing them in a bitmap. The bitmap is recalculated when rarely-changing variables change (cr0, cr4) and is indexed by the often-changing variables (page fault error code, pte access permissions). The permission check is moved to the end of the loop, otherwise an SMEP fault could be reported as a false positive, when PDE.U=1 but PTE.U=0. Noted by Xiao Guangrong. The result is short, branch-free code. Reviewed-by: NXiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 06 9月, 2012 1 次提交
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由 Gleb Natapov 提交于
Current code assumes that IO exit was due to instruction emulation and handles execution back to emulator directly. This patch adds new userspace IO exit completion callback that can be set by any other code that caused IO exit to userspace. Signed-off-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 14 8月, 2012 1 次提交
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由 Marcelo Tosatti 提交于
kvm_guest_time_update unconditionally clears hv_clock.flags field, so the notification never reaches the guest. Fix it by allowing PVCLOCK_GUEST_STOPPED to passthrough. Reviewed-by: NEric B Munson <emunson@mgebm.net> Reviewed-by: NAmit Shah <amit.shah@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 06 8月, 2012 1 次提交
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由 Takuya Yoshikawa 提交于
Two reasons: - x86 can integrate rmap and rmap_pde and remove heuristics in __gfn_to_rmap(). - Some architectures do not need rmap. Since rmap is one of the most memory consuming stuff in KVM, ppc'd better restrict the allocation to Book3S HV. Signed-off-by: NTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Acked-by: NPaul Mackerras <paulus@samba.org> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 21 7月, 2012 1 次提交
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由 Michael S. Tsirkin 提交于
When more than 1 source id is in use for the same GSI, we have the following race related to handling irq_states race: CPU 0 clears bit 0. CPU 0 read irq_state as 0. CPU 1 sets level to 1. CPU 1 calls kvm_ioapic_set_irq(1). CPU 0 calls kvm_ioapic_set_irq(0). Now ioapic thinks the level is 0 but irq_state is not 0. Fix by performing all irq_states bitmap handling under pic/ioapic lock. This also removes the need for atomics with irq_states handling. Reported-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NMichael S. Tsirkin <mst@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 19 7月, 2012 2 次提交
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由 Takuya Yoshikawa 提交于
This makes it possible to loop over rmap_pde arrays in the same way as we do over rmap so that we can optimize kvm_handle_hva_range() easily in the following patch. Signed-off-by: NTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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由 Takuya Yoshikawa 提交于
When we tested KVM under memory pressure, with THP enabled on the host, we noticed that MMU notifier took a long time to invalidate huge pages. Since the invalidation was done with mmu_lock held, it not only wasted the CPU but also made the host harder to respond. This patch mitigates this by using kvm_handle_hva_range(). Signed-off-by: NTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Cc: Alexander Graf <agraf@suse.de> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 12 7月, 2012 1 次提交
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由 Mao, Junjie 提交于
This patch handles PCID/INVPCID for guests. Process-context identifiers (PCIDs) are a facility by which a logical processor may cache information for multiple linear-address spaces so that the processor may retain cached information when software switches to a different linear address space. Refer to section 4.10.1 in IA32 Intel Software Developer's Manual Volume 3A for details. For guests with EPT, the PCID feature is enabled and INVPCID behaves as running natively. For guests without EPT, the PCID feature is disabled and INVPCID triggers #UD. Signed-off-by: NJunjie Mao <junjie.mao@intel.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 06 7月, 2012 1 次提交
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由 Robert Richter 提交于
There are macros that are Intel specific and not x86 generic. Rename them into INTEL_*. This patch removes X86_PMC_IDX_GENERIC and does: $ sed -i -e 's/X86_PMC_MAX_/INTEL_PMC_MAX_/g' \ arch/x86/include/asm/kvm_host.h \ arch/x86/include/asm/perf_event.h \ arch/x86/kernel/cpu/perf_event.c \ arch/x86/kernel/cpu/perf_event_p4.c \ arch/x86/kvm/pmu.c $ sed -i -e 's/X86_PMC_IDX_FIXED/INTEL_PMC_IDX_FIXED/g' \ arch/x86/include/asm/perf_event.h \ arch/x86/kernel/cpu/perf_event.c \ arch/x86/kernel/cpu/perf_event_intel.c \ arch/x86/kernel/cpu/perf_event_intel_ds.c \ arch/x86/kvm/pmu.c $ sed -i -e 's/X86_PMC_MSK_/INTEL_PMC_MSK_/g' \ arch/x86/include/asm/perf_event.h \ arch/x86/kernel/cpu/perf_event.c Signed-off-by: NRobert Richter <robert.richter@amd.com> Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1340217996-2254-2-git-send-email-robert.richter@amd.comSigned-off-by: NIngo Molnar <mingo@kernel.org>
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- 25 6月, 2012 1 次提交
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由 Michael S. Tsirkin 提交于
Implementation of PV EOI using shared memory. This reduces the number of exits an interrupt causes as much as by half. The idea is simple: there's a bit, per APIC, in guest memory, that tells the guest that it does not need EOI. We set it before injecting an interrupt and clear before injecting a nested one. Guest tests it using a test and clear operation - this is necessary so that host can detect interrupt nesting - and if set, it can skip the EOI MSR. There's a new MSR to set the address of said register in guest memory. Otherwise not much changed: - Guest EOI is not required - Register is tested & ISR is automatically cleared on exit For testing results see description of previous patch 'kvm_para: guest side for eoi avoidance'. Signed-off-by: NMichael S. Tsirkin <mst@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 17 5月, 2012 1 次提交
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由 Avi Kivity 提交于
Using RCU for lockless shadow walking can increase the amount of memory in use by the system, since RCU grace periods are unpredictable. We also have an unconditional write to a shared variable (reader_counter), which isn't good for scaling. Replace that with a scheme similar to x86's get_user_pages_fast(): disable interrupts during lockless shadow walk to force the freer (kvm_mmu_commit_zap_page()) to wait for the TLB flush IPI to find the processor with interrupts enabled. We also add a new vcpu->mode, READING_SHADOW_PAGE_TABLES, to prevent kvm_flush_remote_tlbs() from avoiding the IPI. Signed-off-by: NAvi Kivity <avi@redhat.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com>
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- 24 4月, 2012 1 次提交
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由 Gleb Natapov 提交于
The patch introduces a bitmap that will hold reasons apic should be checked during vmexit. This is in a preparation for vp eoi patch that will add one more check on vmexit. With the bitmap we can do if(apic_attention) to check everything simultaneously which will add zero overhead on the fast path. Signed-off-by: NGleb Natapov <gleb@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 21 4月, 2012 1 次提交
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由 H. Peter Anvin 提交于
Remove open-coded exception table entries in arch/x86/include/asm/kvm_host.h, and replace them with _ASM_EXTABLE() macros; this will allow us to change the format and type of the exception table entries. Signed-off-by: NH. Peter Anvin <hpa@zytor.com> Cc: David Daney <david.daney@cavium.com> Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Link: http://lkml.kernel.org/r/CA%2B55aFyijf43qSu3N9nWHEBwaGbb7T2Oq9A=9EyR=Jtyqfq_cQ@mail.gmail.com
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- 08 4月, 2012 1 次提交
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由 Takuya Yoshikawa 提交于
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: NTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: NAvi Kivity <avi@redhat.com>
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- 08 3月, 2012 7 次提交
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由 Kevin Wolf 提交于
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: NKevin Wolf <kwolf@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Takuya Yoshikawa 提交于
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: NTakuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Zachary Amsden 提交于
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: NZachary Amsden <zamsden@gmail.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Zachary Amsden 提交于
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: NZachary Amsden <zamsden@gmail.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Marcelo Tosatti 提交于
Redefine the API to take a parameter indicating whether an adjustment is in host or guest cycles. Signed-off-by: NZachary Amsden <zamsden@gmail.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Zachary Amsden 提交于
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: NZachary Amsden <zamsden@gmail.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com> Signed-off-by: NAvi Kivity <avi@redhat.com>
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由 Zachary Amsden 提交于
There are a few improvements that can be made to the TSC offset matching code. First, we don't need to call the 128-bit multiply (especially on a constant number), the code works much nicer to do computation in nanosecond units. Second, the way everything is setup with software TSC rate scaling, we currently have per-cpu rates. Obviously this isn't too desirable to use in practice, but if for some reason we do change the rate of all VCPUs at runtime, then reset the TSCs, we will only want to match offsets for VCPUs running at the same rate. Finally, for the case where we have an unstable host TSC, but rate scaling is being done in hardware, we should call the platform code to compute the TSC offset, so the math is reorganized to recompute the base instead, then transform the base into an offset using the existing API. [avi: fix 64-bit division on i386] Signed-off-by: NZachary Amsden <zamsden@gmail.com> Signed-off-by: NMarcelo Tosatti <mtosatti@redhat.com> KVM: Fix 64-bit division in kvm_write_tsc() Breaks i386 build. Signed-off-by: NAvi Kivity <avi@redhat.com>
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