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2016-01-15kvm: rename pfn_t to kvm_pfn_tDan Williams
To date, we have implemented two I/O usage models for persistent memory, PMEM (a persistent "ram disk") and DAX (mmap persistent memory into userspace). This series adds a third, DAX-GUP, that allows DAX mappings to be the target of direct-i/o. It allows userspace to coordinate DMA/RDMA from/to persistent memory. The implementation leverages the ZONE_DEVICE mm-zone that went into 4.3-rc1 (also discussed at kernel summit) to flag pages that are owned and dynamically mapped by a device driver. The pmem driver, after mapping a persistent memory range into the system memmap via devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus page-backed pmem-pfns via flags in the new pfn_t type. The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the resulting pte(s) inserted into the process page tables with a new _PAGE_DEVMAP flag. Later, when get_user_pages() is walking ptes it keys off _PAGE_DEVMAP to pin the device hosting the page range active. Finally, get_page() and put_page() are modified to take references against the device driver established page mapping. Finally, this need for "struct page" for persistent memory requires memory capacity to store the memmap array. Given the memmap array for a large pool of persistent may exhaust available DRAM introduce a mechanism to allocate the memmap from persistent memory. The new "struct vmem_altmap *" parameter to devm_memremap_pages() enables arch_add_memory() to use reserved pmem capacity rather than the page allocator. This patch (of 18): The core has developed a need for a "pfn_t" type [1]. Move the existing pfn_t in KVM to kvm_pfn_t [2]. [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html [2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.html Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-12Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "PPC changes will come next week. - s390: Support for runtime instrumentation within guests, support of 248 VCPUs. - ARM: rewrite of the arm64 world switch in C, support for 16-bit VM identifiers. Performance counter virtualization missed the boat. - x86: Support for more Hyper-V features (synthetic interrupt controller), MMU cleanups" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (115 commits) kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL kvm/x86: Hyper-V SynIC timers tracepoints kvm/x86: Hyper-V SynIC tracepoints kvm/x86: Update SynIC timers on guest entry only kvm/x86: Skip SynIC vector check for QEMU side kvm/x86: Hyper-V fix SynIC timer disabling condition kvm/x86: Reorg stimer_expiration() to better control timer restart kvm/x86: Hyper-V unify stimer_start() and stimer_restart() kvm/x86: Drop stimer_stop() function kvm/x86: Hyper-V timers fix incorrect logical operation KVM: move architecture-dependent requests to arch/ KVM: renumber vcpu->request bits KVM: document which architecture uses each request bit KVM: Remove unused KVM_REQ_KICK to save a bit in vcpu->requests kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clock KVM: s390: implement the RI support of guest kvm/s390: drop unpaired smp_mb kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpa KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table() arm/arm64: KVM: Detect vGIC presence at runtime ...
2016-01-12kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROLHuaitong Han
vmx_cpuid_tries to update SECONDARY_VM_EXEC_CONTROL in the VMCS, but it will cause a vmwrite error on older CPUs because the code does not check for the presence of CPU_BASED_ACTIVATE_SECONDARY_CONTROLS. This will get rid of the following trace on e.g. Core2 6600: vmwrite error: reg 401e value 10 (err 12) Call Trace: [<ffffffff8116e2b9>] dump_stack+0x40/0x57 [<ffffffffa020b88d>] vmx_cpuid_update+0x5d/0x150 [kvm_intel] [<ffffffffa01d8fdc>] kvm_vcpu_ioctl_set_cpuid2+0x4c/0x70 [kvm] [<ffffffffa01b8363>] kvm_arch_vcpu_ioctl+0x903/0xfa0 [kvm] Fixes: feda805fe7c4ed9cf78158e73b1218752e3b4314 Cc: stable@vger.kernel.org Reported-by: Zdenek Kaspar <zkaspar82@gmail.com> Signed-off-by: Huaitong Han <huaitong.han@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-11Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu updates from Ingo Molnar: "The main changes in this cycle were: - Improved CPU ID handling code and related enhancements (Borislav Petkov) - RDRAND fix (Len Brown)" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Replace RDRAND forced-reseed with simple sanity check x86/MSR: Chop off lower 32-bit value x86/cpu: Fix MSR value truncation issue x86/cpu/amd, kvm: Satisfy guest kernel reads of IC_CFG MSR kvm: Add accessors for guest CPU's family, model, stepping x86/cpu: Unify CPU family, model, stepping calculation
2016-01-08kvm/x86: Hyper-V SynIC timers tracepointsAndrey Smetanin
Trace the following Hyper SynIC timers events: * periodic timer start * one-shot timer start * timer callback * timer expiration and message delivery result * timer config setup * timer count setup * timer cleanup Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Hyper-V SynIC tracepointsAndrey Smetanin
Trace the following Hyper SynIC events: * set msr * set sint irq * ack sint * sint irq eoi Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Update SynIC timers on guest entry onlyAndrey Smetanin
Consolidate updating the Hyper-V SynIC timers in a single place: on guest entry in processing KVM_REQ_HV_STIMER request. This simplifies the overall logic, and makes sure the most current state of msrs and guest clock is used for arming the timers (to achieve that, KVM_REQ_HV_STIMER has to be processed after KVM_REQ_CLOCK_UPDATE). Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Skip SynIC vector check for QEMU sideAndrey Smetanin
QEMU zero-inits Hyper-V SynIC vectors. We should allow that, and don't reject zero values if set by the host. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Hyper-V fix SynIC timer disabling conditionAndrey Smetanin
Hypervisor Function Specification(HFS) doesn't require to disable SynIC timer at timer config write if timer->count = 0. So drop this check, this allow to load timers MSR's during migration restore, because config are set before count in QEMU side. Also fix condition according to HFS doc(15.3.1): "It is not permitted to set the SINTx field to zero for an enabled timer. If attempted, the timer will be marked disabled (that is, bit 0 cleared) immediately." Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Reorg stimer_expiration() to better control timer restartAndrey Smetanin
Split stimer_expiration() into two parts - timer expiration message sending and timer restart/cleanup based on timer state(config). This also fixes a bug where a one-shot timer message whose delivery failed once would get lost for good. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Hyper-V unify stimer_start() and stimer_restart()Andrey Smetanin
This will be used in future to start Hyper-V SynIC timer in several places by one logic in one function. Changes v2: * drop stimer->count == 0 check inside stimer_start() * comment stimer_start() assumptions Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Drop stimer_stop() functionAndrey Smetanin
The function stimer_stop() is called in one place so remove the function and replace it's call by function content. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08kvm/x86: Hyper-V timers fix incorrect logical operationAndrey Smetanin
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-08KVM: move architecture-dependent requests to arch/Paolo Bonzini
Since the numbers now overlap, it makes sense to enumerate them in asm/kvm_host.h rather than linux/kvm_host.h. Functions that refer to architecture-specific requests are also moved to arch/. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-07kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clockNicholas Krause
This makes sure the wall clock is updated only after an odd version value is successfully written to guest memory. Signed-off-by: Nicholas Krause <xerofoify@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-07kvm: x86: only channel 0 of the i8254 is linked to the HPETPaolo Bonzini
While setting the KVM PIT counters in 'kvm_pit_load_count', if 'hpet_legacy_start' is set, the function disables the timer on channel[0], instead of the respective index 'channel'. This is because channels 1-3 are not linked to the HPET. Fix the caller to only activate the special HPET processing for channel 0. Reported-by: P J P <pjp@fedoraproject.org> Fixes: 0185604c2d82c560dab2f2933a18f797e74ab5a8 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-01-07kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpaDavid Matlack
The comment had the meaning of mmu.gva_to_gpa and nested_mmu.gva_to_gpa swapped. Fix that, and also add some details describing how each translation works. Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22KVM: x86: Reload pit counters for all channels when restoring stateAndrew Honig
Currently if userspace restores the pit counters with a count of 0 on channels 1 or 2 and the guest attempts to read the count on those channels, then KVM will perform a mod of 0 and crash. This will ensure that 0 values are converted to 65536 as per the spec. This is CVE-2015-7513. Signed-off-by: Andy Honig <ahonig@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22KVM: MTRR: treat memory as writeback if MTRR is disabled in guest CPUIDPaolo Bonzini
Virtual machines can be run with CPUID such that there are no MTRRs. In that case, the firmware will never enable MTRRs and it is obviously undesirable to run the guest entirely with UC memory. Check out guest CPUID, and use WB memory if MTRR do not exist. Cc: qemu-stable@nongnu.org Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22KVM: MTRR: observe maxphyaddr from guest CPUID, not hostPaolo Bonzini
Conversion of MTRRs to ranges used the maxphyaddr from the boot CPU. This is wrong, because var_mtrr_range's mask variable then is discontiguous (like FF00FFFF000, where the first run of 0s corresponds to the bits between host and guest maxphyaddr). Instead always set up the masks to be full 64-bit values---we know that the reserved bits at the top are zero, and we can restore them when reading the MSR. This way var_mtrr_range gets a mask that just works. Fixes: a13842dc668b40daef4327294a6d3bdc8bd30276 Cc: qemu-stable@nongnu.org Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561 Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-22KVM: MTRR: fix fixed MTRR segment look upAlexis Dambricourt
This fixes the slow-down of VM running with pci-passthrough, since some MTRR range changed from MTRR_TYPE_WRBACK to MTRR_TYPE_UNCACHABLE. Memory in the 0K-640K range was incorrectly treated as uncacheable. Fixes: f7bfb57b3e89ff89c0da9f93dedab89f68d6ca27 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=107561 Cc: qemu-stable@nongnu.org Signed-off-by: Alexis Dambricourt <alexis.dambricourt@gmail.com> [Use correct BZ for "Fixes" annotation. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-18KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table()Takuya Yoshikawa
Not just in order to clean up the code, but to make it faster by using enhanced instructions: the initialization became 20-30% faster on our testing machine. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16kvm/x86: Remove Hyper-V SynIC timer stoppingAndrey Smetanin
It's possible that guest send us Hyper-V EOM at the middle of Hyper-V SynIC timer running, so we start processing of Hyper-V SynIC timers in vcpu context and stop the Hyper-V SynIC timer unconditionally: host guest ------------------------------------------------------------------------------ start periodic stimer start periodic timer timer expires after 15ms send expiration message into guest restart periodic timer timer expires again after 15 ms msg slot is still not cleared so setup ->msg_pending (1) restart periodic timer process timer msg and clear slot ->msg_pending was set: send EOM into host received EOM kvm_make_request(KVM_REQ_HV_STIMER) kvm_hv_process_stimers(): ... stimer_stop() if (time_now >= stimer->exp_time) stimer_expiration(stimer); Because the timer was rearmed at (1), time_now < stimer->exp_time and stimer_expiration is not called. The timer then never fires. The patch fixes such situation by not stopping Hyper-V SynIC timer at all, because it's safe to restart it without stop in vcpu context and timer callback always returns HRTIMER_NORESTART. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16KVM: vmx: detect mismatched size in VMCS read/writePaolo Bonzini
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- I am sending this as RFC because the error messages it produces are very ugly. Because of inlining, the original line is lost. The alternative is to change vmcs_read/write/checkXX into macros, but then you need to have a single huge BUILD_BUG_ON or BUILD_BUG_ON_MSG because multiple BUILD_BUG_ON* with the same __LINE__ are not supported well.
2015-12-16KVM: VMX: fix read/write sizes of VMCS fields in dump_vmcsPaolo Bonzini
This was not printing the high parts of several 64-bit fields on 32-bit kernels. Separate from the previous one to make the patches easier to review. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16KVM: VMX: fix read/write sizes of VMCS fieldsPaolo Bonzini
In theory this should have broken EPT on 32-bit kernels (due to reading the high part of natural-width field GUEST_CR3). Not sure if no one noticed or the processor behaves differently from the documentation. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16KVM: VMX: fix the writing POSTED_INTR_NVLi RongQing
POSTED_INTR_NV is 16bit, should not use 64bit write function [ 5311.676074] vmwrite error: reg 3 value 0 (err 12) [ 5311.680001] CPU: 49 PID: 4240 Comm: qemu-system-i38 Tainted: G I 4.1.13-WR8.0.0.0_standard #1 [ 5311.689343] Hardware name: Intel Corporation S2600WT2/S2600WT2, BIOS SE5C610.86B.01.01.0008.021120151325 02/11/2015 [ 5311.699550] 00000000 00000000 e69a7e1c c1950de1 00000000 e69a7e38 fafcff45 fafebd24 [ 5311.706924] 00000003 00000000 0000000c b6a06dfa e69a7e40 fafcff79 e69a7eb0 fafd5f57 [ 5311.714296] e69a7ec0 c1080600 00000000 00000001 c0e18018 000001be 00000000 00000b43 [ 5311.721651] Call Trace: [ 5311.722942] [<c1950de1>] dump_stack+0x4b/0x75 [ 5311.726467] [<fafcff45>] vmwrite_error+0x35/0x40 [kvm_intel] [ 5311.731444] [<fafcff79>] vmcs_writel+0x29/0x30 [kvm_intel] [ 5311.736228] [<fafd5f57>] vmx_create_vcpu+0x337/0xb90 [kvm_intel] [ 5311.741600] [<c1080600>] ? dequeue_task_fair+0x2e0/0xf60 [ 5311.746197] [<faf3b9ca>] kvm_arch_vcpu_create+0x3a/0x70 [kvm] [ 5311.751278] [<faf29e9d>] kvm_vm_ioctl+0x14d/0x640 [kvm] [ 5311.755771] [<c1129d44>] ? free_pages_prepare+0x1a4/0x2d0 [ 5311.760455] [<c13e2842>] ? debug_smp_processor_id+0x12/0x20 [ 5311.765333] [<c10793be>] ? sched_move_task+0xbe/0x170 [ 5311.769621] [<c11752b3>] ? kmem_cache_free+0x213/0x230 [ 5311.774016] [<faf29d50>] ? kvm_set_memory_region+0x60/0x60 [kvm] [ 5311.779379] [<c1199fa2>] do_vfs_ioctl+0x2e2/0x500 [ 5311.783285] [<c11752b3>] ? kmem_cache_free+0x213/0x230 [ 5311.787677] [<c104dc73>] ? __mmdrop+0x63/0xd0 [ 5311.791196] [<c104dc73>] ? __mmdrop+0x63/0xd0 [ 5311.794712] [<c104dc73>] ? __mmdrop+0x63/0xd0 [ 5311.798234] [<c11a2ed7>] ? __fget+0x57/0x90 [ 5311.801559] [<c11a2f72>] ? __fget_light+0x22/0x50 [ 5311.805464] [<c119a240>] SyS_ioctl+0x80/0x90 [ 5311.808885] [<c1957d30>] sysenter_do_call+0x12/0x12 [ 5312.059280] kvm: zapping shadow pages for mmio generation wraparound [ 5313.678415] kvm [4231]: vcpu0 disabled perfctr wrmsr: 0xc2 data 0xffff [ 5313.726518] kvm [4231]: vcpu0 unhandled rdmsr: 0x570 Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Cc: Yang Zhang <yang.z.zhang@Intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16kvm/x86: Hyper-V SynIC timersAndrey Smetanin
Per Hyper-V specification (and as required by Hyper-V-aware guests), SynIC provides 4 per-vCPU timers. Each timer is programmed via a pair of MSRs, and signals expiration by delivering a special format message to the configured SynIC message slot and triggering the corresponding synthetic interrupt. Note: as implemented by this patch, all periodic timers are "lazy" (i.e. if the vCPU wasn't scheduled for more than the timer period the timer events are lost), regardless of the corresponding configuration MSR. If deemed necessary, the "catch up" mode (the timer period is shortened until the timer catches up) will be implemented later. Changes v2: * Use remainder to calculate periodic timer expiration time Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Vitaly Kuznetsov <vkuznets@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16kvm/x86: Hyper-V SynIC message slot pending clearing at SINT ackAndrey Smetanin
The SynIC message protocol mandates that the message slot is claimed by atomically setting message type to something other than HVMSG_NONE. If another message is to be delivered while the slot is still busy, message pending flag is asserted to indicate to the guest that the hypervisor wants to be notified when the slot is released. To make sure the protocol works regardless of where the message sources are (kernel or userspace), clear the pending flag on SINT ACK notification, and let the message sources compete for the slot again. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Vitaly Kuznetsov <vkuznets@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16kvm/x86: Hyper-V internal helper to read MSR HV_X64_MSR_TIME_REF_COUNTAndrey Smetanin
This helper will be used also in Hyper-V SynIC timers implementation. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Vitaly Kuznetsov <vkuznets@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16kvm/x86: Added Hyper-V vcpu_to_hv_vcpu()/hv_vcpu_to_vcpu() helpersAndrey Smetanin
Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Vitaly Kuznetsov <vkuznets@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-16kvm/x86: Rearrange func's declarations inside Hyper-V headerAndrey Smetanin
This rearrangement places functions declarations together according to their functionality, so future additions will be simplier. Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: "K. Y. Srinivasan" <kys@microsoft.com> CC: Haiyang Zhang <haiyangz@microsoft.com> CC: Vitaly Kuznetsov <vkuznets@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-14KVM: VMX: Fix host initiated access to guest MSR_TSC_AUXHaozhong Zhang
The current handling of accesses to guest MSR_TSC_AUX returns error if vcpu does not support rdtscp, though those accesses are initiated by host. This can result in the reboot failure of some versions of QEMU. This patch fixes this issue by passing those host initiated accesses for further handling instead. Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-11kvm: x86: move tracepoints outside extended quiescent statePaolo Bonzini
Invoking tracepoints within kvm_guest_enter/kvm_guest_exit causes a lockdep splat. Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-26KVM: x86: MMU: Remove unused parameter parent_pte from kvm_mmu_get_page()Takuya Yoshikawa
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-26KVM: x86: MMU: Use for_each_rmap_spte macro instead of pte_list_walk()Takuya Yoshikawa
As kvm_mmu_get_page() was changed so that every parent pointer would not get into the sp->parent_ptes chain before the entry pointed to by it was set properly, we can use the for_each_rmap_spte macro instead of pte_list_walk(). Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-26KVM: x86: MMU: Move parent_pte handling from kvm_mmu_get_page() to ↵Takuya Yoshikawa
link_shadow_page() Every time kvm_mmu_get_page() is called with a non-NULL parent_pte argument, link_shadow_page() follows that to set the parent entry so that the new mapping will point to the returned page table. Moving parent_pte handling there allows to clean up the code because parent_pte is passed to kvm_mmu_get_page() just for mark_unsync() and mmu_page_add_parent_pte(). In addition, the patch avoids calling mark_unsync() for other parents in the sp->parent_ptes chain than the newly added parent_pte, because they have been there since before the current page fault handling started. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Move initialization of parent_ptes out from kvm_mmu_alloc_page()Takuya Yoshikawa
Make kvm_mmu_alloc_page() do just what its name tells to do, and remove the extra allocation error check and zero-initialization of parent_ptes: shadow page headers allocated by kmem_cache_zalloc() are always in the per-VCPU pools. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Consolidate BUG_ON checks for reverse-mapped sptesTakuya Yoshikawa
At some call sites of rmap_get_first() and rmap_get_next(), BUG_ON is placed right after the call to detect unrelated sptes which must not be found in the reverse-mapping list. Move this check in rmap_get_first/next() so that all call sites, not just the users of the for_each_rmap_spte() macro, will be checked the same way. One thing to keep in mind is that kvm_mmu_unlink_parents() also uses rmap_get_first() to handle parent sptes. The change will not break it because parent sptes are present, at least until drop_parent_pte() actually unlinks them, and not mmio-sptes. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Remove is_rmap_spte() and use is_shadow_present_pte()Takuya Yoshikawa
is_rmap_spte(), originally named is_rmap_pte(), was introduced when the simple reverse mapping was implemented by commit cd4a4e5374110444 ("[PATCH] KVM: MMU: Implement simple reverse mapping"). At that point, its role was clear and only rmap_add() and rmap_remove() were using it to select sptes that need to be reverse-mapped. Independently of that, is_shadow_present_pte() was first introduced by commit c7addb902054195b ("KVM: Allow not-present guest page faults to bypass kvm") to do bypass_guest_pf optimization, which does not exist any more. These two seem to have changed their roles somewhat, and is_rmap_spte() just calls is_shadow_present_pte() now. Since using both of them without clear distinction just makes the code confusing, remove is_rmap_spte(). Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Make mmu_set_spte() return emulate valueTakuya Yoshikawa
mmu_set_spte()'s code is based on the assumption that the emulate parameter has a valid pointer value if set_spte() returns true and write_fault is not zero. In other cases, emulate may be NULL, so a NULL-check is needed. Stop passing emulate pointer and make mmu_set_spte() return the emulate value instead to clean up this complex interface. Prefetch functions can just throw away the return value. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Add helper function to clear a bit in unsync child bitmapTakuya Yoshikawa
Both __mmu_unsync_walk() and mmu_pages_clear_parents() have three line code which clears a bit in the unsync child bitmap; the former places it inside a loop block and uses a few goto statements to jump to it. A new helper function, clear_unsync_child_bit(), makes the code cleaner. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Remove unused parameter of __direct_map()Takuya Yoshikawa
Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: Encapsulate the type of rmap-chain head in a new structTakuya Yoshikawa
New struct kvm_rmap_head makes the code type-safe to some extent. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: MMU: always set accessed bit in shadow PTEsPaolo Bonzini
Commit 7a1638ce4220 ("nEPT: Redefine EPT-specific link_shadow_page()", 2013-08-05) says: Since nEPT doesn't support A/D bit, we should not set those bit when building the shadow page table. but this is not necessary. Even though nEPT doesn't support A/D bits, and hence the vmcs12 EPT pointer will never enable them, we always use them for shadow page tables if available (see construct_eptp in vmx.c). So we can set the A/D bits freely in the shadow page table. This patch hence basically reverts commit 7a1638ce4220. Cc: Yang Zhang <yang.z.zhang@Intel.com> Cc: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: correctly print #AC in tracesPaolo Bonzini
Poor #AC was so unimportant until a few days ago that we were not even tracing its name correctly. But now it's all over the place. Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: svm: add support for RDTSCPPaolo Bonzini
RDTSCP was never supported for AMD CPUs, which nobody noticed because Linux does not use it. But exactly the fact that Linux does not use it makes the implementation very simple; we can freely trash MSR_TSC_AUX while running the guest. Cc: Joerg Roedel <joro@8bytes.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25KVM: x86: expose MSR_TSC_AUX to userspacePaolo Bonzini
If we do not do this, it is not properly saved and restored across migration. Windows notices due to its self-protection mechanisms, and is very upset about it (blue screen of death). Cc: Radim Krcmar <rkrcmar@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25kvm/x86: Hyper-V kvm exitAndrey Smetanin
A new vcpu exit is introduced to notify the userspace of the changes in Hyper-V SynIC configuration triggered by guest writing to the corresponding MSRs. Changes v4: * exit into userspace only if guest writes into SynIC MSR's Changes v3: * added KVM_EXIT_HYPERV types and structs notes into docs Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25kvm/x86: Hyper-V synthetic interrupt controllerAndrey Smetanin
SynIC (synthetic interrupt controller) is a lapic extension, which is controlled via MSRs and maintains for each vCPU - 16 synthetic interrupt "lines" (SINT's); each can be configured to trigger a specific interrupt vector optionally with auto-EOI semantics - a message page in the guest memory with 16 256-byte per-SINT message slots - an event flag page in the guest memory with 16 2048-bit per-SINT event flag areas The host triggers a SINT whenever it delivers a new message to the corresponding slot or flips an event flag bit in the corresponding area. The guest informs the host that it can try delivering a message by explicitly asserting EOI in lapic or writing to End-Of-Message (EOM) MSR. The userspace (qemu) triggers interrupts and receives EOM notifications via irqfd with resampler; for that, a GSI is allocated for each configured SINT, and irq_routing api is extended to support GSI-SINT mapping. Changes v4: * added activation of SynIC by vcpu KVM_ENABLE_CAP * added per SynIC active flag * added deactivation of APICv upon SynIC activation Changes v3: * added KVM_CAP_HYPERV_SYNIC and KVM_IRQ_ROUTING_HV_SINT notes into docs Changes v2: * do not use posted interrupts for Hyper-V SynIC AutoEOI vectors * add Hyper-V SynIC vectors into EOI exit bitmap * Hyper-V SyniIC SINT msr write logic simplified Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com> Reviewed-by: Roman Kagan <rkagan@virtuozzo.com> Signed-off-by: Denis V. Lunev <den@openvz.org> CC: Gleb Natapov <gleb@kernel.org> CC: Paolo Bonzini <pbonzini@redhat.com> CC: Roman Kagan <rkagan@virtuozzo.com> CC: Denis V. Lunev <den@openvz.org> CC: qemu-devel@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>