- 08 Mar, 2012 2 commits
-
-
Zachary Amsden authored
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:
Zachary Amsden <zamsden@gmail.com> Signed-off-by:
Marcelo Tosatti <mtosatti@redhat.com> KVM: Fix 64-bit division in kvm_write_tsc() Breaks i386 build. Signed-off-by:
Avi Kivity <avi@redhat.com>
-
Zachary Amsden authored
This requires some restructuring; rather than use 'virtual_tsc_khz' to indicate whether hardware rate scaling is in effect, we consider each VCPU to always have a virtual TSC rate. Instead, there is new logic above the vendor-specific hardware scaling that decides whether it is even necessary to use and updates all rate variables used by common code. This means we can simply query the virtual rate at any point, which is needed for software rate scaling. There is also now a threshold added to the TSC rate scaling; minor differences and variations of measured TSC rate can accidentally provoke rate scaling to be used when it is not needed. Instead, we have a tolerance variable called tsc_tolerance_ppm, which is the maximum variation from user requested rate at which scaling will be used. The default is 250ppm, which is the half the threshold for NTP adjustment, allowing for some hardware variation. In the event that hardware rate scaling is not available, we can kludge a bit by forcing TSC catchup to turn on when a faster than hardware speed has been requested, but there is nothing available yet for the reverse case; this requires a trap and emulate software implementation for RDTSC, which is still forthcoming. [avi: fix 64-bit division on i386] Signed-off-by:
-
- 05 Mar, 2012 38 commits
-
-
Marcelo Tosatti authored
Increase recommended max vcpus from 64 to 160 (tested internally at Red Hat). Signed-off-by:
-
Igor Mammedov authored
When kvm guest uses kvmclock, it may hang on vcpu hot-plug. This is caused by an overflow in pvclock_get_nsec_offset, u64 delta = tsc - shadow->tsc_timestamp; which in turn is caused by an undefined values from percpu hv_clock that hasn't been initialized yet. Uninitialized clock on being booted cpu is accessed from start_secondary -> smp_callin -> smp_store_cpu_info -> identify_secondary_cpu -> mtrr_ap_init -> mtrr_restore -> stop_machine_from_inactive_cpu -> queue_stop_cpus_work ... -> sched_clock -> kvm_clock_read which is well before x86_cpuinit.setup_percpu_clockev call in start_secondary, where percpu clock is initialized. This patch introduces a hook that allows to setup/initialize per_cpu clock early and avoid overflow due to reading - undefined values - old values if cpu was offlined and then onlined again Another possible early user of this clock source is ftrace that accesses it to get timestamps for ring buffer entries. So if mtrr_ap_init is moved from identify_secondary_cpu to past x86_cpuinit.setup_percpu_clockev in start_secondary, ftrace may cause the same overflow/hang on cpu hot-plug anyway. More complete description of the problem: https://lkml.org/lkml/2012/2/2/101 Credits to Marcelo Tosatti <mtosatti@redhat.com> for hook idea. Acked-by:Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Igor Mammedov <imammedo@redhat.com> Signed-off-by:
-
Gleb Natapov authored
The spec says that during initialization "The edge sense circuit is reset which means that following initialization an interrupt request (IR) input must make a low-to-high transition to generate an interrupt", but currently if edge triggered interrupt is in IRR it is delivered after i8259 initialization. Signed-off-by:
Gleb Natapov <gleb@redhat.com> Signed-off-by:
-
Alexander Graf authored
We're currently allocating 16MB of linear memory on demand when creating a guest. That does work some times, but finding 16MB of linear memory available in the system at runtime is definitely not a given. So let's add another command line option similar to the RMA preallocator, that we can use to keep a pool of page tables around. Now, when a guest gets created it has a pretty low chance of receiving an OOM. Signed-off-by:
Alexander Graf <agraf@suse.de> Signed-off-by:
-
Alexander Graf authored
RMAs and HPT preallocated spaces should be zeroed, so we don't accidently leak information from previous VM executions. Signed-off-by:
Paul Mackerras <paulus@samba.org> Signed-off-by:
-
Alexander Graf authored
We have code to allocate big chunks of linear memory on bootup for later use. This code is currently used for RMA allocation, but can be useful beyond that extent. Make it generic so we can reuse it for other stuff later. Signed-off-by:
-
Alexander Graf authored
When enabling the current KVM code on e500mc, I get the following oops: Oops: Exception in kernel mode, sig: 4 [#1] SMP NR_CPUS=8 P2041 RDB Modules linked in: NIP: c067df4c LR: c067df44 CTR: 00000000 REGS: ee055ed0 TRAP: 0700 Not tainted (3.2.0-10391-g36c5afe) MSR: 00029002 <CE,EE,ME> CR: 24042022 XER: 00000000 TASK = ee0429b0[1] 'swapper/0' THREAD: ee054000 CPU: 2 GPR00: c067df44 ee055f80 ee0429b0 00000000 00000058 0000003f ee211600 60c6b864 GPR08: 7cc903a6 0000002c 00000000 00000001 44042082 2d180088 00000000 00000000 GPR16: c0000a00 00000014 3fffffff 03fe9000 00000015 7ff3be68 c06e0000 00000000 GPR24: 00000000 00000000 00001720 c067df1c c06e0000 00000000 ee054000 c06ab51c NIP [c067df4c] kvmppc_e500_init+0x30/0xf8 LR [c067df44] kvmppc_e500_init+0x28/0xf8 Call Trace: [ee055f80] [c067df44] kvmppc_e500_init+0x28/0xf8 (unreliable) [ee055fb0] [c0001d30] do_one_initcall+0x50/0x1f0 [ee055fe0] [c06721dc] kernel_init+0xa4/0x14c [ee055ff0] [c000e910] kernel_thread+0x4c/0x68 Instruction dump: 9421ffd0 7c0802a6 93410018 9361001c 90010034 93810020 93a10024 93c10028 93e1002c 4bfffe7d 2c030000 408200a4 <7c1082a6> 90010008 7c1182a6 9001000c ---[ end trace b8ef4903fcbf9dd3 ]--- Since it doesn't make sense to run the init function on any non-supported platform, we can just call our "is this platform supported?" function and bail out of init() if it's not. Signed-off-by: -
Paul Mackerras authored
This moves __gfn_to_memslot() and search_memslots() from kvm_main.c to kvm_host.h to reduce the code duplication caused by the need for non-modular code in arch/powerpc/kvm/book3s_hv_rm_mmu.c to call gfn_to_memslot() in real mode. Rather than putting gfn_to_memslot() itself in a header, which would lead to increased code size, this puts __gfn_to_memslot() in a header. Then, the non-modular uses of gfn_to_memslot() are changed to call __gfn_to_memslot() instead. This way there is only one place in the source code that needs to be changed should the gfn_to_memslot() implementation need to be modified. On powerpc, the Book3S HV style of KVM has code that is called from real mode which needs to call gfn_to_memslot() and thus needs this. (Module code is allocated in the vmalloc region, which can't be accessed in real mode.) With this, we can remove builtin_gfn_to_memslot() from book3s_hv_rm_mmu.c. Signed-off-by:
-
Avi Kivity authored
If the guest thinks it's an AMD, it will not have prepared the SYSENTER MSRs, and if the guest executes SYSENTER in compatibility mode, it will fails. Detect this condition and #UD instead, like the spec says. Signed-off-by: -
Julian Stecklina authored
If the guest programs an IPI with level=0 (de-assert) and trig_mode=0 (edge), it is erroneously treated as INIT de-assert and ignored, but to quote the spec: "For this delivery mode [INIT de-assert], the level flag must be set to 0 and trigger mode flag to 1." Signed-off-by:
Julian Stecklina <js@alien8.de> Signed-off-by:
-
Michael S. Tsirkin authored
find_index_from_host_irq returns 0 on error but callers assume < 0 on error. This should not matter much: an out of range irq should never happen since irq handler was registered with this irq #, and even if it does we get a spurious msix irq in guest and typically nothing terrible happens. Still, better to make it consistent. Signed-off-by:
Michael S. Tsirkin <mst@redhat.com> Signed-off-by:
-
Davidlohr Bueso authored
Also use true instead of 1 for enabling by default. Signed-off-by:
Davidlohr Bueso <dave@gnu.org> Signed-off-by:
-
Takuya Yoshikawa authored
Signed-off-by:
Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> Signed-off-by:
-
Takuya Yoshikawa authored
Signed-off-by:
-
Takuya Yoshikawa authored
Signed-off-by:
-
Avi Kivity authored
Currently we treat MOVSX/MOVZX with a byte source as a byte instruction, and change the destination operand size with a hack. Change it to be a word instruction, so the destination receives its natural size, and change the source to be SrcMem8. Signed-off-by:
-
Avi Kivity authored
Useful for MOVSX/MOVZX. Signed-off-by:
-
Scott Wood authored
Instead of keeping separate copies of struct kvm_vcpu_arch_shared (one in the code, one in the docs) that inevitably fail to be kept in sync (already sr[] is missing from the doc version), just point to the header file as the source of documentation on the contents of the magic page. Signed-off-by:
Scott Wood <scottwood@freescale.com> Acked-by:
-
Alexander Graf authored
We need the KVM_REG namespace for generic register settings now, so let's rename the existing users to something different, enabling us to reuse the namespace for more visible interfaces. While at it, also move these private constants to a private header. Signed-off-by:
-
Paul Mackerras authored
This moves the get/set_one_reg implementation down from powerpc.c into booke.c, book3s_pr.c and book3s_hv.c. This avoids #ifdefs in C code, but more importantly, it fixes a bug on Book3s HV where we were accessing beyond the end of the kvm_vcpu struct (via the to_book3s() macro) and corrupting memory, causing random crashes and file corruption. On Book3s HV we only accept setting the HIOR to zero, since the guest runs in supervisor mode and its vectors are never offset from zero. Signed-off-by:
-
Alexander Graf authored
Until now, we always set HIOR based on the PVR, but this is just wrong. Instead, we should be setting HIOR explicitly, so user space can decide what the initial HIOR value is - just like on real hardware. We keep the old PVR based way around for backwards compatibility, but once user space uses the SET_ONE_REG based method, we drop the PVR logic. Signed-off-by:
-
Alexander Graf authored
Right now we transfer a static struct every time we want to get or set registers. Unfortunately, over time we realize that there are more of these than we thought of before and the extensibility and flexibility of transferring a full struct every time is limited. So this is a new approach to the problem. With these new ioctls, we can get and set a single register that is identified by an ID. This allows for very precise and limited transmittal of data. When we later realize that it's a better idea to shove over multiple registers at once, we can reuse most of the infrastructure and simply implement a GET_MANY_REGS / SET_MANY_REGS interface. Signed-off-by:
-
Sasha Levin authored
Currently the code kzalloc()s new VCPUs instead of using the kmem_cache which is created when KVM is initialized. Modify it to allocate VCPUs from that kmem_cache. Signed-off-by:
Sasha Levin <levinsasha928@gmail.com> Acked-by:
-
Liu Yu authored
The existing kvm_stlb_write/kvm_gtlb_write were a poor match for the e500/book3e MMU -- mas1 was passed as "tid", mas2 was limited to "unsigned int" which will be a problem on 64-bit, mas3/7 got split up rather than treated as a single 64-bit word, etc. Signed-off-by:
Liu Yu <yu.liu@freescale.com> [scottwood@freescale.com: made mas2 64-bit, and added mas8 init] Signed-off-by:
-
Paul Mackerras authored
This changes the implementation of kvm_vm_ioctl_get_dirty_log() for Book3s HV guests to use the hardware C (changed) bits in the guest hashed page table. Since this makes the implementation quite different from the Book3s PR case, this moves the existing implementation from book3s.c to book3s_pr.c and creates a new implementation in book3s_hv.c. That implementation calls kvmppc_hv_get_dirty_log() to do the actual work by calling kvm_test_clear_dirty on each page. It iterates over the HPTEs, clearing the C bit if set, and returns 1 if any C bit was set (including the saved C bit in the rmap entry). Signed-off-by:
-
Paul Mackerras authored
This uses the host view of the hardware R (referenced) bit to speed up kvm_age_hva() and kvm_test_age_hva(). Instead of removing all the relevant HPTEs in kvm_age_hva(), we now just reset their R bits if set. Also, kvm_test_age_hva() now scans the relevant HPTEs to see if any of them have R set. Signed-off-by:
-
Paul Mackerras authored
This allows both the guest and the host to use the referenced (R) and changed (C) bits in the guest hashed page table. The guest has a view of R and C that is maintained in the guest_rpte field of the revmap entry for the HPTE, and the host has a view that is maintained in the rmap entry for the associated gfn. Both view are updated from the guest HPT. If a bit (R or C) is zero in either view, it will be initially set to zero in the HPTE (or HPTEs), until set to 1 by hardware. When an HPTE is removed for any reason, the R and C bits from the HPTE are ORed into both views. We have to be careful to read the R and C bits from the HPTE after invalidating it, but before unlocking it, in case of any late updates by the hardware. Signed-off-by:
-
Paul Mackerras authored
This reworks the implementations of the H_REMOVE and H_BULK_REMOVE hcalls to make sure that we keep the HPTE locked and in the reverse- mapping chain until we have finished invalidating it. Previously we would remove it from the chain and unlock it before invalidating it, leaving a tiny window when the guest could access the page even though we believe we have removed it from the guest (e.g., kvm_unmap_hva() has been called for the page and has found no HPTEs in the chain). In addition, we'll need this for future patches where we will need to read the R and C bits in the HPTE after invalidating it. Doing this required restructuring kvmppc_h_bulk_remove() substantially. Since we want to batch up the tlbies, we now need to keep several HPTEs locked simultaneously. In order to avoid possible deadlocks, we don't spin on the HPTE bitlock for any except the first HPTE in a batch. If we can't acquire the HPTE bitlock for the second or subsequent HPTE, we terminate the batch at that point, do the tlbies that we have accumulated so far, unlock those HPTEs, and then start a new batch to do the remaining invalidations. Signed-off-by:
-
Matt Evans authored
PPC KVM lacks these two capabilities, and as such a userland system must assume a max of 4 VCPUs (following api.txt). With these, a userland can determine a more realistic limit. Signed-off-by:
Matt Evans <matt@ozlabs.org> Signed-off-by:
-
Matt Evans authored
Fix usage of vcpu struct before check that it's actually valid. Signed-off-by:
-
Paul Mackerras authored
With this, if a guest does an H_ENTER with a read/write HPTE on a page which is currently read-only, we make the actual HPTE inserted be a read-only version of the HPTE. We now intercept protection faults as well as HPTE not found faults, and for a protection fault we work out whether it should be reflected to the guest (e.g. because the guest HPTE didn't allow write access to usermode) or handled by switching to kernel context and calling kvmppc_book3s_hv_page_fault, which will then request write access to the page and update the actual HPTE. Signed-off-by:
-
Paul Mackerras authored
This adds an smp_wmb in kvm_mmu_notifier_invalidate_range_end() and an smp_rmb in mmu_notifier_retry() so that mmu_notifier_retry() will give the correct answer when called without kvm->mmu_lock being held. PowerPC Book3S HV KVM wants to use a bitlock per guest page rather than a single global spinlock in order to improve the scalability of updates to the guest MMU hashed page table, and so needs this. Signed-off-by:
-
Paul Mackerras authored
This adds the infrastructure to enable us to page out pages underneath a Book3S HV guest, on processors that support virtualized partition memory, that is, POWER7. Instead of pinning all the guest's pages, we now look in the host userspace Linux page tables to find the mapping for a given guest page. Then, if the userspace Linux PTE gets invalidated, kvm_unmap_hva() gets called for that address, and we replace all the guest HPTEs that refer to that page with absent HPTEs, i.e. ones with the valid bit clear and the HPTE_V_ABSENT bit set, which will cause an HDSI when the guest tries to access them. Finally, the page fault handler is extended to reinstantiate the guest HPTE when the guest tries to access a page which has been paged out. Since we can't intercept the guest DSI and ISI interrupts on PPC970, we still have to pin all the guest pages on PPC970. We have a new flag, kvm->arch.using_mmu_notifiers, that indicates whether we can page guest pages out. If it is not set, the MMU notifier callbacks do nothing and everything operates as before. Signed-off-by:
-
Paul Mackerras authored
This provides the low-level support for MMIO emulation in Book3S HV guests. When the guest tries to map a page which is not covered by any memslot, that page is taken to be an MMIO emulation page. Instead of inserting a valid HPTE, we insert an HPTE that has the valid bit clear but another hypervisor software-use bit set, which we call HPTE_V_ABSENT, to indicate that this is an absent page. An absent page is treated much like a valid page as far as guest hcalls (H_ENTER, H_REMOVE, H_READ etc.) are concerned, except of course that an absent HPTE doesn't need to be invalidated with tlbie since it was never valid as far as the hardware is concerned. When the guest accesses a page for which there is an absent HPTE, it will take a hypervisor data storage interrupt (HDSI) since we now set the VPM1 bit in the LPCR. Our HDSI handler for HPTE-not-present faults looks up the hash table and if it finds an absent HPTE mapping the requested virtual address, will switch to kernel mode and handle the fault in kvmppc_book3s_hv_page_fault(), which at present just calls kvmppc_hv_emulate_mmio() to set up the MMIO emulation. This is based on an earlier patch by Benjamin Herrenschmidt, but since heavily reworked. Signed-off-by:
-
Paul Mackerras authored
This expands the reverse mapping array to contain two links for each HPTE which are used to link together HPTEs that correspond to the same guest logical page. Each circular list of HPTEs is pointed to by the rmap array entry for the guest logical page, pointed to by the relevant memslot. Links are 32-bit HPT entry indexes rather than full 64-bit pointers, to save space. We use 3 of the remaining 32 bits in the rmap array entries as a lock bit, a referenced bit and a present bit (the present bit is needed since HPTE index 0 is valid). The bit lock for the rmap chain nests inside the HPTE lock bit. Signed-off-by:
-
Paul Mackerras authored
This provides for the case where userspace maps an I/O device into the address range of a memory slot using a VM_PFNMAP mapping. In that case, we work out the pfn from vma->vm_pgoff, and record the cache enable bits from vma->vm_page_prot in two low-order bits in the slot_phys array entries. Then, in kvmppc_h_enter() we check that the cache bits in the HPTE that the guest wants to insert match the cache bits in the slot_phys array entry. However, we do allow the guest to create what it thinks is a non-cacheable or write-through mapping to memory that is actually cacheable, so that we can use normal system memory as part of an emulated device later on. In that case the actual HPTE we insert is a cacheable HPTE. Signed-off-by:
-
Paul Mackerras authored
This relaxes the requirement that the guest memory be provided as 16MB huge pages, allowing it to be provided as normal memory, i.e. in pages of PAGE_SIZE bytes (4k or 64k). To allow this, we index the kvm->arch.slot_phys[] arrays with a small page index, even if huge pages are being used, and use the low-order 5 bits of each entry to store the order of the enclosing page with respect to normal pages, i.e. log_2(enclosing_page_size / PAGE_SIZE). Signed-off-by:
-
Paul Mackerras authored
This removes the code from kvmppc_core_prepare_memory_region() that looked up the VMA for the region being added and called hva_to_page to get the pfns for the memory. We have no guarantee that there will be anything mapped there at the time of the KVM_SET_USER_MEMORY_REGION ioctl call; userspace can do that ioctl and then map memory into the region later. Instead we defer looking up the pfn for each memory page until it is needed, which generally means when the guest does an H_ENTER hcall on the page. Since we can't call get_user_pages in real mode, if we don't already have the pfn for the page, kvmppc_h_enter() will return H_TOO_HARD and we then call kvmppc_virtmode_h_enter() once we get back to kernel context. That calls kvmppc_get_guest_page() to get the pfn for the page, and then calls back to kvmppc_h_enter() to redo the HPTE insertion. When the first vcpu starts executing, we need to have the RMO or VRMA region mapped so that the guest's real mode accesses will work. Thus we now have a check in kvmppc_vcpu_run() to see if the RMO/VRMA is set up and if not, call kvmppc_hv_setup_rma(). It checks if the memslot starting at guest physical 0 now has RMO memory mapped there; if so it sets it up for the guest, otherwise on POWER7 it sets up the VRMA. The function that does that, kvmppc_map_vrma, is now a bit simpler, as it calls kvmppc_virtmode_h_enter instead of creating the HPTE itself. Since we are now potentially updating entries in the slot_phys[] arrays from multiple vcpu threads, we now have a spinlock protecting those updates to ensure that we don't lose track of any references to pages. Signed-off-by:
-
