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* KVM: PPC: Move and undef TRACE_INCLUDE_PATH/FILEScott Wood2018-11-074-8/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | TRACE_INCLUDE_PATH and TRACE_INCLUDE_FILE are used by <trace/define_trace.h>, so like that #include, they should be outside #ifdef protection. They also need to be #undefed before defining, in case multiple trace headers are included by the same C file. This became the case on book3e after commit cf4a6085151a ("powerpc/mm: Add missing tracepoint for tlbie"), leading to the following build error: CC arch/powerpc/kvm/powerpc.o In file included from arch/powerpc/kvm/powerpc.c:51:0: arch/powerpc/kvm/trace.h:9:0: error: "TRACE_INCLUDE_PATH" redefined [-Werror] #define TRACE_INCLUDE_PATH . ^ In file included from arch/powerpc/kvm/../mm/mmu_decl.h:25:0, from arch/powerpc/kvm/powerpc.c:48: ./arch/powerpc/include/asm/trace.h:224:0: note: this is the location of the previous definition #define TRACE_INCLUDE_PATH asm ^ cc1: all warnings being treated as errors Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de> Signed-off-by: Scott Wood <oss@buserror.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* Merge tag 'powerpc-4.20-2' of ↵Linus Torvalds2018-11-022-6/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: "Some things that I missed due to travel, or that came in late. Two fixes also going to stable: - A revert of a buggy change to the 8xx TLB miss handlers. - Our flushing of SPE (Signal Processing Engine) registers on fork was broken. Other changes: - A change to the KVM decrementer emulation to use proper APIs. - Some cleanups to the way we do code patching in the 8xx code. - Expose the maximum possible memory for the system in /proc/powerpc/lparcfg. - Merge some updates from Scott: "a couple device tree updates, and a fix for a missing prototype warning" A few other minor fixes and a handful of fixes for our selftests. Thanks to: Aravinda Prasad, Breno Leitao, Camelia Groza, Christophe Leroy, Felipe Rechia, Joel Stanley, Naveen N. Rao, Paul Mackerras, Scott Wood, Tyrel Datwyler" * tag 'powerpc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (21 commits) selftests/powerpc: Fix compilation issue due to asm label selftests/powerpc/cache_shape: Fix out-of-tree build selftests/powerpc/switch_endian: Fix out-of-tree build selftests/powerpc/pmu: Link ebb tests with -no-pie selftests/powerpc/signal: Fix out-of-tree build selftests/powerpc/ptrace: Fix out-of-tree build powerpc/xmon: Relax frame size for clang selftests: powerpc: Fix warning for security subdir selftests/powerpc: Relax L1d miss targets for rfi_flush test powerpc/process: Fix flush_all_to_thread for SPE powerpc/pseries: add missing cpumask.h include file selftests/powerpc: Fix ptrace tm failure KVM: PPC: Use exported tb_to_ns() function in decrementer emulation powerpc/pseries: Export maximum memory value powerpc/8xx: Use patch_site for perf counters setup powerpc/8xx: Use patch_site for memory setup patching powerpc/code-patching: Add a helper to get the address of a patch_site Revert "powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP" powerpc/8xx: add missing header in 8xx_mmu.c powerpc/8xx: Add DT node for using the SEC engine of the MPC885 ...
| * KVM: PPC: Use exported tb_to_ns() function in decrementer emulationPaul Mackerras2018-10-262-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | This changes the KVM code that emulates the decrementer function to do the conversion of decrementer values to time intervals in nanoseconds by calling the tb_to_ns() function exported by the powerpc timer code, in preference to open-coded arithmetic using values from the decrementer_clockevent struct. Similarly, the HV-KVM code that did the same conversion using arithmetic on tb_ticks_per_sec also now uses tb_to_ns(). Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Merge tag 'powerpc-4.20-1' of ↵Linus Torvalds2018-10-261-2/+0
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Notable changes: - A large series to rewrite our SLB miss handling, replacing a lot of fairly complicated asm with much fewer lines of C. - Following on from that, we now maintain a cache of SLB entries for each process and preload them on context switch. Leading to a 27% speedup for our context switch benchmark on Power9. - Improvements to our handling of SLB multi-hit errors. We now print more debug information when they occur, and try to continue running by flushing the SLB and reloading, rather than treating them as fatal. - Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9). - Add support for physical memory up to 2PB in the linear mapping on 64-bit Book3S. We only support up to 512TB as regular system memory, otherwise the percpu allocator runs out of vmalloc space. - Add stack protector support for 32 and 64-bit, with a per-task canary. - Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP. - Support recognising "big cores" on Power9, where two SMT4 cores are presented to us as a single SMT8 core. - A large series to cleanup some of our ioremap handling and PTE flags. - Add a driver for the PAPR SCM (storage class memory) interface, allowing guests to operate on SCM devices (acked by Dan). - Changes to our ftrace code to handle very large kernels, where we need to use a trampoline to get to ftrace_caller(). And many other smaller enhancements and cleanups. Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy, Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao, Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann, Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab, Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang" * tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits) Revert "selftests/powerpc: Fix out-of-tree build errors" powerpc/msi: Fix compile error on mpc83xx powerpc: Fix stack protector crashes on CPU hotplug powerpc/traps: restore recoverability of machine_check interrupts powerpc/64/module: REL32 relocation range check powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd selftests/powerpc: Add a test of wild bctr powerpc/mm: Fix page table dump to work on Radix powerpc/mm/radix: Display if mappings are exec or not powerpc/mm/radix: Simplify split mapping logic powerpc/mm/radix: Remove the retry in the split mapping logic powerpc/mm/radix: Fix small page at boundary when splitting powerpc/mm/radix: Fix overuse of small pages in splitting logic powerpc/mm/radix: Fix off-by-one in split mapping logic powerpc/ftrace: Handle large kernel configs powerpc/mm: Fix WARN_ON with THP NUMA migration selftests/powerpc: Fix out-of-tree build errors powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64 powerpc/time: isolate scaled cputime accounting in dedicated functions. ...
| * powerpc: Add -Werror at arch/powerpc levelMichael Ellerman2018-10-191-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Back when I added -Werror in commit ba55bd74360e ("powerpc: Add configurable -Werror for arch/powerpc") I did it by adding it to most of the arch Makefiles. At the time we excluded math-emu, because apparently it didn't build cleanly. But that seems to have been fixed somewhere in the interim. So move the -Werror addition to the top-level of the arch, this saves us from repeating it in every Makefile and means we won't forget to add it to any new sub-dirs. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* | Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2018-10-2525-882/+3645
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Radim Krčmář: "ARM: - Improved guest IPA space support (32 to 52 bits) - RAS event delivery for 32bit - PMU fixes - Guest entry hardening - Various cleanups - Port of dirty_log_test selftest PPC: - Nested HV KVM support for radix guests on POWER9. The performance is much better than with PR KVM. Migration and arbitrary level of nesting is supported. - Disable nested HV-KVM on early POWER9 chips that need a particular hardware bug workaround - One VM per core mode to prevent potential data leaks - PCI pass-through optimization - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base s390: - Initial version of AP crypto virtualization via vfio-mdev - Improvement for vfio-ap - Set the host program identifier - Optimize page table locking x86: - Enable nested virtualization by default - Implement Hyper-V IPI hypercalls - Improve #PF and #DB handling - Allow guests to use Enlightened VMCS - Add migration selftests for VMCS and Enlightened VMCS - Allow coalesced PIO accesses - Add an option to perform nested VMCS host state consistency check through hardware - Automatic tuning of lapic_timer_advance_ns - Many fixes, minor improvements, and cleanups" * tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned Revert "kvm: x86: optimize dr6 restore" KVM: PPC: Optimize clearing TCEs for sparse tables x86/kvm/nVMX: tweak shadow fields selftests/kvm: add missing executables to .gitignore KVM: arm64: Safety check PSTATE when entering guest and handle IL KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips arm/arm64: KVM: Enable 32 bits kvm vcpu events support arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension() KVM: arm64: Fix caching of host MDCR_EL2 value KVM: VMX: enable nested virtualization by default KVM/x86: Use 32bit xor to clear registers in svm.c kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD kvm: vmx: Defer setting of DR6 until #DB delivery kvm: x86: Defer setting of CR2 until #PF delivery kvm: x86: Add payload operands to kvm_multiple_exception kvm: x86: Add exception payload fields to kvm_vcpu_events kvm: x86: Add has_payload and payload to kvm_queued_exception KVM: Documentation: Fix omission in struct kvm_vcpu_events KVM: selftests: add Enlightened VMCS test ...
| * | KVM: PPC: Optimize clearing TCEs for sparse tablesAlexey Kardashevskiy2018-10-202-6/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The powernv platform maintains 2 TCE tables for VFIO - a hardware TCE table and a table with userspace addresses. These tables are radix trees, we allocate indirect levels when they are written to. Since the memory allocation is problematic in real mode, we have 2 accessors to the entries: - for virtual mode: it allocates the memory and it is always expected to return non-NULL; - fr real mode: it does not allocate and can return NULL. Also, DMA windows can span to up to 55 bits of the address space and since we never have this much RAM, such windows are sparse. However currently the SPAPR TCE IOMMU driver walks through all TCEs to unpin DMA memory. Since we maintain a userspace addresses table for VFIO which is a mirror of the hardware table, we can use it to know which parts of the DMA window have not been mapped and skip these so does this patch. The bare metal systems do not have this problem as they use a bypass mode of a PHB which maps RAM directly. This helps a lot with sparse DMA windows, reducing the shutdown time from about 3 minutes per 1 billion TCEs to a few seconds for 32GB sparse guest. Just skipping the last level seems to be good enough. As non-allocating accessor is used now in virtual mode as well, rename it from IOMMU_TABLE_USERSPACE_ENTRY_RM (real mode) to _RO (read only). Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chipsPaul Mackerras2018-10-191-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This disables the use of the streamlined entry path for radix guests on early POWER9 chips that need the workaround added in commit a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with KVM", 2017-07-24), because the streamlined entry path does not include that workaround. This also means that we can't do nested HV-KVM on those chips. Since the chips that need that workaround are the same ones that can't run both radix and HPT guests at the same time on different threads of a core, we use the existing 'no_mixing_hpt_and_radix' variable that identifies those chips to identify when we can't use the new guest entry path, and when we can't do nested virtualization. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | KVM: PPC: Book3S HV: Add NO_HASH flag to GET_SMMU_INFO ioctl resultPaul Mackerras2018-10-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a KVM_PPC_NO_HASH flag to the flags field of the kvm_ppc_smmu_info struct, and arranges for it to be set when running as a nested hypervisor, as an unambiguous indication to userspace that HPT guests are not supported. Reporting the KVM_CAP_PPC_MMU_HASH_V3 capability as false could be taken as indicating only that the new HPT features in ISA V3.0 are not supported, leaving it ambiguous whether pre-V3.0 HPT features are supported. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | KVM: PPC: Book3S HV: Add a VM capability to enable nested virtualizationPaul Mackerras2018-10-092-9/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With this, userspace can enable a KVM-HV guest to run nested guests under it. The administrator can control whether any nested guests can be run; setting the "nested" module parameter to false prevents any guests becoming nested hypervisors (that is, any attempt to enable the nested capability on a guest will fail). Guests which are already nested hypervisors will continue to be so. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | Merge remote-tracking branch 'remotes/powerpc/topic/ppc-kvm' into kvm-ppc-nextPaul Mackerras2018-10-0925-876/+3583
| |\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This merges in the "ppc-kvm" topic branch of the powerpc tree to get a series of commits that touch both general arch/powerpc code and KVM code. These commits will be merged both via the KVM tree and the powerpc tree. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| | * | KVM: PPC: Book3S HV: Add nested shadow page tables to debugfsPaul Mackerras2018-10-092-3/+51
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a list of valid shadow PTEs for each nested guest to the 'radix' file for the guest in debugfs. This can be useful for debugging. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Allow HV module to load without hypervisor modePaul Mackerras2018-10-092-5/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With this, the KVM-HV module can be loaded in a guest running under KVM-HV, and if the hypervisor supports nested virtualization, this guest can now act as a nested hypervisor and run nested guests. This also adds some checks to inform userspace that HPT guests are not supported by nested hypervisors (by returning false for the KVM_CAP_PPC_MMU_HASH_V3 capability), and to prevent userspace from configuring a guest to use HPT mode. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Handle differing endianness for H_ENTER_NESTEDSuraj Jitindar Singh2018-10-091-1/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The hcall H_ENTER_NESTED takes two parameters: the address in L1 guest memory of a hv_regs struct and the address of a pt_regs struct. The hcall requests the L0 hypervisor to use the register values in these structs to run a L2 guest and to return the exit state of the L2 guest in these structs. These are in the endianness of the L1 guest, rather than being always big-endian as is usually the case for PAPR hypercalls. This is convenient because it means that the L1 guest can pass the address of the regs field in its kvm_vcpu_arch struct. This also improves performance slightly by avoiding the need for two copies of the pt_regs struct. When reading/writing these structures, this patch handles the case where the endianness of the L1 guest differs from that of the L0 hypervisor, by byteswapping the structures after reading and before writing them back. Since all the fields of the pt_regs are of the same type, i.e., unsigned long, we treat it as an array of unsigned longs. The fields of struct hv_guest_state are not all the same, so its fields are byteswapped individually. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Sanitise hv_regs on nested guest entrySuraj Jitindar Singh2018-10-091-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | restore_hv_regs() is used to copy the hv_regs L1 wants to set to run the nested (L2) guest into the vcpu structure. We need to sanitise these values to ensure we don't let the L1 guest hypervisor do things we don't want it to. We don't let data address watchpoints or completed instruction address breakpoints be set to match in hypervisor state. We also don't let L1 enable features in the hypervisor facility status and control register (HFSCR) for L2 which we have disabled for L1. That is L2 will get the subset of features which the L0 hypervisor has enabled for L1 and the features L1 wants to enable for L2. This could mean we give L1 a hypervisor facility unavailable interrupt for a facility it thinks it has enabled, however it shouldn't have enabled a facility it itself doesn't have for the L2 guest. We sanitise the registers when copying in the L2 hv_regs. We don't need to sanitise when copying back the L1 hv_regs since these shouldn't be able to contain invalid values as they're just what was copied out. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Add one-reg interface to virtual PTCR registerPaul Mackerras2018-10-091-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a one-reg register identifier which can be used to read and set the virtual PTCR for the guest. This register identifies the address and size of the virtual partition table for the guest, which contains information about the nested guests under this guest. Migrating this value is the only extra requirement for migrating a guest which has nested guests (assuming of course that the destination host supports nested virtualization in the kvm-hv module). Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Don't access HFSCR, LPIDR or LPCR when running nestedPaul Mackerras2018-10-092-16/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running as a nested hypervisor, this avoids reading hypervisor privileged registers (specifically HFSCR, LPIDR and LPCR) at startup; instead reasonable default values are used. This also avoids writing LPIDR in the single-vcpu entry/exit path. Also, this removes the check for CPU_FTR_HVMODE in kvmppc_mmu_hv_init() since its only caller already checks this. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Invalidate TLB when nested vcpu moves physical cpuSuraj Jitindar Singh2018-10-092-38/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is only done at level 0, since only level 0 knows which physical CPU a vcpu is running on. This does for nested guests what L0 already did for its own guests, which is to flush the TLB on a pCPU when it goes to run a vCPU there, and there is another vCPU in the same VM which previously ran on this pCPU and has now started to run on another pCPU. This is to handle the situation where the other vCPU touched a mapping, moved to another pCPU and did a tlbiel (local-only tlbie) on that new pCPU and thus left behind a stale TLB entry on this pCPU. This introduces a limit on the the vcpu_token values used in the H_ENTER_NESTED hcall -- they must now be less than NR_CPUS. [paulus@ozlabs.org - made prev_cpu array be short[] to reduce memory consumption.] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Use hypercalls for TLB invalidation when nestedPaul Mackerras2018-10-092-8/+52
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds code to call the H_TLB_INVALIDATE hypercall when running as a guest, in the cases where we need to invalidate TLBs (or other MMU caches) as part of managing the mappings for a nested guest. Calling H_TLB_INVALIDATE lets the nested hypervisor inform the parent hypervisor about changes to partition-scoped page tables or the partition table without needing to do hypervisor-privileged tlbie instructions. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Implement H_TLB_INVALIDATE hcallSuraj Jitindar Singh2018-10-093-2/+198
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running a nested (L2) guest the guest (L1) hypervisor will use the H_TLB_INVALIDATE hcall when it needs to change the partition scoped page tables or the partition table which it manages. It will use this hcall in the situations where it would use a partition-scoped tlbie instruction if it were running in hypervisor mode. The H_TLB_INVALIDATE hcall can invalidate different scopes: Invalidate TLB for a given target address: - This invalidates a single L2 -> L1 pte - We need to invalidate any L2 -> L0 shadow_pgtable ptes which map the L2 address space which is being invalidated. This is because a single L2 -> L1 pte may have been mapped with more than one pte in the L2 -> L0 page tables. Invalidate the entire TLB for a given LPID or for all LPIDs: - Invalidate the entire shadow_pgtable for a given nested guest, or for all nested guests. Invalidate the PWC (page walk cache) for a given LPID or for all LPIDs: - We don't cache the PWC, so nothing to do. Invalidate the entire TLB, PWC and partition table for a given/all LPIDs: - Here we re-read the partition table entry and remove the nested state for any nested guest for which the first doubleword of the partition table entry is now zero. The H_TLB_INVALIDATE hcall takes as parameters the tlbie instruction word (of which only the RIC, PRS and R fields are used), the rS value (giving the lpid, where required) and the rB value (giving the IS, AP and EPN values). [paulus@ozlabs.org - adapted to having the partition table in guest memory, added the H_TLB_INVALIDATE implementation, removed tlbie instruction emulation, reworded the commit message.] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Introduce rmap to track nested guest mappingsSuraj Jitindar Singh2018-10-093-14/+169
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a host (L0) page which is mapped into a (L1) guest is in turn mapped through to a nested (L2) guest we keep a reverse mapping (rmap) so that these mappings can be retrieved later. Whenever we create an entry in a shadow_pgtable for a nested guest we create a corresponding rmap entry and add it to the list for the L1 guest memslot at the index of the L1 guest page it maps. This means at the L1 guest memslot we end up with lists of rmaps. When we are notified of a host page being invalidated which has been mapped through to a (L1) guest, we can then walk the rmap list for that guest page, and find and invalidate all of the corresponding shadow_pgtable entries. In order to reduce memory consumption, we compress the information for each rmap entry down to 52 bits -- 12 bits for the LPID and 40 bits for the guest real page frame number -- which will fit in a single unsigned long. To avoid a scenario where a guest can trigger unbounded memory allocations, we scan the list when adding an entry to see if there is already an entry with the contents we need. This can occur, because we don't ever remove entries from the middle of a list. A struct nested guest rmap is a list pointer and an rmap entry; ---------------- | next pointer | ---------------- | rmap entry | ---------------- Thus the rmap pointer for each guest frame number in the memslot can be either NULL, a single entry, or a pointer to a list of nested rmap entries. gfn memslot rmap array ------------------------- 0 | NULL | (no rmap entry) ------------------------- 1 | single rmap entry | (rmap entry with low bit set) ------------------------- 2 | list head pointer | (list of rmap entries) ------------------------- The final entry always has the lowest bit set and is stored in the next pointer of the last list entry, or as a single rmap entry. With a list of rmap entries looking like; ----------------- ----------------- ------------------------- | list head ptr | ----> | next pointer | ----> | single rmap entry | ----------------- ----------------- ------------------------- | rmap entry | | rmap entry | ----------------- ------------------------- Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Handle page fault for a nested guestSuraj Jitindar Singh2018-10-092-86/+440
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Consider a normal (L1) guest running under the main hypervisor (L0), and then a nested guest (L2) running under the L1 guest which is acting as a nested hypervisor. L0 has page tables to map the address space for L1 providing the translation from L1 real address -> L0 real address; L1 | | (L1 -> L0) | ----> L0 There are also page tables in L1 used to map the address space for L2 providing the translation from L2 real address -> L1 read address. Since the hardware can only walk a single level of page table, we need to maintain in L0 a "shadow_pgtable" for L2 which provides the translation from L2 real address -> L0 real address. Which looks like; L2 L2 | | | (L2 -> L1) | | | ----> L1 | (L2 -> L0) | | | (L1 -> L0) | | | ----> L0 --------> L0 When a page fault occurs while running a nested (L2) guest we need to insert a pte into this "shadow_pgtable" for the L2 -> L0 mapping. To do this we need to: 1. Walk the pgtable in L1 memory to find the L2 -> L1 mapping, and provide a page fault to L1 if this mapping doesn't exist. 2. Use our L1 -> L0 pgtable to convert this L1 address to an L0 address, or try to insert a pte for that mapping if it doesn't exist. 3. Now we have a L2 -> L0 mapping, insert this into our shadow_pgtable Once this mapping exists we can take rc faults when hardware is unable to automatically set the reference and change bits in the pte. On these we need to: 1. Check the rc bits on the L2 -> L1 pte match, and otherwise reflect the fault down to L1. 2. Set the rc bits in the L1 -> L0 pte which corresponds to the same host page. 3. Set the rc bits in the L2 -> L0 pte. As we reuse a large number of functions in book3s_64_mmu_radix.c for this we also needed to refactor a number of these functions to take an lpid parameter so that the correct lpid is used for tlb invalidations. The functionality however has remained the same. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Handle hypercalls correctly when nestedPaul Mackerras2018-10-093-1/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we are running as a nested hypervisor, we use a hypercall to enter the guest rather than code in book3s_hv_rmhandlers.S. This means that the hypercall handlers listed in hcall_real_table never get called. There are some hypercalls that are handled there and not in kvmppc_pseries_do_hcall(), which therefore won't get processed for a nested guest. To fix this, we add cases to kvmppc_pseries_do_hcall() to handle those hypercalls, with the following exceptions: - The HPT hypercalls (H_ENTER, H_REMOVE, etc.) are not handled because we only support radix mode for nested guests. - H_CEDE has to be handled specially because the cede logic in kvmhv_run_single_vcpu assumes that it has been processed by the time that kvmhv_p9_guest_entry() returns. Therefore we put a special case for H_CEDE in kvmhv_p9_guest_entry(). For the XICS hypercalls, if real-mode processing is enabled, then the virtual-mode handlers assume that they are being called only to finish up the operation. Therefore we turn off the real-mode flag in the XICS code when running as a nested hypervisor. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Use XICS hypercalls when running as a nested hypervisorPaul Mackerras2018-10-093-9/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds code to call the H_IPI and H_EOI hypercalls when we are running as a nested hypervisor (i.e. without the CPU_FTR_HVMODE cpu feature) and we would otherwise access the XICS interrupt controller directly or via an OPAL call. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Nested guest entry via hypercallPaul Mackerras2018-10-093-30/+422
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a new hypercall, H_ENTER_NESTED, which is used by a nested hypervisor to enter one of its nested guests. The hypercall supplies register values in two structs. Those values are copied by the level 0 (L0) hypervisor (the one which is running in hypervisor mode) into the vcpu struct of the L1 guest, and then the guest is run until an interrupt or error occurs which needs to be reported to L1 via the hypercall return value. Currently this assumes that the L0 and L1 hypervisors are the same endianness, and the structs passed as arguments are in native endianness. If they are of different endianness, the version number check will fail and the hcall will be rejected. Nested hypervisors do not support indep_threads_mode=N, so this adds code to print a warning message if the administrator has set indep_threads_mode=N, and treat it as Y. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Framework and hcall stubs for nested virtualizationPaul Mackerras2018-10-093-4/+331
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This starts the process of adding the code to support nested HV-style virtualization. It defines a new H_SET_PARTITION_TABLE hypercall which a nested hypervisor can use to set the base address and size of a partition table in its memory (analogous to the PTCR register). On the host (level 0 hypervisor) side, the H_SET_PARTITION_TABLE hypercall from the guest is handled by code that saves the virtual PTCR value for the guest. This also adds code for creating and destroying nested guests and for reading the partition table entry for a nested guest from L1 memory. Each nested guest has its own shadow LPID value, different in general from the LPID value used by the nested hypervisor to refer to it. The shadow LPID value is allocated at nested guest creation time. Nested hypervisor functionality is only available for a radix guest, which therefore means a radix host on a POWER9 (or later) processor. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Use kvmppc_unmap_pte() in kvm_unmap_radix()Paul Mackerras2018-10-091-20/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kvmppc_unmap_pte() does a sequence of operations that are open-coded in kvm_unmap_radix(). This extends kvmppc_unmap_pte() a little so that it can be used by kvm_unmap_radix(), and makes kvm_unmap_radix() call it. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Refactor radix page fault handlerSuraj Jitindar Singh2018-10-091-87/+123
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The radix page fault handler accounts for all cases, including just needing to insert a pte. This breaks it up into separate functions for the two main cases; setting rc and inserting a pte. This allows us to make the setting of rc and inserting of a pte generic for any pgtable, not specific to the one for this guest. [paulus@ozlabs.org - reduced diffs from previous code] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Make kvmppc_mmu_radix_xlate process/partition table ↵Suraj Jitindar Singh2018-10-091-34/+75
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | agnostic kvmppc_mmu_radix_xlate() is used to translate an effective address through the process tables. The process table and partition tables have identical layout. Exploit this fact to make the kvmppc_mmu_radix_xlate() function able to translate either an effective address through the process tables or a guest real address through the partition tables. [paulus@ozlabs.org - reduced diffs from previous code] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Clear partition table entry on vm teardownSuraj Jitindar Singh2018-10-091-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When destroying a VM we return the LPID to the pool, however we never zero the partition table entry. This is instead done when we reallocate the LPID. Zero the partition table entry on VM teardown before returning the LPID to the pool. This means if we were running as a nested hypervisor the real hypervisor could use this to determine when it can free resources. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Use ccr field in pt_regs struct embedded in vcpu structPaul Mackerras2018-10-098-22/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the 'regs' field was added to struct kvm_vcpu_arch, the code was changed to use several of the fields inside regs (e.g., gpr, lr, etc.) but not the ccr field, because the ccr field in struct pt_regs is 64 bits on 64-bit platforms, but the cr field in kvm_vcpu_arch is only 32 bits. This changes the code to use the regs.ccr field instead of cr, and changes the assembly code on 64-bit platforms to use 64-bit loads and stores instead of 32-bit ones. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Add a debugfs file to dump radix mappingsPaul Mackerras2018-10-092-0/+181
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a file called 'radix' in the debugfs directory for the guest, which when read gives all of the valid leaf PTEs in the partition-scoped radix tree for a radix guest, in human-readable format. It is analogous to the existing 'htab' file which dumps the HPT entries for a HPT guest. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Handle hypervisor instruction faults betterPaul Mackerras2018-10-091-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the code for handling hypervisor instruction page faults passes 0 for the flags indicating the type of fault, which is OK in the usual case that the page is not mapped in the partition-scoped page tables. However, there are other causes for hypervisor instruction page faults, such as not being to update a reference (R) or change (C) bit. The cause is indicated in bits in HSRR1, including a bit which indicates that the fault is due to not being able to write to a page (for example to update an R or C bit). Not handling these other kinds of faults correctly can lead to a loop of continual faults without forward progress in the guest. In order to handle these faults better, this patch constructs a "DSISR-like" value from the bits which DSISR and SRR1 (for a HISI) have in common, and passes it to kvmppc_book3s_hv_page_fault() so that it knows what caused the fault. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guestsPaul Mackerras2018-10-094-4/+589
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This creates an alternative guest entry/exit path which is used for radix guests on POWER9 systems when we have indep_threads_mode=Y. In these circumstances there is exactly one vcpu per vcore and there is no coordination required between vcpus or vcores; the vcpu can enter the guest without needing to synchronize with anything else. The new fast path is implemented almost entirely in C in book3s_hv.c and runs with the MMU on until the guest is entered. On guest exit we use the existing path until the point where we are committed to exiting the guest (as distinct from handling an interrupt in the low-level code and returning to the guest) and we have pulled the guest context from the XIVE. At that point we check a flag in the stack frame to see whether we came in via the old path and the new path; if we came in via the new path then we go back to C code to do the rest of the process of saving the guest context and restoring the host context. The C code is split into separate functions for handling the OS-accessible state and the hypervisor state, with the idea that the latter can be replaced by a hypercall when we implement nested virtualization. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [mpe: Fix CONFIG_ALTIVEC=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Call kvmppc_handle_exit_hv() with vcore unlockedPaul Mackerras2018-10-091-9/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently kvmppc_handle_exit_hv() is called with the vcore lock held because it is called within a for_each_runnable_thread loop. However, we already unlock the vcore within kvmppc_handle_exit_hv() under certain circumstances, and this is safe because (a) any vcpus that become runnable and are added to the runnable set by kvmppc_run_vcpu() have their vcpu->arch.trap == 0 and can't actually run in the guest (because the vcore state is VCORE_EXITING), and (b) for_each_runnable_thread is safe against addition or removal of vcpus from the runnable set. Therefore, in order to simplify things for following patches, let's drop the vcore lock in the for_each_runnable_thread loop, so kvmppc_handle_exit_hv() gets called without the vcore lock held. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S: Rework TM save/restore code and make it C-callablePaul Mackerras2018-10-092-140/+159
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a parameter to __kvmppc_save_tm and __kvmppc_restore_tm which allows the caller to indicate whether it wants the nonvolatile register state to be preserved across the call, as required by the C calling conventions. This parameter being non-zero also causes the MSR bits that enable TM, FP, VMX and VSX to be preserved. The condition register and DSCR are now always preserved. With this, kvmppc_save_tm_hv and kvmppc_restore_tm_hv can be called from C code provided the 3rd parameter is non-zero. So that these functions can be called from modules, they now include code to set the TOC pointer (r2) on entry, as they can call other built-in C functions which will assume the TOC to have been set. Also, the fake suspend code in kvmppc_save_tm_hv is modified here to assume that treclaim in fake-suspend state does not modify any registers, which is the case on POWER9. This enables the code to be simplified quite a bit. _kvmppc_save_tm_pr and _kvmppc_restore_tm_pr become much simpler with this change, since they now only need to save and restore TAR and pass 1 for the 3rd argument to __kvmppc_{save,restore}_tm. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Simplify real-mode interrupt handlingPaul Mackerras2018-10-092-109/+119
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This streamlines the first part of the code that handles a hypervisor interrupt that occurred in the guest. With this, all of the real-mode handling that occurs is done before the "guest_exit_cont" label; once we get to that label we are committed to exiting to host virtual mode. Thus the machine check and HMI real-mode handling is moved before that label. Also, the code to handle external interrupts is moved out of line, as is the code that calls kvmppc_realmode_hmi_handler(). Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Extract PMU save/restore operations as C-callable functionsPaul Mackerras2018-10-092-210/+248
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This pulls out the assembler code that is responsible for saving and restoring the PMU state for the host and guest into separate functions so they can be used from an alternate entry path. The calling convention is made compatible with C. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Move interrupt delivery on guest entry to C codePaul Mackerras2018-10-093-55/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is based on a patch by Suraj Jitindar Singh. This moves the code in book3s_hv_rmhandlers.S that generates an external, decrementer or privileged doorbell interrupt just before entering the guest to C code in book3s_hv_builtin.c. This is to make future maintenance and modification easier. The algorithm expressed in the C code is almost identical to the previous algorithm. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S HV: Remove left-over code in XICS-on-XIVE emulationPaul Mackerras2018-10-091-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This removes code that clears the external interrupt pending bit in the pending_exceptions bitmap. This is left over from an earlier iteration of the code where this bit was set when an escalation interrupt arrived in order to wake the vcpu from cede. Currently we set the vcpu->arch.irq_pending flag instead for this purpose. Therefore there is no need to do anything with the pending_exceptions bitmap. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Book3S: Simplify external interrupt handlingPaul Mackerras2018-10-097-25/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently we use two bits in the vcpu pending_exceptions bitmap to indicate that an external interrupt is pending for the guest, one for "one-shot" interrupts that are cleared when delivered, and one for interrupts that persist until cleared by an explicit action of the OS (e.g. an acknowledge to an interrupt controller). The BOOK3S_IRQPRIO_EXTERNAL bit is used for one-shot interrupt requests and BOOK3S_IRQPRIO_EXTERNAL_LEVEL is used for persisting interrupts. In practice BOOK3S_IRQPRIO_EXTERNAL never gets used, because our Book3S platforms generally, and pseries in particular, expect external interrupt requests to persist until they are acknowledged at the interrupt controller. That combined with the confusion introduced by having two bits for what is essentially the same thing makes it attractive to simplify things by only using one bit. This patch does that. With this patch there is only BOOK3S_IRQPRIO_EXTERNAL, and by default it has the semantics of a persisting interrupt. In order to avoid breaking the ABI, we introduce a new "external_oneshot" flag which preserves the behaviour of the KVM_INTERRUPT ioctl with the KVM_INTERRUPT_SET argument. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Remove redundand permission bits removalAlexey Kardashevskiy2018-10-092-21/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kvmppc_gpa_to_ua() helper itself takes care of the permission bits in the TCE and yet every single caller removes them. This changes semantics of kvmppc_gpa_to_ua() so it takes TCEs (which are GPAs + TCE permission bits) to make the callers simpler. This should cause no behavioural change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Propagate errors to the guest when failed instead of ignoringAlexey Kardashevskiy2018-10-092-28/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the moment if the PUT_TCE{_INDIRECT} handlers fail to update the hardware tables, we print a warning once, clear the entry and continue. This is so as at the time the assumption was that if a VFIO device is hotplugged into the guest, and the userspace replays virtual DMA mappings (i.e. TCEs) to the hardware tables and if this fails, then there is nothing useful we can do about it. However the assumption is not valid as these handlers are not called for TCE replay (VFIO ioctl interface is used for that) and these handlers are for new TCEs. This returns an error to the guest if there is a request which cannot be processed. By now the only possible failure must be H_TOO_HARD. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Validate TCEs against preregistered memory page sizesAlexey Kardashevskiy2018-10-092-7/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The userspace can request an arbitrary supported page size for a DMA window and this works fine as long as the mapped memory is backed with the pages of the same or bigger size; if this is not the case, mm_iommu_ua_to_hpa{_rm}() fail and tables do not populated with dangerously incorrect TCEs. However since it is quite easy to misconfigure the KVM and we do not do reverts to all changes made to TCE tables if an error happens in a middle, we better do the acceptable page size validation before we even touch the tables. This enhances kvmppc_tce_validate() to check the hardware IOMMU page sizes against the preregistered memory page sizes. Since the new check uses real/virtual mode helpers, this renames kvmppc_tce_validate() to kvmppc_rm_tce_validate() to handle the real mode case and mirrors it for the virtual mode under the old name. The real mode handler is not used for the virtual mode as: 1. it uses _lockless() list traversing primitives instead of RCU; 2. realmode's mm_iommu_ua_to_hpa_rm() uses vmalloc_to_phys() which virtual mode does not have to use and since on POWER9+radix only virtual mode handlers actually work, we do not want to slow down that path even a bit. This removes EXPORT_SYMBOL_GPL(kvmppc_tce_validate) as the validators are static now. From now on the attempts on mapping IOMMU pages bigger than allowed will result in KVM exit. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [mpe: Fix KVM_HV=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Inform the userspace about TCE update failuresAlexey Kardashevskiy2018-10-022-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We return H_TOO_HARD from TCE update handlers when we think that the next handler (realmode -> virtual mode -> user mode) has a chance to handle the request; H_HARDWARE/H_CLOSED otherwise. This changes the handlers to return H_TOO_HARD on every error giving the userspace an opportunity to handle any request or at least log them all. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| | * | KVM: PPC: Validate all tces before updating tablesAlexey Kardashevskiy2018-10-022-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The KVM TCE handlers are written in a way so they fail when either something went horribly wrong or the userspace did some obvious mistake such as passing a misaligned address. We are going to enhance the TCE checker to fail on attempts to map bigger IOMMU page than the underlying pinned memory so let's valitate TCE beforehand. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
| * | | KVM: PPC: Book3S HV: Provide mode where all vCPUs on a core must be the same VMPaul Mackerras2018-10-051-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a mode where the vcore scheduling logic in HV KVM limits itself to scheduling only virtual cores from the same VM on any given physical core. This is enabled via a new module parameter on the kvm-hv module called "one_vm_per_core". For this to work on POWER9, it is necessary to set indep_threads_mode=N. (On POWER8, hardware limitations mean that KVM is never in independent threads mode, regardless of the indep_threads_mode setting.) Thus the settings needed for this to work are: 1. The host is in SMT1 mode. 2. On POWER8, the host is not in 2-way or 4-way static split-core mode. 3. On POWER9, the indep_threads_mode parameter is N. 4. The one_vm_per_core parameter is Y. With these settings, KVM can run up to 4 vcpus on a core at the same time on POWER9, or up to 8 vcpus on POWER8 (depending on the guest threading mode), and will ensure that all of the vcpus belong to the same VM. This is intended for use in security-conscious settings where users are concerned about possible side-channel attacks between threads which could perhaps enable one VM to attack another VM on the same core, or the host. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| * | | KVM: PPC: Book3S PR: Exiting split hack mode needs to fixup both PC and LRCameron Kaiser2018-10-051-0/+3
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an OS (currently only classic Mac OS) is running in KVM-PR and makes a linked jump from code with split hack addressing enabled into code that does not, LR is not correctly updated and reflects the previously munged PC. To fix this, this patch undoes the address munge when exiting split hack mode so that code relying on LR being a proper address will now execute. This does not affect OS X or other operating systems running on KVM-PR. Signed-off-by: Cameron Kaiser <spectre@floodgap.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* | | KVM: PPC: Book3S HV: Avoid crash from THP collapse during radix page faultPaul Mackerras2018-10-041-0/+10
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 71d29f43b633 ("KVM: PPC: Book3S HV: Don't use compound_order to determine host mapping size", 2018-09-11) added a call to __find_linux_pte() and a dereference of the returned PTE pointer to the radix page fault path in the common case where the page is normal system memory. Previously, __find_linux_pte() was only called for mappings to physical addresses which don't have a page struct (e.g. memory-mapped I/O) or where the page struct is marked as reserved memory. This exposes us to the possibility that the returned PTE pointer could be NULL, for example in the case of a concurrent THP collapse operation. Dereferencing the returned NULL pointer causes a host crash. To fix this, we check for NULL, and if it is NULL, we retry the operation by returning to the guest, with the expectation that it will generate the same page fault again (unless of course it has been fixed up by another CPU in the meantime). Fixes: 71d29f43b633 ("KVM: PPC: Book3S HV: Don't use compound_order to determine host mapping size") Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
* | KVM: PPC: Book3S HV: Don't use compound_order to determine host mapping sizeNicholas Piggin2018-09-121-54/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | THP paths can defer splitting compound pages until after the actual remap and TLB flushes to split a huge PMD/PUD. This causes radix partition scope page table mappings to get out of synch with the host qemu page table mappings. This results in random memory corruption in the guest when running with THP. The easiest way to reproduce is use KVM balloon to free up a lot of memory in the guest and then shrink the balloon to give the memory back, while some work is being done in the guest. Cc: David Gibson <david@gibson.dropbear.id.au> Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Cc: kvm-ppc@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
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