aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kvm/book3s_hv_rmhandlers.S (follow)
AgeCommit message (Collapse)AuthorFilesLines
2016-03-22KVM: PPC: Create a virtual-mode only TCE table handlersAlexey Kardashevskiy1-2/+2
Upcoming in-kernel VFIO acceleration needs different handling in real and virtual modes which makes it hard to support both modes in the same handler. This creates a copy of kvmppc_rm_h_stuff_tce and kvmppc_rm_h_put_tce in addition to the existing kvmppc_rm_h_put_tce_indirect. This also fixes linker breakage when only PR KVM was selected (leaving HV KVM off): the kvmppc_h_put_tce/kvmppc_h_stuff_tce functions would not compile at all and the linked would fail. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-19Merge tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linuxLinus Torvalds1-1/+1
Pull powerpc updates from Michael Ellerman: "This was delayed a day or two by some build-breakage on old toolchains which we've now fixed. There's two PCI commits both acked by Bjorn. There's one commit to mm/hugepage.c which is (co)authored by Kirill. Highlights: - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V - Add POWER9 cputable entry from Michael Neuling - FPU/Altivec/VSX save/restore optimisations from Cyril Bur - Add support for new ftrace ABI on ppc64le from Torsten Duwe Various cleanups & minor fixes from: - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh. General: - atomics: Allow architectures to define their own __atomic_op_* helpers from Boqun Feng - Implement atomic{, 64}_*_return_* variants and acquire/release/ relaxed variants for (cmp)xchg from Boqun Feng - Add powernv_defconfig from Jeremy Kerr - Fix BUG_ON() reporting in real mode from Balbir Singh - Add xmon command to dump OPAL msglog from Andrew Donnellan - Add xmon command to dump process/task similar to ps(1) from Douglas Miller - Clean up memory hotplug failure paths from David Gibson pci/eeh: - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei Yang. - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan. - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang - PCI: Add pcibios_bus_add_device() weak function from Wei Yang - MAINTAINERS: Update EEH details and maintainership from Russell Currey cxl: - Support added to the CXL driver for running on both bare-metal and hypervisor systems, from Christophe Lombard and Frederic Barrat. - Ignore probes for virtual afu pci devices from Vaibhav Jain perf: - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu - hv-24x7: Fix usage with chip events, display change in counter values, display domain indices in sysfs, eliminate domain suffix in event names, from Sukadev Bhattiprolu Freescale: - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and other dt bits, and minor fixes/cleanup" * tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits) powerpc: Fix unrecoverable SLB miss during restore_math() powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers powerpc/rcpm: Fix build break when SMP=n powerpc/book3e-64: Use hardcoded mttmr opcode powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible powerpc/T104xRDB: add tdm riser card node to device tree powerpc32: PAGE_EXEC required for inittext powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s) powerpc/86xx: Introduce and use common dtsi powerpc/86xx: Update device tree powerpc/86xx: Move dts files to fsl directory powerpc/86xx: Switch to kconfig fragments approach powerpc/86xx: Update defconfigs powerpc/86xx: Consolidate common platform code powerpc32: Remove one insn in mulhdu powerpc32: small optimisation in flush_icache_range() powerpc: Simplify test in __dma_sync() powerpc32: move xxxxx_dcache_range() functions inline powerpc32: Remove clear_pages() and define clear_page() inline ...
2016-03-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-2/+2
Pull KVM updates from Paolo Bonzini: "One of the largest releases for KVM... Hardly any generic changes, but lots of architecture-specific updates. ARM: - VHE support so that we can run the kernel at EL2 on ARMv8.1 systems - PMU support for guests - 32bit world switch rewritten in C - various optimizations to the vgic save/restore code. PPC: - enabled KVM-VFIO integration ("VFIO device") - optimizations to speed up IPIs between vcpus - in-kernel handling of IOMMU hypercalls - support for dynamic DMA windows (DDW). s390: - provide the floating point registers via sync regs; - separated instruction vs. data accesses - dirty log improvements for huge guests - bugfixes and documentation improvements. x86: - Hyper-V VMBus hypercall userspace exit - alternative implementation of lowest-priority interrupts using vector hashing (for better VT-d posted interrupt support) - fixed guest debugging with nested virtualizations - improved interrupt tracking in the in-kernel IOAPIC - generic infrastructure for tracking writes to guest memory - currently its only use is to speedup the legacy shadow paging (pre-EPT) case, but in the future it will be used for virtual GPUs as well - much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits) KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch KVM: x86: disable MPX if host did not enable MPX XSAVE features arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit arm64: KVM: vgic-v3: Reset LRs at boot time arm64: KVM: vgic-v3: Do not save an LR known to be empty arm64: KVM: vgic-v3: Save maintenance interrupt state only if required arm64: KVM: vgic-v3: Avoid accessing ICH registers KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit KVM: arm/arm64: vgic-v2: Reset LRs at boot time KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers KVM: s390: allocate only one DMA page per VM KVM: s390: enable STFLE interpretation only if enabled for the guest KVM: s390: wake up when the VCPU cpu timer expires KVM: s390: step the VCPU timer while in enabled wait KVM: s390: protect VCPU cpu timer with a seqcount KVM: s390: step VCPU cpu timer during kvm_run ioctl ...
2016-03-08KVM: PPC: Book3S HV: Sanitize special-purpose register values on guest exitPaul Mackerras1-0/+14
Thomas Huth discovered that a guest could cause a hard hang of a host CPU by setting the Instruction Authority Mask Register (IAMR) to a suitable value. It turns out that this is because when the code was added to context-switch the new special-purpose registers (SPRs) that were added in POWER8, we forgot to add code to ensure that they were restored to a sane value on guest exit. This adds code to set those registers where a bad value could compromise the execution of the host kernel to a suitable neutral value on guest exit. Cc: stable@vger.kernel.org # v3.14+ Fixes: b005255e12a3 Reported-by: Thomas Huth <thuth@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2016-03-03powerpc/mm: Move hash related mmu-*.h headers to book3s/Aneesh Kumar K.V1-1/+1
No code changes. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-02-16KVM: PPC: Add support for multiple-TCE hcallsAlexey Kardashevskiy1-2/+2
This adds real and virtual mode handlers for the H_PUT_TCE_INDIRECT and H_STUFF_TCE hypercalls for user space emulated devices such as IBMVIO devices or emulated PCI. These calls allow adding multiple entries (up to 512) into the TCE table in one call which saves time on transition between kernel and user space. The current implementation of kvmppc_h_stuff_tce() allows it to be executed in both real and virtual modes so there is one helper. The kvmppc_rm_h_put_tce_indirect() needs to translate the guest address to the host address and since the translation is different, there are 2 helpers - one for each mode. This implements the KVM_CAP_PPC_MULTITCE capability. When present, the kernel will try handling H_PUT_TCE_INDIRECT and H_STUFF_TCE if these are enabled by the userspace via KVM_CAP_PPC_ENABLE_HCALL. If they can not be handled by the kernel, they are passed on to the user space. The user space still has to have an implementation for these. Both HV and PR-syle KVM are supported. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-09KVM: PPC: Fix emulation of H_SET_DABR/X on POWER8Thomas Huth1-1/+1
In the old DABR register, the BT (Breakpoint Translation) bit is bit number 61. In the new DAWRX register, the WT (Watchpoint Translation) bit is bit number 59. So to move the DABR-BT bit into the position of the DAWRX-WT bit, it has to be shifted by two, not only by one. This fixes hardware watchpoints in gdb of older guests that only use the H_SET_DABR/X interface instead of the new H_SET_MODE interface. Cc: stable@vger.kernel.org # v3.14+ Signed-off-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-12-09KVM: PPC: Book3S HV: Handle unexpected traps in guest entry/exit code betterPaul Mackerras1-0/+2
As we saw with the TM Bad Thing type of program interrupt occurring on the hrfid that enters the guest, it is not completely impossible to have a trap occurring in the guest entry/exit code, despite the fact that the code has been written to avoid taking any traps. This adds a check in the kvmppc_handle_exit_hv() function to detect the case when a trap has occurred in the hypervisor-mode code, and instead of treating it just like a trap in guest code, we now print a message and return to userspace with a KVM_EXIT_INTERNAL_ERROR exit reason. Of the various interrupts that get handled in the assembly code in the guest exit path and that can return directly to the guest, the only one that can occur when MSR.HV=1 and MSR.EE=0 is machine check (other than system call, which we can avoid just by not doing a sc instruction). Therefore this adds code to the machine check path to ensure that if the MCE occurred in hypervisor mode, we exit to the host rather than trying to continue the guest. Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-11-06KVM: PPC: Book3S HV: Synthesize segment fault if SLB lookup failsPaul Mackerras1-8/+12
When handling a hypervisor data or instruction storage interrupt (HDSI or HISI), we look up the SLB entry for the address being accessed in order to translate the effective address to a virtual address which can be looked up in the guest HPT. This lookup can occasionally fail due to the guest replacing an SLB entry without invalidating the evicted SLB entry. In this situation an ERAT (effective to real address translation cache) entry can persist and be used by the hardware even though there is no longer a corresponding SLB entry. Previously we would just deliver a data or instruction storage interrupt (DSI or ISI) to the guest in this case. However, this is not correct and has been observed to cause guests to crash, typically with a data storage protection interrupt on a store to the vmemmap area. Instead, what we do now is to synthesize a data or instruction segment interrupt. That should cause the guest to reload an appropriate entry into the SLB and retry the faulting instruction. If it still faults, we should find an appropriate SLB entry next time and be able to handle the fault. Tested-by: Thomas Huth <thuth@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-21KVM: PPC: Book3S HV: Handle H_DOORBELL on the guest exit pathGautham R. Shenoy1-3/+14
Currently a CPU running a guest can receive a H_DOORBELL in the following two cases: 1) When the CPU is napping due to CEDE or there not being a guest vcpu. 2) The CPU is running the guest vcpu. Case 1), the doorbell message is not cleared since we were waking up from nap. Hence when the EE bit gets set on transition from guest to host, the H_DOORBELL interrupt is delivered to the host and the corresponding handler is invoked. However in Case 2), the message gets cleared by the action of taking the H_DOORBELL interrupt. Since the CPU was running a guest, instead of invoking the doorbell handler, the code invokes the second-level interrupt handler to switch the context from the guest to the host. At this point the setting of the EE bit doesn't result in the CPU getting the doorbell interrupt since it has already been delivered once. So, the handler for this doorbell is never invoked! This causes softlockups if the missed DOORBELL was an IPI sent from a sibling subcore on the same CPU. This patch fixes it by explitly invoking the doorbell handler on the exit path if the exit reason is H_DOORBELL similar to the way an EXTERNAL interrupt is handled. Since this will also handle Case 1), we can unconditionally clear the doorbell message in kvmppc_check_wake_reason. Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-10-16KVM: PPC: Book3S HV: Deliver machine check with MSR(RI=0) to guest as MCEMahesh Salgaonkar1-4/+8
For the machine check interrupt that happens while we are in the guest, kvm layer attempts the recovery, and then delivers the machine check interrupt directly to the guest if recovery fails. On successful recovery we go back to normal functioning of the guest. But there can be cases where a machine check interrupt can happen with MSR(RI=0) while we are in the guest. This means MC interrupt is unrecoverable and we have to deliver a machine check to the guest since the machine check interrupt might have trashed valid values in SRR0/1. The current implementation do not handle this case, causing guest to crash with Bad kernel stack pointer instead of machine check oops message. [26281.490060] Bad kernel stack pointer 3fff9ccce5b0 at c00000000000490c [26281.490434] Oops: Bad kernel stack pointer, sig: 6 [#1] [26281.490472] SMP NR_CPUS=2048 NUMA pSeries This patch fixes this issue by checking MSR(RI=0) in KVM layer and forwarding unrecoverable interrupt to guest which then panics with proper machine check Oops message. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-21KVM: PPC: Book3S HV: Pass the correct trap argument to kvmhv_commence_exitGautham R. Shenoy1-0/+1
In guest_exit_cont we call kvmhv_commence_exit which expects the trap number as the argument. However r3 doesn't contain the trap number at this point and as a result we would be calling the function with a spurious trap number. Fix this by copying r12 into r3 before calling kvmhv_commence_exit as r12 contains the trap number. Cc: stable@vger.kernel.org # v4.1+ Fixes: eddb60fb1443 Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03KVM: PPC: Book3S HV: Exit on H_DOORBELL if HOST_IPI is setGautham R. Shenoy1-0/+1
The code that handles the case when we receive a H_DOORBELL interrupt has a comment which says "Hypervisor doorbell - exit only if host IPI flag set". However, the current code does not actually check if the host IPI flag is set. This is due to a comparison instruction that got missed. As a result, the current code performs the exit to host only if some sibling thread or a sibling sub-core is exiting to the host. This implies that, an IPI sent to a sibling core in (subcores-per-core != 1) mode will be missed by the host unless the sibling core is on the exit path to the host. This patch adds the missing comparison operation which will ensure that when HOST_IPI flag is set, we unconditionally exit to the host. Fixes: 66feed61cdf6 Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-09-03KVM: PPC: Book3S HV: Fix race in starting secondary threadsGautham R. Shenoy1-0/+8
The current dynamic micro-threading code has a race due to which a secondary thread naps when it is supposed to be running a vcpu. As a side effect of this, on a guest exit, the primary thread in kvmppc_wait_for_nap() finds that this secondary thread hasn't cleared its vcore pointer. This results in "CPU X seems to be stuck!" warnings. The race is possible since the primary thread on exiting the guests only waits for all the secondaries to clear its vcore pointer. It subsequently expects the secondary threads to enter nap while it unsplits the core. A secondary thread which hasn't yet entered the nap will loop in kvm_no_guest until its vcore pointer and the do_nap flag are unset. Once the core has been unsplit, a new vcpu thread can grab the core and set the do_nap flag *before* setting the vcore pointers of the secondary. As a result, the secondary thread will now enter nap via kvm_unsplit_nap instead of running the guest vcpu. Fix this by setting the do_nap flag after setting the vcore pointer in the PACA of the secondary in kvmppc_run_core. Also, ensure that a secondary thread doesn't nap in kvm_unsplit_nap when the vcore pointer in its PACA struct is set. Fixes: b4deba5c41e9 Signed-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org>
2015-08-22KVM: PPC: Book3S: correct width in XER handlingSam bobroff1-3/+3
In 64 bit kernels, the Fixed Point Exception Register (XER) is a 64 bit field (e.g. in kvm_regs and kvm_vcpu_arch) and in most places it is accessed as such. This patch corrects places where it is accessed as a 32 bit field by a 64 bit kernel. In some cases this is via a 32 bit load or store instruction which, depending on endianness, will cause either the lower or upper 32 bits to be missed. In another case it is cast as a u32, causing the upper 32 bits to be cleared. This patch corrects those places by extending the access methods to 64 bits. Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com> Reviewed-by: Laurent Vivier <lvivier@redhat.com> Reviewed-by: Thomas Huth <thuth@redhat.com> Tested-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22KVM: PPC: Book3S HV: Implement H_CLEAR_REF and H_CLEAR_MODPaul Mackerras1-2/+2
This adds implementations for the H_CLEAR_REF (test and clear reference bit) and H_CLEAR_MOD (test and clear changed bit) hypercalls. When clearing the reference or change bit in the guest view of the HPTE, we also have to clear it in the real HPTE so that we can detect future references or changes. When we do so, we transfer the R or C bit value to the rmap entry for the underlying host page so that kvm_age_hva_hv(), kvm_test_age_hva_hv() and kvmppc_hv_get_dirty_log() know that the page has been referenced and/or changed. These hypercalls are not used by Linux guests. These implementations have been tested using a FreeBSD guest. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22KVM: PPC: Book3S HV: Implement dynamic micro-threading on POWER8Paul Mackerras1-15/+98
This builds on the ability to run more than one vcore on a physical core by using the micro-threading (split-core) modes of the POWER8 chip. Previously, only vcores from the same VM could be run together, and (on POWER8) only if they had just one thread per core. With the ability to split the core on guest entry and unsplit it on guest exit, we can run up to 8 vcpu threads from up to 4 different VMs, and we can run multiple vcores with 2 or 4 vcpus per vcore. Dynamic micro-threading is only available if the static configuration of the cores is whole-core mode (unsplit), and only on POWER8. To manage this, we introduce a new kvm_split_mode struct which is shared across all of the subcores in the core, with a pointer in the paca on each thread. In addition we extend the core_info struct to have information on each subcore. When deciding whether to add a vcore to the set already on the core, we now have two possibilities: (a) piggyback the vcore onto an existing subcore, or (b) start a new subcore. Currently, when any vcpu needs to exit the guest and switch to host virtual mode, we interrupt all the threads in all subcores and switch the core back to whole-core mode. It may be possible in future to allow some of the subcores to keep executing in the guest while subcore 0 switches to the host, but that is not implemented in this patch. This adds a module parameter called dynamic_mt_modes which controls which micro-threading (split-core) modes the code will consider, as a bitmap. In other words, if it is 0, no micro-threading mode is considered; if it is 2, only 2-way micro-threading is considered; if it is 4, only 4-way, and if it is 6, both 2-way and 4-way micro-threading mode will be considered. The default is 6. With this, we now have secondary threads which are the primary thread for their subcore and therefore need to do the MMU switch. These threads will need to be started even if they have no vcpu to run, so we use the vcore pointer in the PACA rather than the vcpu pointer to trigger them. It is now possible for thread 0 to find that an exit has been requested before it gets to switch the subcore state to the guest. In that case we haven't added the guest's timebase offset to the timebase, so we need to be careful not to subtract the offset in the guest exit path. In fact we just skip the whole path that switches back to host context, since we haven't switched to the guest context. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-08-22KVM: PPC: Book3S HV: Make use of unused threads when running guestsPaul Mackerras1-0/+5
When running a virtual core of a guest that is configured with fewer threads per core than the physical cores have, the extra physical threads are currently unused. This makes it possible to use them to run one or more other virtual cores from the same guest when certain conditions are met. This applies on POWER7, and on POWER8 to guests with one thread per virtual core. (It doesn't apply to POWER8 guests with multiple threads per vcore because they require a 1-1 virtual to physical thread mapping in order to be able to use msgsndp and the TIR.) The idea is that we maintain a list of preempted vcores for each physical cpu (i.e. each core, since the host runs single-threaded). Then, when a vcore is about to run, it checks to see if there are any vcores on the list for its physical cpu that could be piggybacked onto this vcore's execution. If so, those additional vcores are put into state VCORE_PIGGYBACK and their runnable VCPU threads are started as well as the original vcore, which is called the master vcore. After the vcores have exited the guest, the extra ones are put back onto the preempted list if any of their VCPUs are still runnable and not idle. This means that vcpu->arch.ptid is no longer necessarily the same as the physical thread that the vcpu runs on. In order to make it easier for code that wants to send an IPI to know which CPU to target, we now store that in a new field in struct vcpu_arch, called thread_cpu. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Tested-by: Laurent Vivier <lvivier@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-06-07powerpc/kernel: Rename PACA_DSCR to PACA_DSCR_DEFAULTAnshuman Khandual1-1/+1
PACA_DSCR offset macro tracks dscr_default element in the paca structure. Better change the name of this macro to match that of the data element it tracks. Makes the code more readable. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-04-21KVM: PPC: Book3S HV: Use msgsnd for signalling threads on POWER8Paul Mackerras1-3/+19
This uses msgsnd where possible for signalling other threads within the same core on POWER8 systems, rather than IPIs through the XICS interrupt controller. This includes waking secondary threads to run the guest, the interrupts generated by the virtual XICS, and the interrupts to bring the other threads out of the guest when exiting. Aggregated statistics from debugfs across vcpus for a guest with 32 vcpus, 8 threads/vcore, running on a POWER8, show this before the change: rm_entry: 3387.6ns (228 - 86600, 1008969 samples) rm_exit: 4561.5ns (12 - 3477452, 1009402 samples) rm_intr: 1660.0ns (12 - 553050, 3600051 samples) and this after the change: rm_entry: 3060.1ns (212 - 65138, 953873 samples) rm_exit: 4244.1ns (12 - 9693408, 954331 samples) rm_intr: 1342.3ns (12 - 1104718, 3405326 samples) for a test of booting Fedora 20 big-endian to the login prompt. The time taken for a H_PROD hcall (which is handled in the host kernel) went down from about 35 microseconds to about 16 microseconds with this change. The noinline added to kvmppc_run_core turned out to be necessary for good performance, at least with gcc 4.9.2 as packaged with Fedora 21 and a little-endian POWER8 host. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Translate kvmhv_commence_exit to CPaul Mackerras1-58/+8
This replaces the assembler code for kvmhv_commence_exit() with C code in book3s_hv_builtin.c. It also moves the IPI sending code that was in book3s_hv_rm_xics.c into a new kvmhv_rm_send_ipi() function so it can be used by kvmhv_commence_exit() as well as icp_rm_set_vcpu_irq(). Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Streamline guest entry and exitPaul Mackerras1-86/+126
On entry to the guest, secondary threads now wait for the primary to switch the MMU after loading up most of their state, rather than before. This means that the secondary threads get into the guest sooner, in the common case where the secondary threads get to kvmppc_hv_entry before the primary thread. On exit, the first thread out increments the exit count and interrupts the other threads (to get them out of the guest) before saving most of its state, rather than after. That means that the other threads exit sooner and means that the first thread doesn't spend so much time waiting for the other threads at the point where the MMU gets switched back to the host. This pulls out the code that increments the exit count and interrupts other threads into a separate function, kvmhv_commence_exit(). This also makes sure that r12 and vcpu->arch.trap are set correctly in some corner cases. Statistics from /sys/kernel/debug/kvm/vm*/vcpu*/timings show the improvement. Aggregating across vcpus for a guest with 32 vcpus, 8 threads/vcore, running on a POWER8, gives this before the change: rm_entry: avg 4537.3ns (222 - 48444, 1068878 samples) rm_exit: avg 4787.6ns (152 - 165490, 1010717 samples) rm_intr: avg 1673.6ns (12 - 341304, 3818691 samples) and this after the change: rm_entry: avg 3427.7ns (232 - 68150, 1118921 samples) rm_exit: avg 4716.0ns (12 - 150720, 1119477 samples) rm_intr: avg 1614.8ns (12 - 522436, 3850432 samples) showing a substantial reduction in the time spent per guest entry in the real-mode guest entry code, and smaller reductions in the real mode guest exit and interrupt handling times. (The test was to start the guest and boot Fedora 20 big-endian to the login prompt.) Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Use bitmap of active threads rather than countPaul Mackerras1-33/+28
Currently, the entry_exit_count field in the kvmppc_vcore struct contains two 8-bit counts, one of the threads that have started entering the guest, and one of the threads that have started exiting the guest. This changes it to an entry_exit_map field which contains two bitmaps of 8 bits each. The advantage of doing this is that it gives us a bitmap of which threads need to be signalled when exiting the guest. That means that we no longer need to use the trick of setting the HDEC to 0 to pull the other threads out of the guest, which led in some cases to a spurious HDEC interrupt on the next guest entry. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Use decrementer to wake napping threadsPaul Mackerras1-2/+41
This arranges for threads that are napping due to their vcpu having ceded or due to not having a vcpu to wake up at the end of the guest's timeslice without having to be poked with an IPI. We do that by arranging for the decrementer to contain a value no greater than the number of timebase ticks remaining until the end of the timeslice. In the case of a thread with no vcpu, this number is in the hypervisor decrementer already. In the case of a ceded vcpu, we use the smaller of the HDEC value and the DEC value. Using the DEC like this when ceded means we need to save and restore the guest decrementer value around the nap. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Don't wake thread with no vcpu on guest IPIPaul Mackerras1-3/+7
When running a multi-threaded guest and vcpu 0 in a virtual core is not running in the guest (i.e. it is busy elsewhere in the host), thread 0 of the physical core will switch the MMU to the guest and then go to nap mode in the code at kvm_do_nap. If the guest sends an IPI to thread 0 using the msgsndp instruction, that will wake up thread 0 and cause all the threads in the guest to exit to the host unnecessarily. To avoid the unnecessary exit, this arranges for the PECEDP bit to be cleared in this situation. When napping due to a H_CEDE from the guest, we still set PECEDP so that the thread will wake up on an IPI sent using msgsndp. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Get rid of vcore nap_count and n_wokenPaul Mackerras1-12/+7
We can tell when a secondary thread has finished running a guest by the fact that it clears its kvm_hstate.kvm_vcpu pointer, so there is no real need for the nap_count field in the kvmppc_vcore struct. This changes kvmppc_wait_for_nap to poll the kvm_hstate.kvm_vcpu pointers of the secondary threads rather than polling vc->nap_count. Besides reducing the size of the kvmppc_vcore struct by 8 bytes, this also means that we can tell which secondary threads have got stuck and thus print a more informative error message. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Minor cleanupsPaul Mackerras1-25/+19
* Remove unused kvmppc_vcore::n_busy field. * Remove setting of RMOR, since it was only used on PPC970 and the PPC970 KVM support has been removed. * Don't use r1 or r2 in setting the runlatch since they are conventionally reserved for other things; use r0 instead. * Streamline the code a little and remove the ext_interrupt_to_host label. * Add some comments about register usage. * hcall_try_real_mode doesn't need to be global, and can't be called from C code anyway. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Accumulate timing information for real-mode codePaul Mackerras1-2/+139
This reads the timebase at various points in the real-mode guest entry/exit code and uses that to accumulate total, minimum and maximum time spent in those parts of the code. Currently these times are accumulated per vcpu in 5 parts of the code: * rm_entry - time taken from the start of kvmppc_hv_entry() until just before entering the guest. * rm_intr - time from when we take a hypervisor interrupt in the guest until we either re-enter the guest or decide to exit to the host. This includes time spent handling hcalls in real mode. * rm_exit - time from when we decide to exit the guest until the return from kvmppc_hv_entry(). * guest - time spend in the guest * cede - time spent napping in real mode due to an H_CEDE hcall while other threads in the same vcore are active. These times are exposed in debugfs in a directory per vcpu that contains a file called "timings". This file contains one line for each of the 5 timings above, with the name followed by a colon and 4 numbers, which are the count (number of times the code has been executed), the total time, the minimum time, and the maximum time, all in nanoseconds. The overhead of the extra code amounts to about 30ns for an hcall that is handled in real mode (e.g. H_SET_DABR), which is about 25%. Since production environments may not wish to incur this overhead, the new code is conditional on a new config symbol, CONFIG_KVM_BOOK3S_HV_EXIT_TIMING. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-04-21KVM: PPC: Book3S HV: Add fast real-mode H_RANDOM implementation.Michael Ellerman1-0/+115
Some PowerNV systems include a hardware random-number generator. This HWRNG is present on POWER7+ and POWER8 chips and is capable of generating one 64-bit random number every microsecond. The random numbers are produced by sampling a set of 64 unstable high-frequency oscillators and are almost completely entropic. PAPR defines an H_RANDOM hypercall which guests can use to obtain one 64-bit random sample from the HWRNG. This adds a real-mode implementation of the H_RANDOM hypercall. This hypercall was implemented in real mode because the latency of reading the HWRNG is generally small compared to the latency of a guest exit and entry for all the threads in the same virtual core. Userspace can detect the presence of the HWRNG and the H_RANDOM implementation by querying the KVM_CAP_PPC_HWRNG capability. The H_RANDOM hypercall implementation will only be invoked when the guest does an H_RANDOM hypercall if userspace first enables the in-kernel H_RANDOM implementation using the KVM_CAP_PPC_ENABLE_HCALL capability. Signed-off-by: Michael Ellerman <michael@ellerman.id.au> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2015-03-20KVM: PPC: Book3S HV: Fix instruction emulationPaul Mackerras1-0/+1
Commit 4a157d61b48c ("KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register") had the side effect that we no longer reset vcpu->arch.last_inst to -1 on guest exit in the cases where the instruction is not fetched from the guest. This means that if instruction emulation turns out to be required in those cases, the host will emulate the wrong instruction, since vcpu->arch.last_inst will contain the last instruction that was emulated. This fixes it by making sure that vcpu->arch.last_inst is reset to -1 in those cases. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-29powerpc/kvm: Create proper names for the kvm_host_state PMU fieldsMichael Ellerman1-14/+14
We have two arrays in kvm_host_state that contain register values for the PMU. Currently we only create an asm-offsets symbol for the base of the arrays, and do the array offset in the assembly code. Creating an asm-offsets symbol for each field individually makes the code much nicer to read, particularly for the MMCRx/SIxR/SDAR fields, and might have helped us notice the recent double restore bug we had in this code. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Alexander Graf <agraf@suse.de>
2014-12-18Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-243/+8
Pull KVM update from Paolo Bonzini: "3.19 changes for KVM: - spring cleaning: removed support for IA64, and for hardware- assisted virtualization on the PPC970 - ARM, PPC, s390 all had only small fixes For x86: - small performance improvements (though only on weird guests) - usual round of hardware-compliancy fixes from Nadav - APICv fixes - XSAVES support for hosts and guests. XSAVES hosts were broken because the (non-KVM) XSAVES patches inadvertently changed the KVM userspace ABI whenever XSAVES was enabled; hence, this part is going to stable. Guest support is just a matter of exposing the feature and CPUID leaves support" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits) KVM: move APIC types to arch/x86/ KVM: PPC: Book3S: Enable in-kernel XICS emulation by default KVM: PPC: Book3S HV: Improve H_CONFER implementation KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register KVM: PPC: Book3S HV: Remove code for PPC970 processors KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions KVM: PPC: Book3S HV: Simplify locking around stolen time calculations arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function arch: powerpc: kvm: book3s_pr.c: Remove unused function arch: powerpc: kvm: book3s.c: Remove some unused functions arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked KVM: PPC: Book3S HV: ptes are big endian KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI KVM: PPC: Book3S HV: Fix KSM memory corruption KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI KVM: PPC: Book3S HV: Fix computation of tlbie operand KVM: PPC: Book3S HV: Add missing HPTE unlock KVM: PPC: BookE: Improve irq inject tracepoint arm/arm64: KVM: Require in-kernel vgic for the arch timers ...
2014-12-17KVM: PPC: Book3S HV: Improve H_CONFER implementationSam Bobroff1-1/+1
Currently the H_CONFER hcall is implemented in kernel virtual mode, meaning that whenever a guest thread does an H_CONFER, all the threads in that virtual core have to exit the guest. This is bad for performance because it interrupts the other threads even if they are doing useful work. The H_CONFER hcall is called by a guest VCPU when it is spinning on a spinlock and it detects that the spinlock is held by a guest VCPU that is currently not running on a physical CPU. The idea is to give this VCPU's time slice to the holder VCPU so that it can make progress towards releasing the lock. To avoid having the other threads exit the guest unnecessarily, we add a real-mode implementation of H_CONFER that checks whether the other threads are doing anything. If all the other threads are idle (i.e. in H_CEDE) or trying to confer (i.e. in H_CONFER), it returns H_TOO_HARD which causes a guest exit and allows the H_CONFER to be handled in virtual mode. Otherwise it spins for a short time (up to 10 microseconds) to give other threads the chance to observe that this thread is trying to confer. The spin loop also terminates when any thread exits the guest or when all other threads are idle or trying to confer. If the timeout is reached, the H_CONFER returns H_SUCCESS. In this case the guest VCPU will recheck the spinlock word and most likely call H_CONFER again. This also improves the implementation of the H_CONFER virtual mode handler. If the VCPU is part of a virtual core (vcore) which is runnable, there will be a 'runner' VCPU which has taken responsibility for running the vcore. In this case we yield to the runner VCPU rather than the target VCPU. We also introduce a check on the target VCPU's yield count: if it differs from the yield count passed to H_CONFER, the target VCPU has run since H_CONFER was called and may have already released the lock. This check is required by PAPR. Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR registerPaul Mackerras1-2/+2
There are two ways in which a guest instruction can be obtained from the guest in the guest exit code in book3s_hv_rmhandlers.S. If the exit was caused by a Hypervisor Emulation interrupt (i.e. an illegal instruction), the offending instruction is in the HEIR register (Hypervisor Emulation Instruction Register). If the exit was caused by a load or store to an emulated MMIO device, we load the instruction from the guest by turning data relocation on and loading the instruction with an lwz instruction. Unfortunately, in the case where the guest has opposite endianness to the host, these two methods give results of different endianness, but both get put into vcpu->arch.last_inst. The HEIR value has been loaded using guest endianness, whereas the lwz will load the instruction using host endianness. The rest of the code that uses vcpu->arch.last_inst assumes it was loaded using host endianness. To fix this, we define a new vcpu field to store the HEIR value. Then, in kvmppc_handle_exit_hv(), we transfer the value from this new field to vcpu->arch.last_inst, doing a byte-swap if the guest and host endianness differ. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-17KVM: PPC: Book3S HV: Remove code for PPC970 processorsPaul Mackerras1-240/+5
This removes the code that was added to enable HV KVM to work on PPC970 processors. The PPC970 is an old CPU that doesn't support virtualizing guest memory. Removing PPC970 support also lets us remove the code for allocating and managing contiguous real-mode areas, the code for the !kvm->arch.using_mmu_notifiers case, the code for pinning pages of guest memory when first accessed and keeping track of which pages have been pinned, and the code for handling H_ENTER hypercalls in virtual mode. Book3S HV KVM is now supported only on POWER7 and POWER8 processors. The KVM_CAP_PPC_RMA capability now always returns 0. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-12-08powerpc/powernv: Return to cpu offline loop when finished in KVM guestPaul Mackerras1-17/+37
When a secondary hardware thread has finished running a KVM guest, we currently put that thread into nap mode using a nap instruction in the KVM code. This changes the code so that instead of doing a nap instruction directly, we instead cause the call to power7_nap() that put the thread into nap mode to return. The reason for doing this is to avoid having the KVM code having to know what low-power mode to put the thread into. In the case of a secondary thread used to run a KVM guest, the thread will be offline from the point of view of the host kernel, and the relevant power7_nap() call is the one in pnv_smp_cpu_disable(). In this case we don't want to clear pending IPIs in the offline loop in that function, since that might cause us to miss the wakeup for the next time the thread needs to run a guest. To tell whether or not to clear the interrupt, we use the SRR1 value returned from power7_nap(), and check if it indicates an external interrupt. We arrange that the return from power7_nap() when we have finished running a guest returns 0, so pending interrupts don't get flushed in that case. Note that it is important a secondary thread that has finished executing in the guest, or that didn't have a guest to run, should not return to power7_nap's caller while the kvm_hstate.hwthread_req flag in the PACA is non-zero, because the return from power7_nap will reenable the MMU, and the MMU might still be in guest context. In this situation we spin at low priority in real mode waiting for hwthread_req to become zero. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-22KVM: PPC: Book3S HV: Add register name when loading tocMichael Neuling1-1/+2
Add 'r' to register name r2 in kvmppc_hv_enter. Also update comment at the top of kvmppc_hv_enter to indicate that R2/TOC is non-volatile. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-08-07Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-24/+46
Pull second round of KVM changes from Paolo Bonzini: "Here are the PPC and ARM changes for KVM, which I separated because they had small conflicts (respectively within KVM documentation, and with 3.16-rc changes). Since they were all within the subsystem, I took care of them. Stephen Rothwell reported some snags in PPC builds, but they are all fixed now; the latest linux-next report was clean. New features for ARM include: - KVM VGIC v2 emulation on GICv3 hardware - Big-Endian support for arm/arm64 (guest and host) - Debug Architecture support for arm64 (arm32 is on Christoffer's todo list) And for PPC: - Book3S: Good number of LE host fixes, enable HV on LE - Book3S HV: Add in-guest debug support This release drops support for KVM on the PPC440. As a result, the PPC merge removes more lines than it adds. :) I also included an x86 change, since Davidlohr tied it to an independent bug report and the reporter quickly provided a Tested-by; there was no reason to wait for -rc2" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (122 commits) KVM: Move more code under CONFIG_HAVE_KVM_IRQFD KVM: nVMX: fix "acknowledge interrupt on exit" when APICv is in use KVM: nVMX: Fix nested vmexit ack intr before load vmcs01 KVM: PPC: Enable IRQFD support for the XICS interrupt controller KVM: Give IRQFD its own separate enabling Kconfig option KVM: Move irq notifier implementation into eventfd.c KVM: Move all accesses to kvm::irq_routing into irqchip.c KVM: irqchip: Provide and use accessors for irq routing table KVM: Don't keep reference to irq routing table in irqfd struct KVM: PPC: drop duplicate tracepoint arm64: KVM: fix 64bit CP15 VM access for 32bit guests KVM: arm64: GICv3: mandate page-aligned GICV region arm64: KVM: GICv3: move system register access to msr_s/mrs_s KVM: PPC: PR: Handle FSCR feature deselects KVM: PPC: HV: Remove generic instruction emulation KVM: PPC: BOOKEHV: rename e500hv_spr to bookehv_spr KVM: PPC: Remove DCR handling KVM: PPC: Expose helper functions for data/inst faults KVM: PPC: Separate loadstore emulation from priv emulation KVM: PPC: Handle magic page in kvmppc_ld/st ...
2014-08-07Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpcLinus Torvalds1-0/+6
Pull powerpc updates from Ben Herrenschmidt: "This is the powerpc new goodies for 3.17. The short story: The biggest bit is Michael removing all of pre-POWER4 processor support from the 64-bit kernel. POWER3 and rs64. This gets rid of a ton of old cruft that has been bitrotting in a long while. It was broken for quite a few versions already and nobody noticed. Nobody uses those machines anymore. While at it, he cleaned up a bunch of old dusty cabinets, getting rid of a skeletton or two. Then, we have some base VFIO support for KVM, which allows assigning of PCI devices to KVM guests, support for large 64-bit BARs on "powernv" platforms, support for HMI (Hardware Management Interrupts) on those same platforms, some sparse-vmemmap improvements (for memory hotplug), There is the usual batch of Freescale embedded updates (summary in the merge commit) and fixes here or there, I think that's it for the highlights" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (102 commits) powerpc/eeh: Export eeh_iommu_group_to_pe() powerpc/eeh: Add missing #ifdef CONFIG_IOMMU_API powerpc: Reduce scariness of interrupt frames in stack traces powerpc: start loop at section start of start in vmemmap_populated() powerpc: implement vmemmap_free() powerpc: implement vmemmap_remove_mapping() for BOOK3S powerpc: implement vmemmap_list_free() powerpc: Fail remap_4k_pfn() if PFN doesn't fit inside PTE powerpc/book3s: Fix endianess issue for HMI handling on napping cpus. powerpc/book3s: handle HMIs for cpus in nap mode. powerpc/powernv: Invoke opal call to handle hmi. powerpc/book3s: Add basic infrastructure to handle HMI in Linux. powerpc/iommu: Fix comments with it_page_shift powerpc/powernv: Handle compound PE in config accessors powerpc/powernv: Handle compound PE for EEH powerpc/powernv: Handle compound PE powerpc/powernv: Split ioda_eeh_get_state() powerpc/powernv: Allow to freeze PE powerpc/powernv: Enable M64 aperatus for PHB3 powerpc/eeh: Aux PE data for error log ...
2014-08-05powerpc/book3s: Add basic infrastructure to handle HMI in Linux.Mahesh Salgaonkar1-0/+6
Handle Hypervisor Maintenance Interrupt (HMI) in Linux. This patch implements basic infrastructure to handle HMI in Linux host. The design is to invoke opal handle hmi in real mode for recovery and set irq_pending when we hit HMI. During check_irq_replay pull opal hmi event and print hmi info on console. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-07-28KVM: PPC: Book3S HV: Fix ABIv2 on LEAlexander Graf1-8/+8
For code that doesn't live in modules we can just branch to the real function names, giving us compatibility with ABIv1 and ABIv2. Do this for the compiled-in code of HV KVM. Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28KVM: PPC: Book3S HV: Access XICS in BEAlexander Graf1-4/+14
On the exit path from the guest we check what type of interrupt we received if we received one. This means we're doing hardware access to the XICS interrupt controller. However, when running on a little endian system, this access is byte reversed. So let's make sure to swizzle the bytes back again and virtually make XICS accesses big endian. Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28KVM: PPC: Book3S HV: Access host lppaca and shadow slb in BEAlexander Graf1-10/+10
Some data structures are always stored in big endian. Among those are the LPPACA fields as well as the shadow slb. These structures might be shared with a hypervisor. So whenever we access those fields, make sure we do so in big endian byte order. Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28KVM: PPC: Book3S: Allow only implemented hcalls to be enabled or disabledPaul Mackerras1-0/+1
This adds code to check that when the KVM_CAP_PPC_ENABLE_HCALL capability is used to enable or disable in-kernel handling of an hcall, that the hcall is actually implemented by the kernel. If not an EINVAL error is returned. This also checks the default-enabled list of hcalls and prints a warning if any hcall there is not actually implemented. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28KVM: PPC: Book3S: Controls for in-kernel sPAPR hypercall handlingPaul Mackerras1-0/+11
This provides a way for userspace controls which sPAPR hcalls get handled in the kernel. Each hcall can be individually enabled or disabled for in-kernel handling, except for H_RTAS. The exception for H_RTAS is because userspace can already control whether individual RTAS functions are handled in-kernel or not via the KVM_PPC_RTAS_DEFINE_TOKEN ioctl, and because the numeric value for H_RTAS is out of the normal sequence of hcall numbers. Hcalls are enabled or disabled using the KVM_ENABLE_CAP ioctl for the KVM_CAP_PPC_ENABLE_HCALL capability on the file descriptor for the VM. The args field of the struct kvm_enable_cap specifies the hcall number in args[0] and the enable/disable flag in args[1]; 0 means disable in-kernel handling (so that the hcall will always cause an exit to userspace) and 1 means enable. Enabling or disabling in-kernel handling of an hcall is effective across the whole VM. The ability for KVM_ENABLE_CAP to be used on a VM file descriptor on PowerPC is new, added by this commit. The KVM_CAP_ENABLE_CAP_VM capability advertises that this ability exists. When a VM is created, an initial set of hcalls are enabled for in-kernel handling. The set that is enabled is the set that have an in-kernel implementation at this point. Any new hcall implementations from this point onwards should not be added to the default set without a good reason. No distinction is made between real-mode and virtual-mode hcall implementations; the one setting controls them both. Signed-off-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28KVM: PPC: Assembly functions exported to modules need _GLOBAL_TOC()Anton Blanchard1-1/+1
Both kvmppc_hv_entry_trampoline and kvmppc_entry_trampoline are assembly functions that are exported to modules and also require a valid r2. As such we need to use _GLOBAL_TOC so we provide a global entry point that establishes the TOC (r2). Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-28KVM: PPC: Book3S HV: Fix ABIv2 indirect branch issueAnton Blanchard1-2/+2
To establish addressability quickly, ABIv2 requires the target address of the function being called to be in r12. Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-07-08Merge tag 'signed-for-3.16' of git://github.com/agraf/linux-2.6 into kvm-masterPaolo Bonzini1-1/+1
Patch queue for 3.16 - 2014-07-08 A few bug fixes to make 3.16 work well with KVM on PowerPC: - Fix ppc32 module builds - Fix Little Endian hosts - Fix Book3S HV HPTE lookup with huge pages in guest - Fix BookE lock leak
2014-07-07KVM: PPC: Assembly functions exported to modules need _GLOBAL_TOC()Anton Blanchard1-1/+1
Both kvmppc_hv_entry_trampoline and kvmppc_entry_trampoline are assembly functions that are exported to modules and also require a valid r2. As such we need to use _GLOBAL_TOC so we provide a global entry point that establishes the TOC (r2). Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Alexander Graf <agraf@suse.de>
2014-06-11powerpc/book3s: Fix guest MC delivery mechanism to avoid soft lockups in guest.Mahesh Salgaonkar1-3/+16
Currently we forward MCEs to guest which have been recovered by guest. And for unhandled errors we do not deliver the MCE to guest. It looks like with no support of FWNMI in qemu, guest just panics whenever we deliver the recovered MCEs to guest. Also, the existig code used to return to host for unhandled errors which was casuing guest to hang with soft lockups inside guest and makes it difficult to recover guest instance. This patch now forwards all fatal MCEs to guest causing guest to crash/panic. And, for recovered errors we just go back to normal functioning of guest instead of returning to host. This fixes soft lockup issues in guest. This patch also fixes an issue where guest MCE events were not logged to host console. Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>