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2015-07-29KVM: s390: propagate error from enable storage keyDominik Dingel1-1/+3
As enabling storage keys might fail, we should forward the error. Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-07-27atomic: Replace atomic_{set,clear}_mask() usagePeter Zijlstra1-16/+16
Replace the deprecated atomic_{set,clear}_mask() usage with the now ubiquous atomic_{or,andnot}() functions. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-22s390/kernel: lazy restore fpu registersHendrik Brueckner1-37/+95
Improve the save and restore behavior of FPU register contents to use the vector extension within the kernel. The kernel does not use floating-point or vector registers and, therefore, saving and restoring the FPU register contents are performed for handling signals or switching processes only. To prepare for using vector instructions and vector registers within the kernel, enhance the save behavior and implement a lazy restore at return to user space from a system call or interrupt. To implement the lazy restore, the save_fpu_regs() sets a CPU information flag, CIF_FPU, to indicate that the FPU registers must be restored. Saving and setting CIF_FPU is performed in an atomic fashion to be interrupt-safe. When the kernel wants to use the vector extension or wants to change the FPU register state for a task during signal handling, the save_fpu_regs() must be called first. The CIF_FPU flag is also set at process switch. At return to user space, the FPU state is restored. In particular, the FPU state includes the floating-point or vector register contents, as well as, vector-enablement and floating-point control. The FPU state restore and clearing CIF_FPU is also performed in an atomic fashion. For KVM, the restore of the FPU register state is performed when restoring the general-purpose guest registers before the SIE instructions is started. Because the path towards the SIE instruction is interruptible, the CIF_FPU flag must be checked again right before going into SIE. If set, the guest registers must be reloaded again by re-entering the outer SIE loop. This is the same behavior as if the SIE critical section is interrupted. Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-07-22s390/kvm: validate the floating-point control before restoring itHendrik Brueckner1-2/+8
The kvm_arch_vcpu_load() does not validate whether the floating-point control (FPC) is valid. Further, the return code of the restore is not checked too. If the FPC is invalid, the restore fails and the host FPC value might remain. The correct behavior would be to clear the FPC if it is not valid. Hence, validate the FPC value and, optionally, reset the value before restoring it. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-06-24Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-28/+53
Pull first batch of KVM updates from Paolo Bonzini: "The bulk of the changes here is for x86. And for once it's not for silicon that no one owns: these are really new features for everyone. Details: - ARM: several features are in progress but missed the 4.2 deadline. So here is just a smattering of bug fixes, plus enabling the VFIO integration. - s390: Some fixes/refactorings/optimizations, plus support for 2GB pages. - x86: * host and guest support for marking kvmclock as a stable scheduler clock. * support for write combining. * support for system management mode, needed for secure boot in guests. * a bunch of cleanups required for the above * support for virtualized performance counters on AMD * legacy PCI device assignment is deprecated and defaults to "n" in Kconfig; VFIO replaces it On top of this there are also bug fixes and eager FPU context loading for FPU-heavy guests. - Common code: Support for multiple address spaces; for now it is used only for x86 SMM but the s390 folks also have plans" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits) KVM: s390: clear floating interrupt bitmap and parameters KVM: x86/vPMU: Enable PMU handling for AMD PERFCTRn and EVNTSELn MSRs KVM: x86/vPMU: Implement AMD vPMU code for KVM KVM: x86/vPMU: Define kvm_pmu_ops to support vPMU function dispatch KVM: x86/vPMU: introduce kvm_pmu_msr_idx_to_pmc KVM: x86/vPMU: reorder PMU functions KVM: x86/vPMU: whitespace and stylistic adjustments in PMU code KVM: x86/vPMU: use the new macros to go between PMC, PMU and VCPU KVM: x86/vPMU: introduce pmu.h header KVM: x86/vPMU: rename a few PMU functions KVM: MTRR: do not map huge page for non-consistent range KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type KVM: MTRR: introduce mtrr_for_each_mem_type KVM: MTRR: introduce fixed_mtrr_addr_* functions KVM: MTRR: sort variable MTRRs KVM: MTRR: introduce var_mtrr_range KVM: MTRR: introduce fixed_mtrr_segment table KVM: MTRR: improve kvm_mtrr_get_guest_memory_type KVM: MTRR: do not split 64 bits MSR content KVM: MTRR: clean up mtrr default type ...
2015-06-03Merge tag 'kvm-s390-next-20150602' of ↵Paolo Bonzini1-3/+8
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next KVM: s390: Fix and cleanup for 4.2 (kvm/next) One small fix for a commit targetted for 4.2 and one cleanup regarding our printks.
2015-06-02KVM: s390: introduce KMSG_COMPONENT for kvm-s390David Hildenbrand1-2/+6
Let's remove "kvm-s390" from our printk messages and make use of pr_fmt instead. Also replace one printk() occurrence by a equivalent pr_warn on the way. Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-06-02KVM: s390: call exit_sie() directly on vcpu block/requestDavid Hildenbrand1-1/+2
Thinking about it, I can't find a real use case where we want to block a VCPU and not kick it out of SIE. (except if we want to do the same in batch for multiple VCPUs - but that's a micro optimization) So let's simply perform the exit_sie() calls directly when setting the other magic block bits in the SIE. Otherwise e.g. kvm_s390_set_tod_low() still has other VCPUs running after that call, working with a wrong epoch. Fixes: 27406cd50c ("KVM: s390: provide functions for blocking all CPUs") Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-28KVM: add "new" argument to kvm_arch_commit_memory_regionPaolo Bonzini1-0/+1
This lets the function access the new memory slot without going through kvm_memslots and id_to_memslot. It will simplify the code when more than one address space will be supported. Unfortunately, the "const"ness of the new argument must be casted away in two places. Fixing KVM to accept const struct kvm_memory_slot pointers would require modifications in pretty much all architectures, and is left for later. Reviewed-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26KVM: const-ify uses of struct kvm_userspace_memory_regionPaolo Bonzini1-2/+2
Architecture-specific helpers are not supposed to muck with struct kvm_userspace_memory_region contents. Add const to enforce this. In order to eliminate the only write in __kvm_set_memory_region, the cleaning of deleted slots is pulled up from update_memslots to __kvm_set_memory_region. Reviewed-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Reviewed-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-26KVM: use kvm_memslots whenever possiblePaolo Bonzini1-1/+3
kvm_memslots provides lockdep checking. Use it consistently instead of explicit dereferencing of kvm->memslots. Reviewed-by: Radim Krcmar <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-05-13s390/sclp: unify basic sclp access by exposing "struct sclp"David Hildenbrand1-4/+4
Let's unify basic access to sclp fields by storing the data in an external struct in asm/sclp.h. The values can now directly be accessed by other components, so there is no need for most accessor functions and external variables anymore. The mtid, mtid_max and facility part will be cleaned up separately. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-05-11Merge tag 'kvm-s390-next-20150508' of ↵Paolo Bonzini1-18/+33
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Fixes and features for 4.2 (kvm/next) Mostly a bunch of fixes, reworks and optimizations for s390. There is one new feature (EDAT-2 inside the guest), which boils down to 2GB pages.
2015-05-08KVM: s390: provide functions for blocking all CPUsChristian Borntraeger1-5/+5
Some updates to the control blocks need to be done in a way that ensures that no CPU is within SIE. Provide wrappers around the s390_vcpu_block functions and adopt the TOD migration code to update in a guaranteed fashion. Also rename these functions to have the kvm_s390_ prefix as everything else. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
2015-05-08KVM: s390: make exit_sie_sync more robustChristian Borntraeger1-10/+18
exit_sie_sync is used to kick CPUs out of SIE and prevent reentering at any point in time. This is used to reload the prefix pages and to set the IBS stuff in a way that guarantees that after this function returns we are no longer in SIE. All current users trigger KVM requests. The request must be set before we block the CPUs to avoid races. Let's make this implicit by adding the request into a new function kvm_s390_sync_requests that replaces exit_sie_sync and split out s390_vcpu_block and s390_vcpu_unblock, that can be used to keep CPUs out of SIE independent of requests. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-05-08KVM: s390: Enable guest EDAT2 supportGuenther Hutzl1-2/+4
1. Enable EDAT2 in the list of KVM facilities 2. Handle 2G frames in pfmf instruction If we support EDAT2, we may enable handling of 2G frames if not in 24 bit mode. 3. Enable EDAT2 in sie_block If the EDAT2 facility is available we enable GED2 mode control in the sie_block. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08KVM: s390: make EDAT1 depend on host supportGuenther Hutzl1-2/+5
We should only enable EDAT1 for the guest if the host actually supports it and the cpu model for the guest has EDAT-1 enabled. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Guenther Hutzl <hutzl@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-08KVM: s390: optimize round trip time in request handlingChristian Borntraeger1-0/+2
The fast path for a sie exit is that no kvm reqest is pending. Make an early check to skip all single bit checks. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-05-07KVM: provide irq_unsafe kvm_guest_{enter|exit}Christian Borntraeger1-4/+6
Several kvm architectures disable interrupts before kvm_guest_enter. kvm_guest_enter then uses local_irq_save/restore to disable interrupts again or for the first time. Lets provide underscore versions of kvm_guest_{enter|exit} that assume being called locked. kvm_guest_enter now disables interrupts for the full function and thus we can remove the check for preemptible. This patch then adopts s390/kvm to use local_irq_disable/enable calls which are slighty cheaper that local_irq_save/restore and call these new functions. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-15KVM: s390: disable RRBM againChristian Borntraeger1-1/+1
commit b273921356df ("KVM: s390: enable more features that need no hypervisor changes") also enabled RRBM. Turns out that this instruction does need some KVM code, so lets disable that bit again. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Fixes: b273921356df ("KVM: s390: enable more features that need no hypervisor changes") Message-Id: <1429093624-49611-2-git-send-email-borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-04-13Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds1-31/+367
Pull KVM updates from Paolo Bonzini: "First batch of KVM changes for 4.1 The most interesting bit here is irqfd/ioeventfd support for ARM and ARM64. Summary: ARM/ARM64: fixes for live migration, irqfd and ioeventfd support (enabling vhost, too), page aging s390: interrupt handling rework, allowing to inject all local interrupts via new ioctl and to get/set the full local irq state for migration and introspection. New ioctls to access memory by virtual address, and to get/set the guest storage keys. SIMD support. MIPS: FPU and MIPS SIMD Architecture (MSA) support. Includes some patches from Ralf Baechle's MIPS tree. x86: bugfixes (notably for pvclock, the others are small) and cleanups. Another small latency improvement for the TSC deadline timer" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits) KVM: use slowpath for cross page cached accesses kvm: mmu: lazy collapse small sptes into large sptes KVM: x86: Clear CR2 on VCPU reset KVM: x86: DR0-DR3 are not clear on reset KVM: x86: BSP in MSR_IA32_APICBASE is writable KVM: x86: simplify kvm_apic_map KVM: x86: avoid logical_map when it is invalid KVM: x86: fix mixed APIC mode broadcast KVM: x86: use MDA for interrupt matching kvm/ppc/mpic: drop unused IRQ_testbit KVM: nVMX: remove unnecessary double caching of MAXPHYADDR KVM: nVMX: checks for address bits beyond MAXPHYADDR on VM-entry KVM: x86: cache maxphyaddr CPUID leaf in struct kvm_vcpu KVM: vmx: pass error code with internal error #2 x86: vdso: fix pvclock races with task migration KVM: remove kvm_read_hva and kvm_read_hva_atomic KVM: x86: optimize delivery of TSC deadline timer interrupt KVM: x86: extract blocking logic from __vcpu_run kvm: x86: fix x86 eflags fixed bit KVM: s390: migrate vcpu interrupt state ...
2015-03-31KVM: s390: migrate vcpu interrupt stateJens Freimann1-0/+36
This patch adds support to migrate vcpu interrupts. Two new vcpu ioctls are added which get/set the complete status of pending interrupts in one go. The ioctls are marked as available with the new capability KVM_CAP_S390_IRQ_STATE. We can not use a ONEREG, as the number of pending local interrupts is not constant and depends on the number of CPUs. To retrieve the interrupt state we add an ioctl KVM_S390_GET_IRQ_STATE. Its input parameter is a pointer to a struct kvm_s390_irq_state which has a buffer and length. For all currently pending interrupts, we copy a struct kvm_s390_irq into the buffer and pass it to userspace. To store interrupt state into a buffer provided by userspace, we add an ioctl KVM_S390_SET_IRQ_STATE. It passes a struct kvm_s390_irq_state into the kernel and injects all interrupts contained in the buffer. Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31KVM: s390: add ioctl to inject local interruptsJens Freimann1-0/+10
We have introduced struct kvm_s390_irq a while ago which allows to inject all kinds of interrupts as defined in the Principles of Operation. Add ioctl to inject interrupts with the extended struct kvm_s390_irq Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31KVM: s390: deliver floating interrupts in order of priorityJens Freimann1-1/+3
This patch makes interrupt handling compliant to the z/Architecture Principles of Operation with regard to interrupt priorities. Add a bitmap for pending floating interrupts. Each bit relates to a interrupt type and its list. A turned on bit indicates that a list contains items (interrupts) which need to be delivered. When delivering interrupts on a cpu we can merge the existing bitmap for cpu-local interrupts and floating interrupts and have a single mechanism for delivery. Currently we have one list for all kinds of floating interrupts and a corresponding spin lock. This patch adds a separate list per interrupt type. An exception to this are service signal and machine check interrupts, as there can be only one pending interrupt at a time. Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-31KVM: s390: enable more features that need no hypervisor changesChristian Borntraeger1-2/+2
After some review about what these facilities do, the following facilities will work under KVM and can, therefore, be reported to the guest if the cpu model and the host cpu provide this bit. There are plans underway to make the whole bit thing more readable, but its not yet finished. So here are some last bit changes and we enhance the KVM mask with: 9 The sense-running-status facility is installed in the z/Architecture architectural mode. ---> handled by SIE or KVM 10 The conditional-SSKE facility is installed in the z/Architecture architectural mode. ---> handled by SIE. KVM will retry SIE 13 The IPTE-range facility is installed in the z/Architecture architectural mode. ---> handled by SIE. KVM will retry SIE 36 The enhanced-monitor facility is installed in the z/Architecture architectural mode. ---> handled by SIE 47 The CMPSC-enhancement facility is installed in the z/Architecture architectural mode. ---> handled by SIE 48 The decimal-floating-point zoned-conversion facility is installed in the z/Architecture architectural mode. ---> handled by SIE 49 The execution-hint, load-and-trap, miscellaneous- instruction-extensions and processor-assist ---> handled by SIE 51 The local-TLB-clearing facility is installed in the z/Architecture architectural mode. ---> handled by SIE 52 The interlocked-access facility 2 is installed. ---> handled by SIE 53 The load/store-on-condition facility 2 and load-and- zero-rightmost-byte facility are installed in the z/Architecture architectural mode. ---> handled by SIE 57 The message-security-assist-extension-5 facility is installed in the z/Architecture architectural mode. ---> handled by SIE 66 The reset-reference-bits-multiple facility is installed in the z/Architecture architectural mode. ---> handled by SIE. KVM will retry SIE 80 The decimal-floating-point packed-conversion facility is installed in the z/Architecture architectural mode. ---> handled by SIE Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Tested-by: Michael Mueller <mimu@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2015-03-17KVM: s390: represent SIMD cap in kvm facilityMichael Mueller1-8/+11
The patch represents capability KVM_CAP_S390_VECTOR_REGISTERS by means of the SIMD facility bit. This allows to a) disable the use of SIMD when used in conjunction with a not-SIMD-aware QEMU, b) to enable SIMD when used with a SIMD-aware version of QEMU and c) finally by means of a QEMU version using the future cpu model ioctls. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Tested-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17KVM: s390: drop SIMD bit from kvm_s390_fac_list_maskMichael Mueller1-1/+0
Setting the SIMD bit in the KVM mask is an issue because it makes the facility visible but not usable to the guest, thus it needs to be removed again. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17KVM: s390: Create ioctl for Getting/Setting guest storage keysJason J. Herne1-0/+123
Provide the KVM_S390_GET_SKEYS and KVM_S390_SET_SKEYS ioctl which can be used to get/set guest storage keys. This functionality is needed for live migration of s390 guests that use storage keys. Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17KVM: s390: introduce post handlers for STSIEkaterina Tumanova1-0/+5
The Store System Information (STSI) instruction currently collects all information it relays to the caller in the kernel. Some information, however, is only available in user space. An example of this is the guest name: The kernel always sets "KVMGuest", but user space knows the actual guest name. This patch introduces a new exit, KVM_EXIT_S390_STSI, guarded by a capability that can be enabled by user space if it wants to be able to insert such data. User space will be provided with the target buffer and the requested STSI function code. Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17KVM: s390: Add MEMOP ioctls for reading/writing guest memoryThomas Huth1-0/+74
On s390, we've got to make sure to hold the IPTE lock while accessing logical memory. So let's add an ioctl for reading and writing logical memory to provide this feature for userspace, too. The maximum transfer size of this call is limited to 64kB to prevent that the guest can trigger huge copy_from/to_user transfers. QEMU currently only requests up to one or two pages so far, so 16*4kB seems to be a reasonable limit here. Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17KVM: s390: Guest's memory access functions get access registersAlexander Yarygin1-1/+1
In access register mode, the write_guest() read_guest() and other functions will invoke the access register translation, which requires an ar, designated by one of the instruction fields. Signed-off-by: Alexander Yarygin <yarygin@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-17KVM: s390: cleanup jump lables in kvm_arch_init_vmDominik Dingel1-9/+5
As all cleanup functions can handle their respective NULL case there is no need to have more than one error jump label. Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-11kvm: move advertising of KVM_CAP_IRQFD to common codePaolo Bonzini1-1/+0
POWER supports irqfds but forgot to advertise them. Some userspace does not check for the capability, but others check it---thus they work on x86 and s390 but not POWER. To avoid that other architectures in the future make the same mistake, let common code handle KVM_CAP_IRQFD the same way as KVM_CAP_IRQFD_RESAMPLE. Reported-and-tested-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Fixes: 297e21053a52f060944e9f0de4c64fad9bcd72fc Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2015-03-06KVM: s390: Enable vector support for capable guestEric Farman1-0/+5
We finally have all the pieces in place, so let's include the vector facility bit in the mask of available hardware facilities for the guest to recognize. Also, enable the vector functionality in the guest control blocks, to avoid a possible vector data exception that would otherwise occur when a vector instruction is issued by the guest operating system. Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06KVM: s390: Machine CheckEric Farman1-0/+29
Store additional status in the machine check handler, in order to collect status (such as vector registers) that is not defined by store status. Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06KVM: s390: Add new SIGP order to kernel countersEric Farman1-0/+1
The new SIGP order Store Additional Status at Address is totally handled by user space, but we should still record the occurrence of this order in the kernel code. Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06KVM: s390: Allocate and save/restore vector registersEric Farman1-6/+33
Define and allocate space for both the host and guest views of the vector registers for a given vcpu. The 32 vector registers occupy 128 bits each (512 bytes total), but architecturally are paired with 512 additional bytes of reserved space for future expansion. The kvm_sync_regs structs containing the registers are union'ed with 1024 bytes of padding in the common kvm_run struct. The addition of 1024 bytes of new register information clearly exceeds the existing union, so an expansion of that padding is required. When changing environments, we need to appropriately save and restore the vector registers viewed by both the host and guest, into and out of the sync_regs space. The floating point registers overlay the upper half of vector registers 0-15, so there's a bit of data duplication here that needs to be carefully avoided. Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06KVM: s390: perform vcpu model setup in a functionMichael Mueller1-6/+11
The function kvm_s390_vcpu_setup_model() now performs all cpu model realated setup tasks for a vcpu. Besides cpuid and ibc initialization, facility list assignment takes place during the setup step as well. The model setup has been pulled to the begin of vcpu setup to allow kvm facility tests. There is no need to protect the cpu model setup with a lock since the attributes can't be changed anymore as soon the first vcpu is online. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-06KVM: s390: Forward PSW to next instruction for addressing exceptionsThomas Huth1-7/+28
When the SIE exited by a DAT access exceptions which we can not resolve, the guest tried to access a page which is out of bounds and can not be paged-in. In this case we have to signal the bad access by injecting an address exception. However, address exceptions are either suppressing or terminating, i.e. the PSW has to point to the next instruction when the exception is delivered. Since the originating DAT access exception is nullifying, the PSW still points to the offending instruction instead, so we've got to forward the PSW to the next instruction. Having fixed this issue, we can now also enable the TPROT interpretation facility again which had been disabled because of this problem. Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-04KVM: s390: non-LPAR case obsolete during facilities mask initMichael Mueller1-16/+1
With patch "include guest facilities in kvm facility test" it is no longer necessary to have special handling for the non-LPAR case. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-04KVM: s390: include guest facilities in kvm facility testMichael Mueller1-14/+16
Most facility related decisions in KVM have to take into account: - the facilities offered by the underlying run container (LPAR/VM) - the facilities supported by the KVM code itself - the facilities requested by a guest VM This patch adds the KVM driver requested facilities to the test routine. It additionally renames struct s390_model_fac to kvm_s390_fac and its field names to be more meaningful. The semantics of the facilities stored in the KVM architecture structure is changed. The address arch.model.fac->list now points to the guest facility list and arch.model.fac->mask points to the KVM facility mask. This patch fixes the behaviour of KVM for some facilities for guests that ignore the guest visible facility bits, e.g. guests could use transactional memory intructions on hosts supporting them even if the chosen cpu model would not offer them. The userspace interface is not affected by this change. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-04KVM: s390: fix in memory copy of facility listsMichael Mueller1-2/+2
The facility lists were not fully copied. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-03-04KVM: s390/cpacf: Fix kernel bug under z/VMChristian Borntraeger1-3/+6
Under z/VM PQAP might trigger an operation exception if no crypto cards are defined via APVIRTUAL or APDEDICATED. [ 386.098666] Kernel BUG at 0000000000135c56 [verbose debug info unavailable] [ 386.098693] illegal operation: 0001 ilc:2 [#1] SMP [...] [ 386.098751] Krnl PSW : 0704c00180000000 0000000000135c56 (kvm_s390_apxa_installed+0x46/0x98) [...] [ 386.098804] [<000000000013627c>] kvm_arch_init_vm+0x29c/0x358 [ 386.098806] [<000000000012d008>] kvm_dev_ioctl+0xc0/0x460 [ 386.098809] [<00000000002c639a>] do_vfs_ioctl+0x332/0x508 [ 386.098811] [<00000000002c660e>] SyS_ioctl+0x9e/0xb0 [ 386.098814] [<000000000070476a>] system_call+0xd6/0x258 [ 386.098815] [<000003fffc7400a2>] 0x3fffc7400a2 Lets add an extable entry and provide a zeroed config in that case. Reported-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Thomas Huth <thuth@linux.vnet.ibm.com> Tested-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com>
2015-03-03KVM: s390/cpacf: Enable key wrapping by defaultTony Krowiak1-3/+7
z/VM and LPAR enable key wrapping by default, lets do the same on KVM. Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-02-09KVM: s390: add cpu model supportMichael Mueller1-0/+132
This patch enables cpu model support in kvm/s390 via the vm attribute interface. During KVM initialization, the host properties cpuid, IBC value and the facility list are stored in the architecture specific cpu model structure. During vcpu setup, these properties are taken to initialize the related SIE state. This mechanism allows to adjust the properties from user space and thus to implement different selectable cpu models. This patch uses the IBC functionality to block instructions that have not been implemented at the requested CPU type and GA level compared to the full host capability. Userspace has to initialize the cpu model before vcpu creation. A cpu model change of running vcpus is not possible. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-02-09KVM: s390: use facilities and cpu_id per KVMMichael Mueller1-34/+58
The patch introduces facilities and cpu_ids per virtual machine. Different virtual machines may want to expose different facilities and cpu ids to the guest, so let's make them per-vm instead of global. Signed-off-by: Michael Mueller <mimu@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-02-09KVM: s390/CPACF: Choose crypto control block formatTony Krowiak1-2/+47
We need to specify a different format for the crypto control block depending on whether the APXA facility is installed or not. Let's test for it by executing the PQAP(QCI) function and use either a format-1 or a format-2 crypto control block accordingly. This is a host only change for z13 and does not affect the guest view. Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2015-02-09KVM: s390: reenable LPP facilityChristian Borntraeger1-1/+1
commit 7be81a46695d ("KVM: s390/facilities: allow TOD-CLOCK steering facility bit") accidentially disabled the "load program parameter" facility bit during rebase for upstream submission (my fault). Re-add that bit. As this is only for a performance measurement helper instruction (used by KVM itself) cc stable is not necessary see http://www-01.ibm.com/support/docview.wss?uid=isg26fcd1cc32246f4c8852574ce0044734a (SA23-2260 The Load-Program-Parameter and CPU-Measurement Facilities) for details about LPP and its usecase. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Fixes: 7be81a46695d ("KVM: s390/facilities: allow TOD-CLOCK steering")
2015-02-06kvm: add halt_poll_ns module parameterPaolo Bonzini1-0/+1
This patch introduces a new module parameter for the KVM module; when it is present, KVM attempts a bit of polling on every HLT before scheduling itself out via kvm_vcpu_block. This parameter helps a lot for latency-bound workloads---in particular I tested it with O_DSYNC writes with a battery-backed disk in the host. In this case, writes are fast (because the data doesn't have to go all the way to the platters) but they cannot be merged by either the host or the guest. KVM's performance here is usually around 30% of bare metal, or 50% if you use cache=directsync or cache=writethrough (these parameters avoid that the guest sends pointless flush requests, and at the same time they are not slow because of the battery-backed cache). The bad performance happens because on every halt the host CPU decides to halt itself too. When the interrupt comes, the vCPU thread is then migrated to a new physical CPU, and in general the latency is horrible because the vCPU thread has to be scheduled back in. With this patch performance reaches 60-65% of bare metal and, more important, 99% of what you get if you use idle=poll in the guest. This means that the tunable gets rid of this particular bottleneck, and more work can be done to improve performance in the kernel or QEMU. Of course there is some price to pay; every time an otherwise idle vCPUs is interrupted by an interrupt, it will poll unnecessarily and thus impose a little load on the host. The above results were obtained with a mostly random value of the parameter (500000), and the load was around 1.5-2.5% CPU usage on one of the host's core for each idle guest vCPU. The patch also adds a new stat, /sys/kernel/debug/kvm/halt_successful_poll, that can be used to tune the parameter. It counts how many HLT instructions received an interrupt during the polling period; each successful poll avoids that Linux schedules the VCPU thread out and back in, and may also avoid a likely trip to C1 and back for the physical CPU. While the VM is idle, a Linux 4 VCPU VM halts around 10 times per second. Of these halts, almost all are failed polls. During the benchmark, instead, basically all halts end within the polling period, except a more or less constant stream of 50 per second coming from vCPUs that are not running the benchmark. The wasted time is thus very low. Things may be slightly different for Windows VMs, which have a ~10 ms timer tick. The effect is also visible on Marcelo's recently-introduced latency test for the TSC deadline timer. Though of course a non-RT kernel has awful latency bounds, the latency of the timer is around 8000-10000 clock cycles compared to 20000-120000 without setting halt_poll_ns. For the TSC deadline timer, thus, the effect is both a smaller average latency and a smaller variance. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-01-23KVM: s390/cpacf: Enable/disable protected key functions for kvm guestTony Krowiak1-0/+75
Created new KVM device attributes for indicating whether the AES and DES/TDES protected key functions are available for programs running on the KVM guest. The attributes are used to set up the controls in the guest SIE block that specify whether programs running on the guest will be given access to the protected key functions available on the s390 hardware. Signed-off-by: Tony Krowiak <akrowiak@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> [split MSA4/protected key into two patches]