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| * | KVM: s390: allow sync of fp registers via vregsDavid Hildenbrand2016-02-10
| |/ | | | | | | | | | | | | | | | | | | | | | | | | If we have MACHINE_HAS_VX, the floating point registers are stored in the vector register format, event if the guest isn't enabled for vector registers. So we can allow KVM_SYNC_VRS as soon as MACHINE_HAS_VX is available. This can in return be used by user space to support floating point registers via struct kvm_run when the machine has vector registers. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | Merge branch 'sched-core-for-linus' of ↵Linus Torvalds2016-03-14
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle are: - Make schedstats a runtime tunable (disabled by default) and optimize it via static keys. As most distributions enable CONFIG_SCHEDSTATS=y due to its instrumentation value, this is a nice performance enhancement. (Mel Gorman) - Implement 'simple waitqueues' (swait): these are just pure waitqueues without any of the more complex features of full-blown waitqueues (callbacks, wake flags, wake keys, etc.). Simple waitqueues have less memory overhead and are faster. Use simple waitqueues in the RCU code (in 4 different places) and for handling KVM vCPU wakeups. (Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker, Marcelo Tosatti) - sched/numa enhancements (Rik van Riel) - NOHZ performance enhancements (Rik van Riel) - Various sched/deadline enhancements (Steven Rostedt) - Various fixes (Peter Zijlstra) - ... and a number of other fixes, cleanups and smaller enhancements" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (29 commits) sched/cputime: Fix steal_account_process_tick() to always return jiffies sched/deadline: Remove dl_new from struct sched_dl_entity Revert "kbuild: Add option to turn incompatible pointer check into error" sched/deadline: Remove superfluous call to switched_to_dl() sched/debug: Fix preempt_disable_ip recording for preempt_disable() sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity time, acct: Drop irq save & restore from __acct_update_integrals() acct, time: Change indentation in __acct_update_integrals() sched, time: Remove non-power-of-two divides from __acct_update_integrals() sched/rt: Kick RT bandwidth timer immediately on start up sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug sched/debug: Move sched_domain_sysctl to debug.c sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c sched/rt: Fix PI handling vs. sched_setscheduler() sched/core: Remove duplicated sched_group_set_shares() prototype sched/fair: Consolidate nohz CPU load update code sched/fair: Avoid using decay_load_missed() with a negative value sched/deadline: Always calculate end of period on sched_yield() sched/cgroup: Fix cgroup entity load tracking tear-down rcu: Use simple wait queues where possible in rcutree ...
| * | KVM: Use simple waitqueue for vcpu->wqMarcelo Tosatti2016-02-25
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The problem: On -rt, an emulated LAPIC timer instances has the following path: 1) hard interrupt 2) ksoftirqd is scheduled 3) ksoftirqd wakes up vcpu thread 4) vcpu thread is scheduled This extra context switch introduces unnecessary latency in the LAPIC path for a KVM guest. The solution: Allow waking up vcpu thread from hardirq context, thus avoiding the need for ksoftirqd to be scheduled. Normal waitqueues make use of spinlocks, which on -RT are sleepable locks. Therefore, waking up a waitqueue waiter involves locking a sleeping lock, which is not allowed from hard interrupt context. cyclictest command line: This patch reduces the average latency in my tests from 14us to 11us. Daniel writes: Paolo asked for numbers from kvm-unit-tests/tscdeadline_latency benchmark on mainline. The test was run 1000 times on tip/sched/core 4.4.0-rc8-01134-g0905f04: ./x86-run x86/tscdeadline_latency.flat -cpu host with idle=poll. The test seems not to deliver really stable numbers though most of them are smaller. Paolo write: "Anything above ~10000 cycles means that the host went to C1 or lower---the number means more or less nothing in that case. The mean shows an improvement indeed." Before: min max mean std count 1000.000000 1000.000000 1000.000000 1000.000000 mean 5162.596000 2019270.084000 5824.491541 20681.645558 std 75.431231 622607.723969 89.575700 6492.272062 min 4466.000000 23928.000000 5537.926500 585.864966 25% 5163.000000 1613252.750000 5790.132275 16683.745433 50% 5175.000000 2281919.000000 5834.654000 23151.990026 75% 5190.000000 2382865.750000 5861.412950 24148.206168 max 5228.000000 4175158.000000 6254.827300 46481.048691 After min max mean std count 1000.000000 1000.00000 1000.000000 1000.000000 mean 5143.511000 2076886.10300 5813.312474 21207.357565 std 77.668322 610413.09583 86.541500 6331.915127 min 4427.000000 25103.00000 5529.756600 559.187707 25% 5148.000000 1691272.75000 5784.889825 17473.518244 50% 5160.000000 2308328.50000 5832.025000 23464.837068 75% 5172.000000 2393037.75000 5853.177675 24223.969976 max 5222.000000 3922458.00000 6186.720500 42520.379830 [Patch was originaly based on the swait implementation found in the -rt tree. Daniel ported it to mainline's version and gathered the benchmark numbers for tscdeadline_latency test.] Signed-off-by: Daniel Wagner <daniel.wagner@bmw-carit.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: linux-rt-users@vger.kernel.org Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/1455871601-27484-4-git-send-email-wagi@monom.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* / KVM: s390: correct fprs on SIGP (STOP AND) STORE STATUSDavid Hildenbrand2016-03-08
|/ | | | | | | | | | | | | | | | | | | | | | With MACHINE_HAS_VX, we convert the floating point registers from the vector registeres when storing the status. For other VCPUs, these are stored to vcpu->run->s.regs.vrs, but we are using current->thread.fpu.vxrs, which resolves to the currently loaded VCPU. So kvm_s390_store_status_unloaded() currently writes the wrong floating point registers (converted from the vector registers) when called from another VCPU on a z13. This is only the case for old user space not handling SIGP STORE STATUS and SIGP STOP AND STORE STATUS, but relying on the kernel implementation. All other calls come from the loaded VCPU via kvm_s390_store_status(). Fixes: 9abc2a08a7d6 (KVM: s390: fix memory overwrites when vx is disabled) Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: stable@vger.kernel.org # v4.4+ Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-01-29
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "An optimization for irq-restore, the SSM instruction is quite a bit slower than an if-statement and a STOSM. The copy_file_range system all is added. Cleanup for PCI and CIO. And a couple of bug fixes" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/cio: update measurement characteristics s390/cio: ensure consistent measurement state s390/cio: fix measurement characteristics memleak s390/zcrypt: Fix cryptographic device id in kernel messages s390/pci: remove iomap sanity checks s390/pci: set error state for unusable functions s390/pci: fix bar check s390/pci: resize iomap s390/pci: improve ZPCI_* macros s390/pci: provide ZPCI_ADDR macro s390/pci: adjust IOMAP_MAX_ENTRIES s390/numa: move numa_init_late() from device to arch_initcall s390: remove all usages of PSW_ADDR_INSN s390: remove all usages of PSW_ADDR_AMODE s390: wire up copy_file_range syscall s390: remove superfluous memblock_alloc() return value checks s390/numa: allocate memory with correct alignment s390/irqflags: optimize irq restore s390/mm: use TASK_MAX_SIZE where applicable
| * s390: remove all usages of PSW_ADDR_INSNHeiko Carstens2016-01-19
| | | | | | | | | | | | | | | | | | | | | | Yet another leftover from the 31 bit era. The usual operation "y = x & PSW_ADDR_INSN" with the PSW_ADDR_INSN mask is a nop for CONFIG_64BIT. Therefore remove all usages and hope the code is a bit less confusing. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
* | KVM: s390: fix memory overwrites when vx is disabledDavid Hildenbrand2016-01-26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kernel now always uses vector registers when available, however KVM has special logic if support is really enabled for a guest. If support is disabled, guest_fpregs.fregs will only contain memory for the fpu. The kernel, however, will store vector registers into that area, resulting in crazy memory overwrites. Simply extending that area is not enough, because the format of the registers also changes. We would have to do additional conversions, making the code even more complex. Therefore let's directly use one place for the vector/fpu registers + fpc (in kvm_run). We just have to convert the data properly when accessing it. This makes current code much easier. Please note that vector/fpu registers are now always stored to vcpu->run->s.regs.vrs. Although this data is visible to QEMU and used for migration, we only guarantee valid values to user space when KVM_SYNC_VRS is set. As that is only the case when we have vector register support, we are on the safe side. Fixes: b5510d9b68c3 ("s390/fpu: always enable the vector facility if it is available") Cc: stable@vger.kernel.org # v4.4 d9a3a09af54d s390/kvm: remove dependency on struct save_area definition Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> [adopt to d9a3a09af54d]
* | KVM: s390: Enable the KVM-VFIO deviceDong Jia Shi2016-01-26
| | | | | | | | | | | | | | | | | | | | | | | | The KVM-VFIO device is used by the QEMU VFIO device. It is used to record the list of in-use VFIO groups so that KVM can manipulate them. While we don't need this on s390 currently, let's try to be like everyone else. Signed-off-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: fix guest fprs memory leakDavid Hildenbrand2016-01-26
|/ | | | | | | | | | | | fprs is never freed, therefore resulting in a memory leak if kvm_vcpu_init() fails or the vcpu is destroyed. Fixes: 9977e886cbbc ("s390/kernel: lazy restore fpu registers") Cc: stable@vger.kernel.org # v4.3+ Reported-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Eric Farman <farman@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2016-01-13
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull s390 updates from Martin Schwidefsky: "Among the traditional bug fixes and cleanups are some improvements: - A tool to generated the facility lists, generating the bit fields by hand has been a source of bugs in the past - The spinlock loop is reordered to avoid bursts of hypervisor calls - Add support for the open-for-business interface to the service element - The get_cpu call is added to the vdso - A set of tracepoints is defined for the common I/O layer - The deprecated sclp_cpi module is removed - Update default configuration" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits) s390/sclp: fix possible control register corruption s390: fix normalization bug in exception table sorting s390/configs: update default configurations s390/vdso: optimize getcpu system call s390: drop smp_mb in vdso_init s390: rename struct _lowcore to struct lowcore s390/mem_detect: use unsigned longs s390/ptrace: get rid of long longs in psw_bits s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK s390/Kconfig: remove pointless 64 bit dependencies s390/dasd: fix failfast for disconnected devices s390/con3270: testing return kzalloc retval s390/hmcdrv: constify hmcdrv_ftp_ops structs s390/cio: add NULL test s390/cio: Change I/O instructions from inline to normal functions s390/cio: Introduce common I/O layer tracepoints s390/cio: Consolidate inline assemblies and related data definitions s390/cio: Fix incorrect xsch opcode specification s390/cio: Remove unused inline assemblies ...
| * s390: rename struct _lowcore to struct lowcoreHeiko Carstens2016-01-11
| | | | | | | | | | | | | | | | | | | | | | | | | | Finally get rid of the leading underscore. I tried this already two or three years ago, however Michael Holzheu objected since this would break the crash utility (again). However Michael integrated support for the new name into the crash utility back then, so it doesn't break if the name will be changed now. So finally get rid of the ever confusing leading underscore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
| * s390/kvm: remove dependency on struct save_area definitionMartin Schwidefsky2015-11-27
| | | | | | | | | | | | | | Replace the offsets based on the struct area_area with the offset constants from asm-offsets.c based on the struct _lowcore. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* | KVM: s390: implement the RI support of guestFan Zhang2016-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds runtime instrumentation support for KVM guest. We need to setup a save area for the runtime instrumentation-controls control block(RICCB) and implement the necessary interfaces to live migrate the guest settings. We setup the sie control block in a way, that the runtime instrumentation instructions of a guest are handled by hardware. We also add a capability KVM_CAP_S390_RI to make this feature opt-in as it needs migration support. Signed-off-by: Fan Zhang <zhangfan@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | kvm/s390: drop unpaired smp_mbMichael S. Tsirkin2016-01-07
| | | | | | | | | | | | | | | | | | | | | | smp_mb on vcpu destroy isn't paired with anything, violating pairing rules, and seems to be useless. Drop it. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <1452010811-25486-1-git-send-email-mst@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: consider system MHA for guest storageGuenther Hutzl2015-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Verify that the guest maximum storage address is below the MHA (maximum host address) value allowed on the host. Acked-by: Michael Holzheu <holzheu@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: Guenther Hutzl <hutzl@linux.vnet.ibm.com> Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> [adopt to match recent limit,size changes] Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: fix mismatch between user and in-kernel guest limitDominik Dingel2015-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While the userspace interface requests the maximum size the gmap code expects to get a maximum address. This error resulted in bigger page tables than necessary for some guest sizes, e.g. a 2GB guest used 3 levels instead of 2. At the same time we introduce KVM_S390_NO_MEM_LIMIT, which allows in a bright future that a guest spans the complete 64 bit address space. We also switch to TASK_MAX_SIZE for the initial memory size, this is a cosmetic change as the previous size also resulted in a 4 level pagetable creation. Reported-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: obey kptr_restrict in tracesChristian Borntraeger2015-12-15
| | | | | | | | | | | | | | | | | | | | | | The s390dbf and trace events provide a debugfs interface. If kptr_restrict is active, we should not expose kernel pointers. We can fence the debugfs output by using %pK instead of %p. Cc: Kees Cook <keescook@chromium.org> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: use assignment instead of memcpyChristian Borntraeger2015-12-15
| | | | | | | | | | | | | | | | | | Replace two memcpy with proper assignment. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: remove redudant assigment of error codeChristian Borntraeger2015-11-30
| | | | | | | | | | | | | | | | rc already contains -ENOMEM, no need to assign it twice. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
* | KVM: s390: remove pointless test_facility(2) checkHeiko Carstens2015-11-30
| | | | | | | | | | | | | | | | This evaluates always to 'true'. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: don't load kvm without virtualization supportDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we don't have support for virtualization (SIE), e.g. when running under a hypervisor not supporting execution of the SIE instruction, we should immediately abort loading the kvm module, as the SIE instruction cannot be enabled dynamically. Currently, the SIE instructions fails with an exception on a non-SIE host, resulting in the guest making no progress, instead of failing hard. Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: don't switch to ESCA for ucontrolDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | | | | | | | sca_add_vpcu is not called for ucontrol guests. We must also not apply the sca checking for sca_can_add_vcpu as ucontrol guests do not have to follow the sca limits. As common code already checks that id < KVM_MAX_VCPUS all other data structures are safe as well. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: cleanup sca_add_vcpuDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | Now that we already have kvm and the VCPU id set for the VCPU, we can convert sda_add_vcpu to look much more like sda_del_vcpu. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: always set/clear the SCA sda fieldDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | | | Let's always set and clear the sda when enabling/disabling a VCPU. Dealing with sda being set to something else makes no sense anymore as we enable a VCPU in the SCA now after it has been registered at the VM. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: fix SCA related races and double useDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If something goes wrong in kvm_arch_vcpu_create, the VCPU has already been added to the sca but will never be removed. Trying to create VCPUs with duplicate ids (e.g. after a failed attempt) is problematic. Also, when creating multiple VCPUs in parallel, we could theoretically forget to set the correct SCA when the switch to ESCA happens just before the VCPU is registered. Let's add the VCPU to the SCA in kvm_arch_vcpu_postcreate, where we can be sure that no duplicate VCPU with the same id is around and the VCPU has already been registered at the VM. We also have to make sure to update ECB at that point. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: we always have a SCADavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | | | Having no sca can never happen, even when something goes wrong when switching to ESCA. Otherwise we would have a serious bug. Let's remove this superfluous check. Acked-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: fast path for sca_ext_call_pendingDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | If CPUSTAT_ECALL_PEND isn't set, we can't have an external call pending, so we can directly avoid taking the lock. 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>
* | KVM: s390: Enable up to 248 VCPUs per VMEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | | | This patch allows s390 to have more than 64 VCPUs for a guest (up to 248 for memory usage considerations), if supported by the underlaying hardware (sclp.has_esca). Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: Introduce switching codeEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds code that performs transparent switch to Extended SCA on addition of 65th VCPU in a VM. Disposal of ESCA is added too. The entier ESCA functionality, however, is still not enabled. The enablement will be provided in a separate patch. This patch also uses read/write lock protection of SCA and its subfields for possible disposal at the BSCA-to-ESCA transition. While only Basic SCA needs such a protection (for the swap), any SCA access is now guarded. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: Make provisions for ESCA utilizationEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | | | | | | | This patch updates the routines (sca_*) to provide transparent access to and manipulation on the data for both Basic and Extended SCA in use. The kvm.arch.sca is generalized to (void *) to handle BSCA/ESCA cases. Also the kvm.arch.use_esca flag is provided. The actual functionality is kept the same. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: Introduce new structuresEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds new structures and updates some existing ones to provide the base for Extended SCA functionality. The old sca_* structures were renamed to bsca_* to keep things uniform. The access to fields of SIGP controls were turned into bitfields instead of hardcoded bitmasks. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: Provide SCA-aware helpers for VCPU add/delEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | | | This patch provides SCA-aware helpers to create/delete a VCPU. This is to prepare for upcoming introduction of Extended SCA support. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: Generalize access to SIGP controlsEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | This patch generalizes access to the SIGP controls, which is a part of SCA. This is to prepare for upcoming introduction of Extended SCA support. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: Generalize access to IPTE controlsEugene (jno) Dvurechenski2015-11-30
| | | | | | | | | | | | | | | | This patch generalizes access to the IPTE controls, which is a part of SCA. This is to prepare for upcoming introduction of Extended SCA support. Signed-off-by: Eugene (jno) Dvurechenski <jno@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: s390: rewrite vcpu_post_run and drop out earlyDavid Hildenbrand2015-11-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's rewrite this function to better reflect how we actually handle exit_code. By dropping out early we can save a few cycles. This especially speeds up sie exits caused by host irqs. Also, let's move the special -EOPNOTSUPP for intercepts to the place where it belongs and convert it to -EREMOTE. Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* | KVM: Use common function for VCPU lookup by idDavid Hildenbrand2015-11-30
|/ | | | | | | | | | Let's reuse the new common function for VPCU lookup by id. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> [split out the new function into a separate patch]
* KVM: s390: fix wrong lookup of VCPUs by array indexDavid Hildenbrand2015-11-19
| | | | | | | | | | | | | | | | For now, VCPUs were always created sequentially with incrementing VCPU ids. Therefore, the index in the VCPUs array matched the id. As sequential creation might change with cpu hotplug, let's use the correct lookup function to find a VCPU by id, not array index. Let's also use kvm_lookup_vcpu() for validation of the sending VCPU on external call injection. Reviewed-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> Cc: stable@vger.kernel.org # db27a7a KVM: Provide function for VCPU lookup by id
* KVM: s390: avoid memory overwrites on emergency signal injectionDavid Hildenbrand2015-11-19
| | | | | | | | | | | | | | Commit 383d0b050106 ("KVM: s390: handle pending local interrupts via bitmap") introduced a possible memory overwrite from user space. User space could pass an invalid emergency signal code (sending VCPU) and therefore exceed the bitmap. Let's take care of this case and check that the id is in the valid range. Reviewed-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Cc: stable@vger.kernel.org # v3.19+ db27a7a KVM: Provide function for VCPU lookup by id Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: fix pfmf intercept handlerHeiko Carstens2015-11-19
| | | | | | | | The pfmf intercept handler should check if the EDAT 1 facility is installed in the guest, not if it is installed in the host. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
* KVM: s390: enable SIMD only when no VCPUs were createdDavid Hildenbrand2015-11-19
| | | | | | | | | | | | | | | | We should never allow to enable/disable any facilities for the guest when other VCPUs were already created. kvm_arch_vcpu_(load|put) relies on SIMD not changing during runtime. If somebody would create and run VCPUs and then decides to enable SIMD, undefined behaviour could be possible (e.g. vector save area not being set up). Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Cc: stable@vger.kernel.org # 4.1+
* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2015-11-05
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "First batch of KVM changes for 4.4. s390: A bunch of fixes and optimizations for interrupt and time handling. PPC: Mostly bug fixes. ARM: No big features, but many small fixes and prerequisites including: - a number of fixes for the arch-timer - introducing proper level-triggered semantics for the arch-timers - a series of patches to synchronously halt a guest (prerequisite for IRQ forwarding) - some tracepoint improvements - a tweak for the EL2 panic handlers - some more VGIC cleanups getting rid of redundant state x86: Quite a few changes: - support for VT-d posted interrupts (i.e. PCI devices can inject interrupts directly into vCPUs). This introduces a new component (in virt/lib/) that connects VFIO and KVM together. The same infrastructure will be used for ARM interrupt forwarding as well. - more Hyper-V features, though the main one Hyper-V synthetic interrupt controller will have to wait for 4.5. These will let KVM expose Hyper-V devices. - nested virtualization now supports VPID (same as PCID but for vCPUs) which makes it quite a bit faster - for future hardware that supports NVDIMM, there is support for clflushopt, clwb, pcommit - support for "split irqchip", i.e. LAPIC in kernel + IOAPIC/PIC/PIT in userspace, which reduces the attack surface of the hypervisor - obligatory smattering of SMM fixes - on the guest side, stable scheduler clock support was rewritten to not require help from the hypervisor" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (123 commits) KVM: VMX: Fix commit which broke PML KVM: x86: obey KVM_X86_QUIRK_CD_NW_CLEARED in kvm_set_cr0() KVM: x86: allow RSM from 64-bit mode KVM: VMX: fix SMEP and SMAP without EPT KVM: x86: move kvm_set_irq_inatomic to legacy device assignment KVM: device assignment: remove pointless #ifdefs KVM: x86: merge kvm_arch_set_irq with kvm_set_msi_inatomic KVM: x86: zero apic_arb_prio on reset drivers/hv: share Hyper-V SynIC constants with userspace KVM: x86: handle SMBASE as physical address in RSM KVM: x86: add read_phys to x86_emulate_ops KVM: x86: removing unused variable KVM: don't pointlessly leave KVM_COMPAT=y in non-KVM configs KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr() KVM: arm/arm64: Clean up vgic_retire_lr() and surroundings KVM: arm/arm64: Optimize away redundant LR tracking KVM: s390: use simple switch statement as multiplexer KVM: s390: drop useless newline in debugging data KVM: s390: SCA must not cross page boundaries KVM: arm: Do not indent the arguments of DECLARE_BITMAP ...
| * KVM: s390: use simple switch statement as multiplexerChristian Borntraeger2015-10-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently do some magic shifting (by exploiting that exit codes are always a multiple of 4) and a table lookup to jump into the exit handlers. This causes some calculations and checks, just to do an potentially expensive function call. Changing that to a switch statement gives the compiler the chance to inline and dynamically decide between jump tables or inline compare and branches. In addition it makes the code more readable. bloat-o-meter gives me a small reduction in code size: add/remove: 0/7 grow/shrink: 1/1 up/down: 986/-1334 (-348) function old new delta kvm_handle_sie_intercept 72 1058 +986 handle_prog 704 696 -8 handle_noop 54 - -54 handle_partial_execution 60 - -60 intercept_funcs 120 - -120 handle_instruction 198 - -198 handle_validity 210 - -210 handle_stop 316 - -316 handle_external_interrupt 368 - -368 Right now my gcc does conditional branches instead of jump tables. The inlining seems to give us enough cycles as some micro-benchmarking shows minimal improvements, but still in noise. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
| * KVM: s390: drop useless newline in debugging dataChristian Borntraeger2015-10-29
| | | | | | | | | | | | | | | | the s390 debug feature does not need newlines. In fact it will result in empty lines. Get rid of 4 leftovers. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
| * KVM: s390: SCA must not cross page boundariesDavid Hildenbrand2015-10-29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We seemed to have missed a few corner cases in commit f6c137ff00a4 ("KVM: s390: randomize sca address"). The SCA has a maximum size of 2112 bytes. By setting the sca_offset to some unlucky numbers, we exceed the page. 0x7c0 (1984) -> Fits exactly 0x7d0 (2000) -> 16 bytes out 0x7e0 (2016) -> 32 bytes out 0x7f0 (2032) -> 48 bytes out One VCPU entry is 32 bytes long. For the last two cases, we actually write data to the other page. 1. The address of the VCPU. 2. Injection/delivery/clearing of SIGP externall calls via SIGP IF. Especially the 2. happens regularly. So this could produce two problems: 1. The guest losing/getting external calls. 2. Random memory overwrites in the host. So this problem happens on every 127 + 128 created VM with 64 VCPUs. Cc: stable@vger.kernel.org # v3.15+ 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>
| * KVM: s390: factor out reading of the guest TOD clockDavid Hildenbrand2015-10-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Let's factor this out and always use get_tod_clock_fast() when reading the guest TOD. STORE CLOCK FAST does not do serialization and, therefore, might result in some fuzziness between different processors in a way that subsequent calls on different CPUs might have time stamps that are earlier. This semantics is fine though for all KVM use cases. To make it obvious that the new function has STORE CLOCK FAST semantics we name it kvm_s390_get_tod_clock_fast. With this patch, we only have a handful of places were we have to care about STP sync (using preempt_disable() logic). Reviewed-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>
| * KVM: s390: factor out and fix setting of guest TOD clockDavid Hildenbrand2015-10-13
| | | | | | | | | | | | | | | | | | | | | | Let's move that whole logic into one function. We now always use unsigned values when calculating the epoch (to avoid over/underflow defined). Also, we always have to get all VCPUs out of SIE before doing the update to avoid running differing VCPUs with different TODs. 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>
| * KVM: s390: switch to get_tod_clock() and fix STP sync racesDavid Hildenbrand2015-10-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Nobody except early.c makes use of store_tod_clock() to handle the cc. So if we would get a cc != 0, we would be in more trouble. Let's replace all users with get_tod_clock(). Returning a cc on an ioctl sounded strange either way. We can now also easily move the get_tod_clock() call into the preempt_disable() section. This is in fact necessary to make the STP sync work as expected. Otherwise the host TOD could change and we would end up with a wrong epoch calculation. Reviewed-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>
| * KVM: s390: correctly handle injection of pgm irqs and per eventsDavid Hildenbrand2015-10-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | PER events can always co-exist with other program interrupts. For now, we always overwrite all program interrupt parameters when injecting any type of program interrupt. Let's handle that correctly by only overwriting the relevant portion of the program interrupt parameters. Therefore we can now inject PER events and ordinary program interrupts concurrently, resulting in no loss of program interrupts. This will especially by helpful when manually detecting PER events later - as both types might be triggered during one SIE exit. Reviewed-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>
| * KVM: s390: simplify in-kernel program irq injectionDavid Hildenbrand2015-10-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The main reason to keep program injection in kernel separated until now was that we were able to do some checking, if really only the owning thread injects program interrupts (via waitqueue_active(li->wq)). This BUG_ON was never triggered and the chances of really hitting it, if another thread injected a program irq to another vcpu, were very small. Let's drop this check and turn kvm_s390_inject_program_int() and kvm_s390_inject_prog_irq() into simple inline functions that makes use of kvm_s390_inject_vcpu(). __must_check can be dropped as they are implicitely given by kvm_s390_inject_vcpu(), to avoid ugly long function prototypes. Reviewed-by: Jens Freimann <jfrei@linux.vnet.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-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>
| * KVM: s390: drop out early in kvm_s390_has_irq()David Hildenbrand2015-10-13
| | | | | | | | | | | | | | | | | | | | Let's get rid of the local variable and exit directly if we found any pending interrupt. This is not only faster, but also better readable. Reviewed-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>
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