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2019-08-28Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "Hot on the heels of our last set of fixes are a few more for -rc7. Two of them are fixing issues with our virtual interrupt controller implementation in KVM/arm, while the other is a longstanding but straightforward kallsyms fix which was been acked by Masami and resolves an initialisation failure in kprobes observed on arm64. - Fix GICv2 emulation bug (KVM) - Fix deadlock in virtual GIC interrupt injection code (KVM) - Fix kprobes blacklist init failure due to broken kallsyms lookup" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: KVM: arm/arm64: vgic-v2: Handle SGI bits in GICD_I{S,C}PENDR0 as WI KVM: arm/arm64: vgic: Fix potential deadlock when ap_list is long kallsyms: Don't let kallsyms_lookup_size_offset() fail on retrieving the first symbol
2019-08-28KVM: arm/arm64: vgic-v2: Handle SGI bits in GICD_I{S,C}PENDR0 as WIMarc Zyngier
A guest is not allowed to inject a SGI (or clear its pending state) by writing to GICD_ISPENDR0 (resp. GICD_ICPENDR0), as these bits are defined as WI (as per ARM IHI 0048B 4.3.7 and 4.3.8). Make sure we correctly emulate the architecture. Fixes: 96b298000db4 ("KVM: arm/arm64: vgic-new: Add PENDING registers handlers") Cc: stable@vger.kernel.org # 4.7+ Reported-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-27KVM: arm/arm64: vgic: Fix potential deadlock when ap_list is longHeyi Guo
If the ap_list is longer than 256 entries, merge_final() in list_sort() will call the comparison callback with the same element twice, causing a deadlock in vgic_irq_cmp(). Fix it by returning early when irqa == irqb. Cc: stable@vger.kernel.org # 4.7+ Fixes: 8e4447457965 ("KVM: arm/arm64: vgic-new: Add IRQ sorting") Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Heyi Guo <guoheyi@huawei.com> [maz: massaged commit log and patch, added Fixes and Cc-stable] Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Will Deacon <will@kernel.org>
2019-08-24Merge tag 'kvmarm-fixes-for-5.3-3' of ↵Will Deacon
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm/fixes Pull KVM/arm fixes from Marc Zyngier as per Paulo's request at: https://lkml.kernel.org/r/21ae69a2-2546-29d0-bff6-2ea825e3d968@redhat.com "One (hopefully last) set of fixes for KVM/arm for 5.3: an embarassing MMIO emulation regression, and a UBSAN splat. Oh well... - Don't overskip instructions on MMIO emulation - Fix UBSAN splat when initializing PPI priorities" * tag 'kvmarm-fixes-for-5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm: KVM: arm/arm64: VGIC: Properly initialise private IRQ affinity KVM: arm/arm64: Only skip MMIO insn once
2019-08-23KVM: arm/arm64: VGIC: Properly initialise private IRQ affinityAndre Przywara
At the moment we initialise the target *mask* of a virtual IRQ to the VCPU it belongs to, even though this mask is only defined for GICv2 and quickly runs out of bits for many GICv3 guests. This behaviour triggers an UBSAN complaint for more than 32 VCPUs: ------ [ 5659.462377] UBSAN: Undefined behaviour in virt/kvm/arm/vgic/vgic-init.c:223:21 [ 5659.471689] shift exponent 32 is too large for 32-bit type 'unsigned int' ------ Also for GICv3 guests the reporting of TARGET in the "vgic-state" debugfs dump is wrong, due to this very same problem. Because there is no requirement to create the VGIC device before the VCPUs (and QEMU actually does it the other way round), we can't safely initialise mpidr or targets in kvm_vgic_vcpu_init(). But since we touch every private IRQ for each VCPU anyway later (in vgic_init()), we can just move the initialisation of those fields into there, where we definitely know the VGIC type. On the way make sure we really have either a VGICv2 or a VGICv3 device, since the existing code is just checking for "VGICv3 or not", silently ignoring the uninitialised case. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reported-by: Dave Martin <dave.martin@arm.com> Tested-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-22KVM: arm/arm64: Only skip MMIO insn onceAndrew Jones
If after an MMIO exit to userspace a VCPU is immediately run with an immediate_exit request, such as when a signal is delivered or an MMIO emulation completion is needed, then the VCPU completes the MMIO emulation and immediately returns to userspace. As the exit_reason does not get changed from KVM_EXIT_MMIO in these cases we have to be careful not to complete the MMIO emulation again, when the VCPU is eventually run again, because the emulation does an instruction skip (and doing too many skips would be a waste of guest code :-) We need to use additional VCPU state to track if the emulation is complete. As luck would have it, we already have 'mmio_needed', which even appears to be used in this way by other architectures already. Fixes: 0d640732dbeb ("arm64: KVM: Skip MMIO insn after emulation") Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-09Merge tag 'kvmarm-fixes-for-5.3-2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm fixes for 5.3, take #2 - Fix our system register reset so that we stop writing non-sensical values to them, and track which registers get reset instead. - Sync VMCR back from the GIC on WFI so that KVM has an exact vue of PMR. - Reevaluate state of HW-mapped, level triggered interrupts on enable.
2019-08-09Merge tag 'kvmarm-fixes-for-5.3' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm fixes for 5.3 - A bunch of switch/case fall-through annotation, fixing one actual bug - Fix PMU reset bug - Add missing exception class debug strings
2019-08-09kvm: remove unnecessary PageReserved checkPaolo Bonzini
The same check is already done in kvm_is_reserved_pfn. Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-09KVM: arm/arm64: vgic: Reevaluate level sensitive interrupts on enableAlexandru Elisei
A HW mapped level sensitive interrupt asserted by a device will not be put into the ap_list if it is disabled at the VGIC level. When it is enabled again, it will be inserted into the ap_list and written to a list register on guest entry regardless of the state of the device. We could argue that this can also happen on real hardware, when the command to enable the interrupt reached the GIC before the device had the chance to de-assert the interrupt signal; however, we emulate the distributor and redistributors in software and we can do better than that. Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-05KVM: arm/arm64: Sync ICH_VMCR_EL2 back when about to blockMarc Zyngier
Since commit commit 328e56647944 ("KVM: arm/arm64: vgic: Defer touching GICH_VMCR to vcpu_load/put"), we leave ICH_VMCR_EL2 (or its GICv2 equivalent) loaded as long as we can, only syncing it back when we're scheduled out. There is a small snag with that though: kvm_vgic_vcpu_pending_irq(), which is indirectly called from kvm_vcpu_check_block(), needs to evaluate the guest's view of ICC_PMR_EL1. At the point were we call kvm_vcpu_check_block(), the vcpu is still loaded, and whatever changes to PMR is not visible in memory until we do a vcpu_put(). Things go really south if the guest does the following: mov x0, #0 // or any small value masking interrupts msr ICC_PMR_EL1, x0 [vcpu preempted, then rescheduled, VMCR sampled] mov x0, #ff // allow all interrupts msr ICC_PMR_EL1, x0 wfi // traps to EL2, so samping of VMCR [interrupt arrives just after WFI] Here, the hypervisor's view of PMR is zero, while the guest has enabled its interrupts. kvm_vgic_vcpu_pending_irq() will then say that no interrupts are pending (despite an interrupt being received) and we'll block for no reason. If the guest doesn't have a periodic interrupt firing once it has blocked, it will stay there forever. To avoid this unfortuante situation, let's resync VMCR from kvm_arch_vcpu_blocking(), ensuring that a following kvm_vcpu_check_block() will observe the latest value of PMR. This has been found by booting an arm64 Linux guest with the pseudo NMI feature, and thus using interrupt priorities to mask interrupts instead of the usual PSTATE masking. Cc: stable@vger.kernel.org # 4.12 Fixes: 328e56647944 ("KVM: arm/arm64: vgic: Defer touching GICH_VMCR to vcpu_load/put") Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-08-05KVM: no need to check return value of debugfs_create functionsGreg KH
When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Also, when doing this, change kvm_arch_create_vcpu_debugfs() to return void instead of an integer, as we should not care at all about if this function actually does anything or not. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: <x86@kernel.org> Cc: <kvm@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05KVM: remove kvm_arch_has_vcpu_debugfs()Paolo Bonzini
There is no need for this function as all arches have to implement kvm_arch_create_vcpu_debugfs() no matter what. A #define symbol let us actually simplify the code. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05KVM: Fix leak vCPU's VMCS value into other pCPUWanpeng Li
After commit d73eb57b80b (KVM: Boost vCPUs that are delivering interrupts), a five years old bug is exposed. Running ebizzy benchmark in three 80 vCPUs VMs on one 80 pCPUs Skylake server, a lot of rcu_sched stall warning splatting in the VMs after stress testing: INFO: rcu_sched detected stalls on CPUs/tasks: { 4 41 57 62 77} (detected by 15, t=60004 jiffies, g=899, c=898, q=15073) Call Trace: flush_tlb_mm_range+0x68/0x140 tlb_flush_mmu.part.75+0x37/0xe0 tlb_finish_mmu+0x55/0x60 zap_page_range+0x142/0x190 SyS_madvise+0x3cd/0x9c0 system_call_fastpath+0x1c/0x21 swait_active() sustains to be true before finish_swait() is called in kvm_vcpu_block(), voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin() loop greatly increases the probability condition kvm_arch_vcpu_runnable(vcpu) is checked and can be true, when APICv is enabled the yield-candidate vCPU's VMCS RVI field leaks(by vmx_sync_pir_to_irr()) into spinning-on-a-taken-lock vCPU's current VMCS. This patch fixes it by checking conservatively a subset of events. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Marc Zyngier <Marc.Zyngier@arm.com> Cc: stable@vger.kernel.org Fixes: 98f4a1467 (KVM: add kvm_arch_vcpu_runnable() test to kvm_vcpu_on_spin() loop) Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-08-05KVM: Check preempted_in_kernel for involuntary preemptionWanpeng Li
preempted_in_kernel is updated in preempt_notifier when involuntary preemption ocurrs, it can be stale when the voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin() loop. This patch lets it just check preempted_in_kernel for involuntary preemption. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-26KVM: arm: vgic-v3: Mark expected switch fall-throughAnders Roxell
When fall-through warnings was enabled by default the following warnings was starting to show up: ../virt/kvm/arm/hyp/vgic-v3-sr.c: In function ‘__vgic_v3_save_aprs’: ../virt/kvm/arm/hyp/vgic-v3-sr.c:351:24: warning: this statement may fall through [-Wimplicit-fallthrough=] cpu_if->vgic_ap0r[2] = __vgic_v3_read_ap0rn(2); ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~ ../virt/kvm/arm/hyp/vgic-v3-sr.c:352:2: note: here case 6: ^~~~ ../virt/kvm/arm/hyp/vgic-v3-sr.c:353:24: warning: this statement may fall through [-Wimplicit-fallthrough=] cpu_if->vgic_ap0r[1] = __vgic_v3_read_ap0rn(1); ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~ ../virt/kvm/arm/hyp/vgic-v3-sr.c:354:2: note: here default: ^~~~~~~ Rework so that the compiler doesn't warn about fall-through. Fixes: d93512ef0f0e ("Makefile: Globally enable fall-through warning") Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Marc Zyngier <maz@kernel.org>
2019-07-24Documentation: move Documentation/virtual to Documentation/virtChristoph Hellwig
Renaming docs seems to be en vogue at the moment, so fix on of the grossly misnamed directories. We usually never use "virtual" as a shortcut for virtualization in the kernel, but always virt, as seen in the virt/ top-level directory. Fix up the documentation to match that. Fixes: ed16648eb5b8 ("Move kvm, uml, and lguest subdirectories under a common "virtual" directory, I.E:") Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-23KVM: arm/arm64: Introduce kvm_pmu_vcpu_init() to setup PMU counter indexZenghui Yu
We use "pmc->idx" and the "chained" bitmap to determine if the pmc is chained, in kvm_pmu_pmc_is_chained(). But idx might be uninitialized (and random) when we doing this decision, through a KVM_ARM_VCPU_INIT ioctl -> kvm_pmu_vcpu_reset(). And the test_bit() against this random idx will potentially hit a KASAN BUG [1]. In general, idx is the static property of a PMU counter that is not expected to be modified across resets, as suggested by Julien. It looks more reasonable if we can setup the PMU counter idx for a vcpu in its creation time. Introduce a new function - kvm_pmu_vcpu_init() for this basic setup. Oh, and the KASAN BUG will get fixed this way. [1] https://www.spinics.net/lists/kvm-arm/msg36700.html Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters") Suggested-by: Andrew Murray <andrew.murray@arm.com> Suggested-by: Julien Thierry <julien.thierry@arm.com> Acked-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-20KVM: Boost vCPUs that are delivering interruptsWanpeng Li
Inspired by commit 9cac38dd5d (KVM/s390: Set preempted flag during vcpu wakeup and interrupt delivery), we want to also boost not just lock holders but also vCPUs that are delivering interrupts. Most smp_call_function_many calls are synchronous, so the IPI target vCPUs are also good yield candidates. This patch introduces vcpu->ready to boost vCPUs during wakeup and interrupt delivery time; unlike s390 we do not reuse vcpu->preempted so that voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin, but vmx_vcpu_pi_put is not affected (VT-d PI handles voluntary preemption separately, in pi_pre_block). Testing on 80 HT 2 socket Xeon Skylake server, with 80 vCPUs VM 80GB RAM: ebizzy -M vanilla boosting improved 1VM 21443 23520 9% 2VM 2800 8000 180% 3VM 1800 3100 72% Testing on my Haswell desktop 8 HT, with 8 vCPUs VM 8GB RAM, two VMs, one running ebizzy -M, the other running 'stress --cpu 2': w/ boosting + w/o pv sched yield(vanilla) vanilla boosting improved 1570 4000 155% w/ boosting + w/ pv sched yield(vanilla) vanilla boosting improved 1844 5157 179% w/o boosting, perf top in VM: 72.33% [kernel] [k] smp_call_function_many 4.22% [kernel] [k] call_function_i 3.71% [kernel] [k] async_page_fault w/ boosting, perf top in VM: 38.43% [kernel] [k] smp_call_function_many 6.31% [kernel] [k] async_page_fault 6.13% libc-2.23.so [.] __memcpy_avx_unaligned 4.88% [kernel] [k] call_function_interrupt Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Marc Zyngier <maz@kernel.org> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-12Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - support for chained PMU counters in guests - improved SError handling - handle Neoverse N1 erratum #1349291 - allow side-channel mitigation status to be migrated - standardise most AArch64 system register accesses to msr_s/mrs_s - fix host MPIDR corruption on 32bit - selftests ckleanups x86: - PMU event {white,black}listing - ability for the guest to disable host-side interrupt polling - fixes for enlightened VMCS (Hyper-V pv nested virtualization), - new hypercall to yield to IPI target - support for passing cstate MSRs through to the guest - lots of cleanups and optimizations Generic: - Some txt->rST conversions for the documentation" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (128 commits) Documentation: virtual: Add toctree hooks Documentation: kvm: Convert cpuid.txt to .rst Documentation: virtual: Convert paravirt_ops.txt to .rst KVM: x86: Unconditionally enable irqs in guest context KVM: x86: PMU Event Filter kvm: x86: Fix -Wmissing-prototypes warnings KVM: Properly check if "page" is valid in kvm_vcpu_unmap KVM: arm/arm64: Initialise host's MPIDRs by reading the actual register KVM: LAPIC: Retry tune per-vCPU timer_advance_ns if adaptive tuning goes insane kvm: LAPIC: write down valid APIC registers KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_s KVM: doc: Add API documentation on the KVM_REG_ARM_WORKAROUNDS register KVM: arm/arm64: Add save/restore support for firmware workaround state arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests KVM: arm/arm64: Support chained PMU counters KVM: arm/arm64: Remove pmc->bitmask KVM: arm/arm64: Re-create event when setting counter value KVM: arm/arm64: Extract duplicated code to own function KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functions KVM: LAPIC: ARBPRI is a reserved register for x2APIC ...
2019-07-12arm64: switch to generic version of pte allocationMike Rapoport
The PTE allocations in arm64 are identical to the generic ones modulo the GFP flags. Using the generic pte_alloc_one() functions ensures that the user page tables are allocated with __GFP_ACCOUNT set. The arm64 definition of PGALLOC_GFP is removed and replaced with GFP_PGTABLE_USER for p[gum]d_alloc_one() for the user page tables and GFP_PGTABLE_KERNEL for the kernel page tables. The KVM memory cache is now using GFP_PGTABLE_USER. The mappings created with create_pgd_mapping() are now using GFP_PGTABLE_KERNEL. The conversion to the generic version of pte_free_kernel() removes the NULL check for pte. The pte_free() version on arm64 is identical to the generic one and can be simply dropped. [cai@lca.pw: fix a bogus GFP flag in pgd_alloc()] Link: https://lore.kernel.org/r/1559656836-24940-1-git-send-email-cai@lca.pw/ [and fix it more] Link: https://lore.kernel.org/linux-mm/20190617151252.GF16810@rapoport-lnx/ Link: http://lkml.kernel.org/r/1557296232-15361-5-git-send-email-rppt@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Guo Ren <ren_guo@c-sky.com> Cc: Helge Deller <deller@gmx.de> Cc: Ley Foon Tan <lftan@altera.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Hocko <mhocko@suse.com> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Russell King <linux@armlinux.org.uk> Cc: Sam Creasey <sammy@sammy.net> Cc: Vincent Chen <deanbo422@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-11Merge tag 'kvm-arm-for-5.3' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm updates for 5.3 - Add support for chained PMU counters in guests - Improve SError handling - Handle Neoverse N1 erratum #1349291 - Allow side-channel mitigation status to be migrated - Standardise most AArch64 system register accesses to msr_s/mrs_s - Fix host MPIDR corruption on 32bit
2019-07-10KVM: Properly check if "page" is valid in kvm_vcpu_unmapKarimAllah Ahmed
The field "page" is initialized to KVM_UNMAPPED_PAGE when it is not used (i.e. when the memory lives outside kernel control). So this check will always end up using kunmap even for memremap regions. Fixes: e45adf665a53 ("KVM: Introduce a new guest mapping API") Cc: stable@vger.kernel.org Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-07-08KVM: arm/arm64: Initialise host's MPIDRs by reading the actual registerMarc Zyngier
As part of setting up the host context, we populate its MPIDR by using cpu_logical_map(). It turns out that contrary to arm64, cpu_logical_map() on 32bit ARM doesn't return the *full* MPIDR, but a truncated version. This leaves the host MPIDR slightly corrupted after the first run of a VM, since we won't correctly restore the MPIDR on exit. Oops. Since we cannot trust cpu_logical_map(), let's adopt a different strategy. We move the initialization of the host CPU context as part of the per-CPU initialization (which, in retrospect, makes a lot of sense), and directly read the MPIDR from the HW. This is guaranteed to work on both arm and arm64. Reported-by: Andre Przywara <Andre.Przywara@arm.com> Tested-by: Andre Przywara <Andre.Przywara@arm.com> Fixes: 32f139551954 ("arm/arm64: KVM: Statically configure the host's view of MPIDR") Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm64: Migrate _elx sysreg accessors to msr_s/mrs_sDave Martin
Currently, the {read,write}_sysreg_el*() accessors for accessing particular ELs' sysregs in the presence of VHE rely on some local hacks and define their system register encodings in a way that is inconsistent with the core definitions in <asm/sysreg.h>. As a result, it is necessary to add duplicate definitions for any system register that already needs a definition in sysreg.h for other reasons. This is a bit of a maintenance headache, and the reasons for the _el*() accessors working the way they do is a bit historical. This patch gets rid of the shadow sysreg definitions in <asm/kvm_hyp.h>, converts the _el*() accessors to use the core __msr_s/__mrs_s interface, and converts all call sites to use the standard sysreg #define names (i.e., upper case, with SYS_ prefix). This patch will conflict heavily anyway, so the opportunity to clean up some bad whitespace in the context of the changes is taken. The change exposes a few system registers that have no sysreg.h definition, due to msr_s/mrs_s being used in place of msr/mrs: additions are made in order to fill in the gaps. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoffer Dall <christoffer.dall@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Link: https://www.spinics.net/lists/kvm-arm/msg31717.html [Rebased to v4.21-rc1] Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> [Rebased to v5.2-rc5, changelog updates] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm/arm64: Add save/restore support for firmware workaround stateAndre Przywara
KVM implements the firmware interface for mitigating cache speculation vulnerabilities. Guests may use this interface to ensure mitigation is active. If we want to migrate such a guest to a host with a different support level for those workarounds, migration might need to fail, to ensure that critical guests don't loose their protection. Introduce a way for userland to save and restore the workarounds state. On restoring we do checks that make sure we don't downgrade our mitigation level. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Steven Price <steven.price@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05arm64: KVM: Propagate full Spectre v2 workaround state to KVM guestsAndre Przywara
Recent commits added the explicit notion of "workaround not required" to the state of the Spectre v2 (aka. BP_HARDENING) workaround, where we just had "needed" and "unknown" before. Export this knowledge to the rest of the kernel and enhance the existing kvm_arm_harden_branch_predictor() to report this new state as well. Export this new state to guests when they use KVM's firmware interface emulation. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Steven Price <steven.price@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm/arm64: Support chained PMU countersAndrew Murray
ARMv8 provides support for chained PMU counters, where an event type of 0x001E is set for odd-numbered counters, the event counter will increment by one for each overflow of the preceding even-numbered counter. Let's emulate this in KVM by creating a 64 bit perf counter when a user chains two emulated counters together. For chained events we only support generating an overflow interrupt on the high counter. We use the attributes of the low counter to determine the attributes of the perf event. Suggested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm/arm64: Remove pmc->bitmaskAndrew Murray
We currently use pmc->bitmask to determine the width of the pmc - however it's superfluous as the pmc index already describes if the pmc is a cycle counter or event counter. The architecture clearly describes the widths of these counters. Let's remove the bitmask to simplify the code. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm/arm64: Re-create event when setting counter valueAndrew Murray
The perf event sample_period is currently set based upon the current counter value, when PMXEVTYPER is written to and the perf event is created. However the user may choose to write the type before the counter value in which case sample_period will be set incorrectly. Let's instead decouple event creation from PMXEVTYPER and (re)create the event in either suitation. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm/arm64: Extract duplicated code to own functionAndrew Murray
Let's reduce code duplication by extracting common code to its own function. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-07-05KVM: arm/arm64: Rename kvm_pmu_{enable/disable}_counter functionsAndrew Murray
The kvm_pmu_{enable/disable}_counter functions can enable/disable multiple counters at once as they operate on a bitmask. Let's make this clearer by renaming the function. Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Andrew Murray <andrew.murray@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-21Merge tag 'spdx-5.2-rc6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx Pull still more SPDX updates from Greg KH: "Another round of SPDX updates for 5.2-rc6 Here is what I am guessing is going to be the last "big" SPDX update for 5.2. It contains all of the remaining GPLv2 and GPLv2+ updates that were "easy" to determine by pattern matching. The ones after this are going to be a bit more difficult and the people on the spdx list will be discussing them on a case-by-case basis now. Another 5000+ files are fixed up, so our overall totals are: Files checked: 64545 Files with SPDX: 45529 Compared to the 5.1 kernel which was: Files checked: 63848 Files with SPDX: 22576 This is a huge improvement. Also, we deleted another 20000 lines of boilerplate license crud, always nice to see in a diffstat" * tag 'spdx-5.2-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx: (65 commits) treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 507 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 506 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 505 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 504 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 503 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 502 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 501 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 498 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 497 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 496 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 495 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 491 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 490 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 489 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 488 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 487 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 486 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 485 ...
2019-06-20Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "Fixes for ARM and x86, plus selftest patches and nicer structs for nested state save/restore" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: nVMX: reorganize initial steps of vmx_set_nested_state KVM: arm/arm64: Fix emulated ptimer irq injection tests: kvm: Check for a kernel warning kvm: tests: Sort tests in the Makefile alphabetically KVM: x86/mmu: Allocate PAE root array when using SVM's 32-bit NPT KVM: x86: Modify struct kvm_nested_state to have explicit fields for data KVM: fix typo in documentation KVM: nVMX: use correct clean fields when copying from eVMCS KVM: arm/arm64: vgic: Fix kvm_device leak in vgic_its_destroy KVM: arm64: Filter out invalid core register IDs in KVM_GET_REG_LIST KVM: arm64: Implement vq_present() as a macro
2019-06-20Merge tag 'kvmarm-fixes-for-5.2-2' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm fixes for 5.2, take #2 - SVE cleanup killing a warning with ancient GCC versions - Don't report non-existent system registers to userspace - Fix memory leak when freeing the vgic ITS - Properly lower the interrupt on the emulated physical timer
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 504Thomas Gleixner
Based on 1 normalized pattern(s): this file is free software you can redistribute it and or modify it under the terms of version 2 of the gnu general public license as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin st fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 8 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081207.443595178@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499Thomas Gleixner
Based on 1 normalized pattern(s): this work is licensed under the terms of the gnu gpl version 2 see the copying file in the top level directory extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 35 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.797835076@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19KVM: arm/arm64: Fix emulated ptimer irq injectionAndrew Jones
The emulated ptimer needs to track the level changes, otherwise the the interrupt will never get deasserted, resulting in the guest getting stuck in an interrupt storm if it enables ptimer interrupts. This was found with kvm-unit-tests; the ptimer tests hung as soon as interrupts were enabled. Typical Linux guests don't have a problem as they prefer using the virtual timer. Fixes: bee038a674875 ("KVM: arm/arm64: Rework the timer code to use a timer_map") Signed-off-by: Andrew Jones <drjones@redhat.com> [Simplified the patch to res we only care about emulated timers here] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-12KVM: arm/arm64: vgic: Fix kvm_device leak in vgic_its_destroyDave Martin
kvm_device->destroy() seems to be supposed to free its kvm_device struct, but vgic_its_destroy() is not currently doing this, resulting in a memory leak, resulting in kmemleak reports such as the following: unreferenced object 0xffff800aeddfe280 (size 128): comm "qemu-system-aar", pid 13799, jiffies 4299827317 (age 1569.844s) [...] backtrace: [<00000000a08b80e2>] kmem_cache_alloc+0x178/0x208 [<00000000dcad2bd3>] kvm_vm_ioctl+0x350/0xbc0 Fix it. Cc: Andre Przywara <andre.przywara@arm.com> Fixes: 1085fdc68c60 ("KVM: arm64: vgic-its: Introduce new KVM ITS device") Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 136 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000436.384967451@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 320Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms and conditions of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 33 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000435.254582722@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 67 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141333.953658117@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05kvm: Convert kvm_lock to a mutexJunaid Shahid
It doesn't seem as if there is any particular need for kvm_lock to be a spinlock, so convert the lock to a mutex so that sleepable functions (in particular cond_resched()) can be called while holding it. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-05KVM: irqchip: Use struct_size() in kzalloc()Gustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; struct boo entry[]; }; instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-04KVM: Directly return result from kvm_arch_check_processor_compat()Sean Christopherson
Add a wrapper to invoke kvm_arch_check_processor_compat() so that the boilerplate ugliness of checking virtualization support on all CPUs is hidden from the arch specific code. x86's implementation in particular is quite heinous, as it unnecessarily propagates the out-param pattern into kvm_x86_ops. While the x86 specific issue could be resolved solely by changing kvm_x86_ops, make the change for all architectures as returning a value directly is prettier and technically more robust, e.g. s390 doesn't set the out param, which could lead to subtle breakage in the (highly unlikely) scenario where the out-param was not pre-initialized by the caller. Opportunistically annotate svm_check_processor_compat() with __init. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2019-06-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "Fixes for PPC and s390" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: PPC: Book3S HV: Restore SPRG3 in kvmhv_p9_guest_entry() KVM: PPC: Book3S HV: Fix lockdep warning when entering guest on POWER9 KVM: PPC: Book3S HV: XIVE: Fix page offset when clearing ESB pages KVM: PPC: Book3S HV: XIVE: Take the srcu read lock when accessing memslots KVM: PPC: Book3S HV: XIVE: Do not clear IRQ data of passthrough interrupts KVM: PPC: Book3S HV: XIVE: Introduce a new mutex for the XIVE device KVM: PPC: Book3S HV: XIVE: Fix the enforced limit on the vCPU identifier KVM: PPC: Book3S HV: XIVE: Do not test the EQ flag validity when resetting KVM: PPC: Book3S HV: XIVE: Clear file mapping when device is released KVM: PPC: Book3S HV: Don't take kvm->lock around kvm_for_each_vcpu KVM: PPC: Book3S: Use new mutex to synchronize access to rtas token list KVM: PPC: Book3S HV: Use new mutex to synchronize MMU setup KVM: PPC: Book3S HV: Avoid touching arch.mmu_ready in XIVE release functions KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID kvm: fix compile on s390 part 2
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-28KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_IDThomas Huth
KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all architectures. However, on s390x, the amount of usable CPUs is determined during runtime - it is depending on the features of the machine the code is running on. Since we are using the vcpu_id as an index into the SCA structures that are defined by the hardware (see e.g. the sca_add_vcpu() function), it is not only the amount of CPUs that is limited by the hard- ware, but also the range of IDs that we can use. Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too. So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common code into the architecture specific code, and on s390x we have to return the same value here as for KVM_CAP_MAX_VCPUS. This problem has been discovered with the kvm_create_max_vcpus selftest. With this change applied, the selftest now passes on s390x, too. Reviewed-by: Andrew Jones <drjones@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <20190523164309.13345-9-thuth@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>