linux/virt/kvm, branch v4.2

KVM: count number of assigned devices

2015-07-10T11:25:26Z

If there are no assigned devices, the guest PAT are not providing any useful information and can be overridden to writeback; VMX always does this because it has the "IPAT" bit in its extended page table entries, but SVM does not have anything similar. Hook into VFIO and legacy device assignment so that they provide this information to KVM. Reviewed-by: Alex Williamson Tested-by: Joerg Roedel Signed-off-by: Paolo Bonzini

sched, preempt_notifier: separate notifier registration from static_key inc/dec

2015-07-03T16:55:00Z

Commit 1cde2930e154 ("sched/preempt: Add static_key() to preempt_notifiers") had two problems. First, the preempt-notifier API needs to sleep with the addition of the static_key, we do however need to hold off preemption while modifying the preempt notifier list, otherwise a preemption could observe an inconsistent list state. KVM correctly registers and unregisters preempt notifiers with preemption disabled, so the sleep caused dmesg splats. Second, KVM registers and unregisters preemption notifiers very often (in vcpu_load/vcpu_put). With a single uniprocessor guest the static key would move between 0 and 1 continuously, hitting the slow path on every userspace exit. To fix this, wrap the static_key inc/dec in a new API, and call it from KVM. Fixes: 1cde2930e154 ("sched/preempt: Add static_key() to preempt_notifiers") Reported-by: Pontus Fuchs Reported-by: Takashi Iwai Tested-by: Takashi Iwai Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Paolo Bonzini

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

2015-06-24T17:02:15Z

Pull arm64 updates from Catalin Marinas: "Mostly refactoring/clean-up: - CPU ops and PSCI (Power State Coordination Interface) refactoring following the merging of the arm64 ACPI support, together with handling of Trusted (secure) OS instances - Using fixmap for permanent FDT mapping, removing the initial dtb placement requirements (within 512MB from the start of the kernel image). This required moving the FDT self reservation out of the memreserve processing - Idmap (1:1 mapping used for MMU on/off) handling clean-up - Removing flush_cache_all() - not safe on ARM unless the MMU is off. Last stages of CPU power down/up are handled by firmware already - "Alternatives" (run-time code patching) refactoring and support for immediate branch patching, GICv3 CPU interface access - User faults handling clean-up And some fixes: - Fix for VDSO building with broken ELF toolchains - Fix another case of init_mm.pgd usage for user mappings (during ASID roll-over broadcasting) - Fix for FPSIMD reloading after CPU hotplug - Fix for missing syscall trace exit - Workaround for .inst asm bug - Compat fix for switching the user tls tpidr_el0 register" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (42 commits) arm64: use private ratelimit state along with show_unhandled_signals arm64: show unhandled SP/PC alignment faults arm64: vdso: work-around broken ELF toolchains in Makefile arm64: kernel: rename __cpu_suspend to keep it aligned with arm arm64: compat: print compat_sp instead of sp arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP arm64: entry: fix context tracking for el0_sp_pc arm64: defconfig: enable memtest arm64: mm: remove reference to tlb.S from comment block arm64: Do not attempt to use init_mm in reset_context() arm64: KVM: Switch vgic save/restore to alternative_insn arm64: alternative: Introduce feature for GICv3 CPU interface arm64: psci: fix !CONFIG_HOTPLUG_CPU build warning arm64: fix bug for reloading FPSIMD state after CPU hotplug. arm64: kernel thread don't need to save fpsimd context. arm64: fix missing syscall trace exit arm64: alternative: Work around .inst assembler bugs arm64: alternative: Merge alternative-asm.h into alternative.h arm64: alternative: Allow immediate branch as alternative instruction arm64: Rework alternate sequence for ARM erratum 845719 ...

KVM: fix checkpatch.pl errors in kvm/coalesced_mmio.h

2015-06-19T15:16:26Z

Tabs rather than spaces Signed-off-by: Kevin Mulvey Signed-off-by: Paolo Bonzini

KVM: fix checkpatch.pl errors in kvm/async_pf.h

2015-06-19T15:16:25Z

fix brace spacing Signed-off-by: Kevin Mulvey Signed-off-by: Paolo Bonzini

kvm: irqchip: Break up high order allocations of kvm_irq_routing_table

2015-06-19T15:16:25Z

The allocation size of the kvm_irq_routing_table depends on the number of irq routing entries because they are all allocated with one kzalloc call. When the irq routing table gets bigger this requires high order allocations which fail from time to time: qemu-kvm: page allocation failure: order:4, mode:0xd0 This patch fixes this issue by breaking up the allocation of the table and its entries into individual kzalloc calls. These could all be satisfied with order-0 allocations, which are less likely to fail. The downside of this change is the lower performance, because of more calls to kzalloc. But given how often kvm_set_irq_routing is called in the lifetime of a guest, it doesn't really matter much. Signed-off-by: Joerg Roedel [Avoid sparse warning through rcu_access_pointer. - Paolo] Signed-off-by: Paolo Bonzini

Merge tag 'kvm-arm-for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2015-06-19T15:15:24Z

KVM/ARM changes for v4.2: - Proper guest time accounting - FP access fix for 32bit - The usual pile of GIC fixes - PSCI fixes - Random cleanups

KVM: arm/arm64: vgic: Remove useless arm-gic.h #include

2015-06-18T14:50:31Z

Back in the days, vgic.c used to have an intimate knowledge of the actual GICv2. These days, this has been abstracted away into hardware-specific backends. Remove the now useless arm-gic.h #include directive, making it clear that GICv2 specific code doesn't belong here. Signed-off-by: Marc Zyngier

KVM: arm/arm64: vgic: Avoid injecting reserved IRQ numbers

2015-06-17T14:18:59Z

Commit fd1d0ddf2ae9 (KVM: arm/arm64: check IRQ number on userland injection) rightly limited the range of interrupts userspace can inject in a guest, but failed to consider the (unlikely) case where a guest is configured with 1024 interrupts. In this case, interrupts ranging from 1020 to 1023 are unuseable, as they have a special meaning for the GIC CPU interface. Make sure that these number cannot be used as an IRQ. Also delete a redundant (and similarily buggy) check in kvm_set_irq. Reported-by: Peter Maydell Cc: Andre Przywara Cc: # 4.1, 4.0, 3.19, 3.18 Signed-off-by: Marc Zyngier

KVM: arm: vgic: Drop useless Group0 warning

2015-06-17T08:58:12Z

If a GICv3-enabled guest tries to configure Group0, we print a warning on the console (because we don't support Group0 interrupts). This is fairly pointless, and would allow a guest to spam the console. Let's just drop the warning. Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier