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2018-01-02KVM: arm/arm64: Support a vgic interrupt line level sample functionChristoffer Dall2-5/+11
The GIC sometimes need to sample the physical line of a mapped interrupt. As we know this to be notoriously slow, provide a callback function for devices (such as the timer) which can do this much faster than talking to the distributor, for example by comparing a few in-memory values. Fall back to the good old method of poking the physical GIC if no callback is provided. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02KVM: arm/arm64: vgic: Support level-triggered mapped interruptsChristoffer Dall4-0/+88
Level-triggered mapped IRQs are special because we only observe rising edges as input to the VGIC, and we don't set the EOI flag and therefore are not told when the level goes down, so that we can re-queue a new interrupt when the level goes up. One way to solve this problem is to side-step the logic of the VGIC and special case the validation in the injection path, but it has the unfortunate drawback of having to peak into the physical GIC state whenever we want to know if the interrupt is pending on the virtual distributor. Instead, we can maintain the current semantics of a level triggered interrupt by sort of treating it as an edge-triggered interrupt, following from the fact that we only observe an asserting edge. This requires us to be a bit careful when populating the LRs and when folding the state back in though: * We lower the line level when populating the LR, so that when subsequently observing an asserting edge, the VGIC will do the right thing. * If the guest never acked the interrupt while running (for example if it had masked interrupts at the CPU level while running), we have to preserve the pending state of the LR and move it back to the line_level field of the struct irq when folding LR state. If the guest never acked the interrupt while running, but changed the device state and lowered the line (again with interrupts masked) then we need to observe this change in the line_level. Both of the above situations are solved by sampling the physical line and set the line level when folding the LR back. * Finally, if the guest never acked the interrupt while running and sampling the line reveals that the device state has changed and the line has been lowered, we must clear the physical active state, since we will otherwise never be told when the interrupt becomes asserted again. This has the added benefit of making the timer optimization patches (https://lists.cs.columbia.edu/pipermail/kvmarm/2017-July/026343.html) a bit simpler, because the timer code doesn't have to clear the active state on the sync anymore. It also potentially improves the performance of the timer implementation because the GIC knows the state or the LR and only needs to clear the active state when the pending bit in the LR is still set, where the timer has to always clear it when returning from running the guest with an injected timer interrupt. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02KVM: arm/arm64: Don't cache the timer IRQ levelChristoffer Dall1-7/+13
The timer logic was designed after a strict idea of modeling an interrupt line level in software, meaning that only transitions in the level need to be reported to the VGIC. This works well for the timer, because the arch timer code is in complete control of the device and can track the transitions of the line. However, as we are about to support using the HW bit in the VGIC not just for the timer, but also for VFIO which cannot track transitions of the interrupt line, we have to decide on an interface between the GIC and other subsystems for level triggered mapped interrupts, which both the timer and VFIO can use. VFIO only sees an asserting transition of the physical interrupt line, and tells the VGIC when that happens. That means that part of the interrupt flow is offloaded to the hardware. To use the same interface for VFIO devices and the timer, we therefore have to change the timer (we cannot change VFIO because it doesn't know the details of the device it is assigning to a VM). Luckily, changing the timer is simple, we just need to stop 'caching' the line level, but instead let the VGIC know the state of the timer every time there is a potential change in the line level, and when the line level should be asserted from the timer ISR. The VGIC can ignore extra notifications using its validate mechanism. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Julien Thierry <julien.thierry@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02KVM: arm/arm64: Factor out functionality to get vgic mmio requester_vcpuChristoffer Dall1-16/+28
We are about to distinguish between userspace accesses and mmio traps for a number of the mmio handlers. When the requester vcpu is NULL, it means we are handling a userspace access. Factor out the functionality to get the request vcpu into its own function, mostly so we have a common place to document the semantics of the return value. Also take the chance to move the functionality outside of holding a spinlock and instead explicitly disable and enable preemption. This supports PREEMPT_RT kernels as well. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02KVM: arm/arm64: Remove redundant preemptible checksChristoffer Dall1-2/+0
The __this_cpu_read() and __this_cpu_write() functions already implement checks for the required preemption levels when using CONFIG_DEBUG_PREEMPT which gives you nice error messages and such. Therefore there is no need to explicitly check this using a BUG_ON() in the code (which we don't do for other uses of per cpu variables either). Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-01-02KVM: arm: Use PTR_ERR_OR_ZERO()Vasyl Gomonovych1-3/+1
Fix ptr_ret.cocci warnings: virt/kvm/arm/vgic/vgic-its.c:971:1-3: WARNING: PTR_ERR_OR_ZERO can be used Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR Generated by: scripts/coccinelle/api/ptr_ret.cocci Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-22arm64: allow ID map to be extended to 52 bitsKristina Martsenko1-2/+8
Currently, when using VA_BITS < 48, if the ID map text happens to be placed in physical memory above VA_BITS, we increase the VA size (up to 48) and create a new table level, in order to map in the ID map text. This is okay because the system always supports 48 bits of VA. This patch extends the code such that if the system supports 52 bits of VA, and the ID map text is placed that high up, then we increase the VA size accordingly, up to 52. One difference from the current implementation is that so far the condition of VA_BITS < 48 has meant that the top level table is always "full", with the maximum number of entries, and an extra table level is always needed. Now, when VA_BITS = 48 (and using 64k pages), the top level table is not full, and we simply need to increase the number of entries in it, instead of creating a new table level. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()] [catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22arm64: handle 52-bit addresses in TTBRKristina Martsenko1-1/+1
The top 4 bits of a 52-bit physical address are positioned at bits 2..5 in the TTBR registers. Introduce a couple of macros to move the bits there, and change all TTBR writers to use them. Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with 52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a system without 52-bit PA can only use up to 48-bit PAs. A later patch in this series will add a kconfig dependency to ensure PAN is configured. In addition, when using 52-bit PA there is a special alignment requirement on the top-level table. We don't currently have any VA_BITS configuration that would violate the requirement, but one could be added in the future, so add a compile-time BUG_ON to check for it. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-18Merge tag 'kvm-arm-fixes-for-v4.15-2' of ↵Paolo Bonzini3-23/+29
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/ARM Fixes for v4.15, Round 2 Fixes: - A bug in our handling of SPE state for non-vhe systems - A bug that causes hyp unmapping to go off limits and crash the system on shutdown - Three timer fixes that were introduced as part of the timer optimizations for v4.15
2017-12-18KVM: Fix stack-out-of-bounds read in write_mmioWanpeng Li1-3/+3
Reported by syzkaller: BUG: KASAN: stack-out-of-bounds in write_mmio+0x11e/0x270 [kvm] Read of size 8 at addr ffff8803259df7f8 by task syz-executor/32298 CPU: 6 PID: 32298 Comm: syz-executor Tainted: G OE 4.15.0-rc2+ #18 Hardware name: LENOVO ThinkCentre M8500t-N000/SHARKBAY, BIOS FBKTC1AUS 02/16/2016 Call Trace: dump_stack+0xab/0xe1 print_address_description+0x6b/0x290 kasan_report+0x28a/0x370 write_mmio+0x11e/0x270 [kvm] emulator_read_write_onepage+0x311/0x600 [kvm] emulator_read_write+0xef/0x240 [kvm] emulator_fix_hypercall+0x105/0x150 [kvm] em_hypercall+0x2b/0x80 [kvm] x86_emulate_insn+0x2b1/0x1640 [kvm] x86_emulate_instruction+0x39a/0xb90 [kvm] handle_exception+0x1b4/0x4d0 [kvm_intel] vcpu_enter_guest+0x15a0/0x2640 [kvm] kvm_arch_vcpu_ioctl_run+0x549/0x7d0 [kvm] kvm_vcpu_ioctl+0x479/0x880 [kvm] do_vfs_ioctl+0x142/0x9a0 SyS_ioctl+0x74/0x80 entry_SYSCALL_64_fastpath+0x23/0x9a The path of patched vmmcall will patch 3 bytes opcode 0F 01 C1(vmcall) to the guest memory, however, write_mmio tracepoint always prints 8 bytes through *(u64 *)val since kvm splits the mmio access into 8 bytes. This leaks 5 bytes from the kernel stack (CVE-2017-17741). This patch fixes it by just accessing the bytes which we operate on. Before patch: syz-executor-5567 [007] .... 51370.561696: kvm_mmio: mmio write len 3 gpa 0x10 val 0x1ffff10077c1010f After patch: syz-executor-13416 [002] .... 51302.299573: kvm_mmio: mmio write len 3 gpa 0x10 val 0xc1010f Reported-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-18KVM: arm/arm64: Fix timer enable flowChristoffer Dall1-4/+1
When enabling the timer on the first run, we fail to ever restore the state and mark it as loaded. That means, that in the initial entry to the VCPU ioctl, unless we exit to userspace for some reason such as a pending signal, if the guest programs a timer and blocks, we will wait forever, because we never read back the hardware state (the loaded flag is not set), and so we think the timer is disabled, and we never schedule a background soft timer. The end result? The VCPU blocks forever, and the only solution is to kill the thread. Fixes: 4a2c4da1250d ("arm/arm64: KVM: Load the timer state when enabling the timer") Reported-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-18KVM: arm/arm64: Properly handle arch-timer IRQs after vtimer_save_stateChristoffer Dall1-7/+15
The recent timer rework was assuming that once the timer was disabled, we should no longer see any interrupts from the timer. This assumption turns out to not be true, and instead we have to handle the case when the timer ISR runs even after the timer has been disabled. This requires a couple of changes: First, we should never overwrite the cached guest state of the timer control register when the ISR runs, because KVM may have disabled its timers when doing vcpu_put(), even though the guest still had the timer enabled. Second, we shouldn't assume that the timer is actually firing just because we see an interrupt, but we should check the actual state of the timer in the timer control register to understand if the hardware timer is really firing or not. We also add an ISB to vtimer_save_state() to ensure the timer is actually disabled once we enable interrupts, which should clarify the intention of the implementation, and reduce the risk of unwanted interrupts. Fixes: b103cc3f10c0 ("KVM: arm/arm64: Avoid timer save/restore in vcpu entry/exit") Reported-by: Marc Zyngier <marc.zyngier@arm.com> Reported-by: Jia He <hejianet@gmail.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-18KVM: arm/arm64: timer: Don't set irq as forwarded if no usable GICMarc Zyngier2-6/+9
If we don't have a usable GIC, do not try to set the vcpu affinity as this is guaranteed to fail. Reported-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-18KVM: arm/arm64: Fix HYP unmapping going off limitsMarc Zyngier1-6/+4
When we unmap the HYP memory, we try to be clever and unmap one PGD at a time. If we start with a non-PGD aligned address and try to unmap a whole PGD, things go horribly wrong in unmap_hyp_range (addr and end can never match, and it all goes really badly as we keep incrementing pgd and parse random memory as page tables...). The obvious fix is to let unmap_hyp_range do what it does best, which is to iterate over a range. The size of the linear mapping, which begins at PAGE_OFFSET, can be easily calculated by subtracting PAGE_OFFSET form high_memory, because high_memory is defined as the linear map address of the last byte of DRAM, plus one. The size of the vmalloc region is given trivially by VMALLOC_END - VMALLOC_START. Cc: stable@vger.kernel.org Reported-by: Andre Przywara <andre.przywara@arm.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-14KVM: introduce kvm_arch_vcpu_async_ioctlPaolo Bonzini2-7/+8
After the vcpu_load/vcpu_put pushdown, the handling of asynchronous VCPU ioctl is already much clearer in that it is obvious that they bypass vcpu_load and vcpu_put. However, it is still not perfect in that the different state of the VCPU mutex is still hidden in the caller. Separate those ioctls into a new function kvm_arch_vcpu_async_ioctl that returns -ENOIOCTLCMD for more "traditional" synchronous ioctls. Cc: James Hogan <jhogan@kernel.org> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Suggested-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctlChristoffer Dall2-20/+40
Move the calls to vcpu_load() and vcpu_put() in to the architecture specific implementations of kvm_arch_vcpu_ioctl() which dispatches further architecture-specific ioctls on to other functions. Some architectures support asynchronous vcpu ioctls which cannot call vcpu_load() or take the vcpu->mutex, because that would prevent concurrent execution with a running VCPU, which is the intended purpose of these ioctls, for example because they inject interrupts. We repeat the separate checks for these specifics in the architecture code for MIPS, S390 and PPC, and avoid taking the vcpu->mutex and calling vcpu_load for these ioctls. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_set_fpuChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_set_fpu(). Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_get_fpuChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_get_fpu(). Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_set_guest_debugChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_set_guest_debug(). Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_translateChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_translate(). Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_set_mpstateChristoffer Dall2-4/+7
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_set_mpstate(). Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_get_mpstateChristoffer Dall2-2/+3
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_get_mpstate(). Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_set_sregsChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_set_sregs(). Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_get_sregsChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_get_sregs(). Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_set_regsChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_set_regs(). Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_get_regsChristoffer Dall1-2/+0
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_get_regs(). Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Move vcpu_load to arch-specific kvm_arch_vcpu_ioctl_runChristoffer Dall2-8/+14
Move vcpu_load() and vcpu_put() into the architecture specific implementations of kvm_arch_vcpu_ioctl_run(). Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> # s390 parts Reviewed-by: Cornelia Huck <cohuck@redhat.com> [Rebased. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Prepare for moving vcpu_load/vcpu_put into arch specific codeChristoffer Dall1-2/+24
In preparation for moving calls to vcpu_load() and vcpu_put() into the architecture specific implementations of the KVM vcpu ioctls, move the calls in the main kvm_vcpu_ioctl() dispatcher function to each case of the ioctl select statement. This allows us to move the vcpu_load() and vcpu_put() calls into architecture specific implementations of vcpu ioctls, one by one. Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14KVM: Take vcpu->mutex outside vcpu_loadChristoffer Dall1-11/+6
As we're about to call vcpu_load() from architecture-specific implementations of the KVM vcpu ioctls, but yet we access data structures protected by the vcpu->mutex in the generic code, factor this logic out from vcpu_load(). x86 is the only architecture which calls vcpu_load() outside of the main vcpu ioctl function, and these calls will no longer take the vcpu mutex following this patch. However, with the exception of kvm_arch_vcpu_postcreate (see below), the callers are either in the creation or destruction path of the VCPU, which means there cannot be any concurrent access to the data structure, because the file descriptor is not yet accessible, or is already gone. kvm_arch_vcpu_postcreate makes the newly created vcpu potentially accessible by other in-kernel threads through the kvm->vcpus array, and we therefore take the vcpu mutex in this case directly. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14kvm_main: Use common error handling code in kvm_dev_ioctl_create_vm()Markus Elfring1-10/+11
Add a jump target so that a bit of exception handling can be better reused at the end of this function. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-12-06KVM: x86: fix APIC page invalidationRadim Krčmář1-0/+8
Implementation of the unpinned APIC page didn't update the VMCS address cache when invalidation was done through range mmu notifiers. This became a problem when the page notifier was removed. Re-introduce the arch-specific helper and call it from ...range_start. Reported-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> Fixes: 38b9917350cb ("kvm: vmx: Implement set_apic_access_page_addr") Fixes: 369ea8242c0f ("mm/rmap: update to new mmu_notifier semantic v2") Cc: <stable@vger.kernel.org> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Tested-by: Wanpeng Li <wanpeng.li@hotmail.com> Tested-by: Fabian Grünbichler <f.gruenbichler@proxmox.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-12-05Merge tag 'kvm-arm-fixes-for-v4.15-1' of ↵Radim Krčmář9-50/+43
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm KVM/ARM Fixes for v4.15. Fixes: - A number of issues in the vgic discovered using SMATCH - A bit one-off calculation in out stage base address mask (32-bit and 64-bit) - Fixes to single-step debugging instructions that trap for other reasons such as MMMIO aborts - Printing unavailable hyp mode as error - Potential spinlock deadlock in the vgic - Avoid calling vgic vcpu free more than once - Broken bit calculation for big endian systems
2017-12-04kvm: switch get_user_page_nowait() to get_user_pages_unlocked()Al Viro1-31/+12
... and fold into the sole caller, unifying async and non-async cases Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-12-04KVM: arm/arm64: Fix broken GICH_ELRSR big endian conversionChristoffer Dall1-4/+0
We are incorrectly rearranging 32-bit words inside a 64-bit typed value for big endian systems, which would result in never marking a virtual interrupt as inactive on big endian systems (assuming 32 or fewer LRs on the hardware). Fix this by not doing any word order manipulation for the typed values. Cc: <stable@vger.kernel.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-01KVM: arm/arm64: kvm_arch_destroy_vm cleanupsAndrew Jones1-1/+1
kvm_vgic_vcpu_destroy already gets called from kvm_vgic_destroy for each vcpu, so we don't have to call it from kvm_arch_vcpu_free. Additionally the other architectures set kvm->online_vcpus to zero after freeing them. We might as well do that for ARM too. Signed-off-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-12-01KVM: arm/arm64: Fix spinlock acquisition in vgic_set_ownerMarc Zyngier1-2/+3
vgic_set_owner acquires the irq lock without disabling interrupts, resulting in a lockdep splat (an interrupt could fire and result in the same lock being taken if the same virtual irq is to be injected). In practice, it is almost impossible to trigger this bug, but better safe than sorry. Convert the lock acquisition to a spin_lock_irqsave() and keep lockdep happy. Reported-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-30Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2-5/+26
Pull KVM fixes from Paolo Bonzini: - x86 bugfixes: APIC, nested virtualization, IOAPIC - PPC bugfix: HPT guests on a POWER9 radix host * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (26 commits) KVM: Let KVM_SET_SIGNAL_MASK work as advertised KVM: VMX: Fix vmx->nested freeing when no SMI handler KVM: VMX: Fix rflags cache during vCPU reset KVM: X86: Fix softlockup when get the current kvmclock KVM: lapic: Fixup LDR on load in x2apic KVM: lapic: Split out x2apic ldr calculation KVM: PPC: Book3S HV: Fix migration and HPT resizing of HPT guests on radix hosts KVM: vmx: use X86_CR4_UMIP and X86_FEATURE_UMIP KVM: x86: Fix CPUID function for word 6 (80000001_ECX) KVM: nVMX: Fix vmx_check_nested_events() return value in case an event was reinjected to L2 KVM: x86: ioapic: Preserve read-only values in the redirection table KVM: x86: ioapic: Clear Remote IRR when entry is switched to edge-triggered KVM: x86: ioapic: Remove redundant check for Remote IRR in ioapic_set_irq KVM: x86: ioapic: Don't fire level irq when Remote IRR set KVM: x86: ioapic: Fix level-triggered EOI and IOAPIC reconfigure race KVM: x86: inject exceptions produced by x86_decode_insn KVM: x86: Allow suppressing prints on RDMSR/WRMSR of unhandled MSRs KVM: x86: fix em_fxstor() sleeping while in atomic KVM: nVMX: Fix mmu context after VMLAUNCH/VMRESUME failure KVM: nVMX: Validate the IA32_BNDCFGS on nested VM-entry ...
2017-11-29kvm: arm: don't treat unavailable HYP mode as an errorArd Biesheuvel1-1/+1
Since it is perfectly legal to run the kernel at EL1, it is not actually an error if HYP mode is not available when attempting to initialize KVM, given that KVM support cannot be built as a module. So demote the kvm_err() to kvm_info(), which prevents the error from appearing on an otherwise 'quiet' console. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: Avoid attempting to load timer vgic state without a vgicChristoffer Dall1-1/+4
The timer optimization patches inadvertendly changed the logic to always load the timer state as if we have a vgic, even if we don't have a vgic. Fix this by doing the usual irqchip_in_kernel() check and call the appropriate load function. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29kvm: arm64: handle single-step of userspace mmio instructionsAlex Bennée1-0/+3
The system state of KVM when using userspace emulation is not complete until we return into KVM_RUN. To handle mmio related updates we wait until they have been committed and then schedule our KVM_EXIT_DEBUG. The kvm_arm_handle_step_debug() helper tells us if we need to return and sets up the exit_reason for us. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: vgic-v4: Only perform an unmap for valid vLPIsMarc Zyngier1-2/+4
Before performing an unmap, let's check that what we have was really mapped the first place. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: vgic-its: Check result of allocation before useMarc Zyngier1-0/+2
We miss a test against NULL after allocation. Fixes: 6d03a68f8054 ("KVM: arm64: vgic-its: Turn device_id validation into generic ID validation") Cc: stable@vger.kernel.org # 4.8 Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: vgic-its: Preserve the revious read from the pending tableMarc Zyngier1-1/+1
The current pending table parsing code assumes that we keep the previous read of the pending bits, but keep that variable in the current block, making sure it is discarded on each loop. We end-up using whatever is on the stack. Who knows, it might just be the right thing... Fixes: 33d3bc9556a7d ("KVM: arm64: vgic-its: Read initial LPI pending table") Cc: stable@vger.kernel.org # 4.8 Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: vgic: Preserve the revious read from the pending tableMarc Zyngier1-1/+1
The current pending table parsing code assumes that we keep the previous read of the pending bits, but keep that variable in the current block, making sure it is discarded on each loop. We end-up using whatever is on the stack. Who knows, it might just be the right thing... Fixes: 280771252c1ba ("KVM: arm64: vgic-v3: KVM_DEV_ARM_VGIC_SAVE_PENDING_TABLES") Cc: stable@vger.kernel.org # 4.12 Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: vgic-irqfd: Fix MSI entry allocationMarc Zyngier1-2/+1
Using the size of the structure we're allocating is a good idea and avoids any surprise... In this case, we're happilly confusing kvm_kernel_irq_routing_entry and kvm_irq_routing_entry... Fixes: 95b110ab9a09 ("KVM: arm/arm64: Enable irqchip routing") Cc: stable@vger.kernel.org # 4.8 Reported-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: VGIC: extend !vgic_is_initialized guardAndre Przywara1-1/+2
Commit f39d16cbabf9 ("KVM: arm/arm64: Guard kvm_vgic_map_is_active against !vgic_initialized") introduced a check whether the VGIC has been initialized before accessing the spinlock and the VGIC data structure. However the vgic_get_irq() call in the variable declaration sneaked through the net, so lets make sure that this also gets called only after we actually allocated the arrays this function accesses. Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-29KVM: arm/arm64: Don't enable/disable physical timer access on VHEChristoffer Dall2-34/+20
After the timer optimization rework we accidentally end up calling physical timer enable/disable functions on VHE systems, which is neither needed nor correct, since the CNTHCTL_EL2 register format is different when HCR_EL2.E2H is set. The CNTHCTL_EL2 is initialized when CPUs become online in kvm_timer_init_vhe() and we don't have to call these functions on VHE systems, which also allows us to inline the non-VHE functionality. Reported-by: Jintack Lim <jintack@cs.columbia.edu> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-11-27annotate poll-related wait keysAl Viro1-1/+1
__poll_t is also used as wait key in some waitqueues. Verify that wait_..._poll() gets __poll_t as key and provide a helper for wakeup functions to get back to that __poll_t value. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27anntotate the places where ->poll() return values goAl Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27KVM: Let KVM_SET_SIGNAL_MASK work as advertisedJan H. Schönherr2-5/+26
KVM API says for the signal mask you set via KVM_SET_SIGNAL_MASK, that "any unblocked signal received [...] will cause KVM_RUN to return with -EINTR" and that "the signal will only be delivered if not blocked by the original signal mask". This, however, is only true, when the calling task has a signal handler registered for a signal. If not, signal evaluation is short-circuited for SIG_IGN and SIG_DFL, and the signal is either ignored without KVM_RUN returning or the whole process is terminated. Make KVM_SET_SIGNAL_MASK behave as advertised by utilizing logic similar to that in do_sigtimedwait() to avoid short-circuiting of signals. Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>