kernel/linux.git/virt/kvm/arm, branch v4.9.136

KVM: arm/arm64: Fix vgic init race

2018-09-26T06:36:34+00:00

[ Upstream commit 1d47191de7e15900f8fbfe7cccd7c6e1c2d7c31a ] The vgic_init function can race with kvm_arch_vcpu_create() which does not hold kvm_lock() and we therefore have no synchronization primitives to ensure we're doing the right thing. As the user is trying to initialize or run the VM while at the same time creating more VCPUs, we just have to refuse to initialize the VGIC in this case rather than silently failing with a broken VCPU. Reviewed-by: Eric Auger Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: Drop resource size check for GICV window

2018-08-24T11:12:30+00:00

[ Upstream commit ba56bc3a0786992755e6804fbcbdc60ef6cfc24c ] When booting a 64 KB pages kernel on a ACPI GICv3 system that implements support for v2 emulation, the following warning is produced GICV size 0x2000 not a multiple of page size 0x10000 and support for v2 emulation is disabled, preventing GICv2 VMs from being able to run on such hosts. The reason is that vgic_v3_probe() performs a sanity check on the size of the window (it should be a multiple of the page size), while the ACPI MADT parsing code hardcodes the size of the window to 8 KB. This makes sense, considering that ACPI does not bother to describe the size in the first place, under the assumption that platforms implementing ACPI will follow the architecture and not put anything else in the same 64 KB window. So let's just drop the sanity check altogether, and assume that the window is at least 64 KB in size. Fixes: 909777324588 ("KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_init") Signed-off-by: Ard Biesheuvel Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: Do not use kern_hyp_va() with kvm_vgic_global_state

2018-07-22T12:27:41+00:00

Commit 44a497abd621a71c645f06d3d545ae2f46448830 upstream. kvm_vgic_global_state is part of the read-only section, and is usually accessed using a PC-relative address generation (adrp + add). It is thus useless to use kern_hyp_va() on it, and actively problematic if kern_hyp_va() becomes non-idempotent. On the other hand, there is no way that the compiler is going to guarantee that such access is always PC relative. So let's bite the bullet and provide our own accessor. Acked-by: Catalin Marinas Reviewed-by: James Morse Signed-off-by: Marc Zyngier Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock

2018-05-22T14:57:56+00:00

commit bf308242ab98b5d1648c3663e753556bef9bec01 upstream. kvm_read_guest() will eventually look up in kvm_memslots(), which requires either to hold the kvm->slots_lock or to be inside a kvm->srcu critical section. In contrast to x86 and s390 we don't take the SRCU lock on every guest exit, so we have to do it individually for each kvm_read_guest() call. Provide a wrapper which does that and use that everywhere. Note that ending the SRCU critical section before returning from the kvm_read_guest() wrapper is safe, because the data has been *copied*, so we don't need to rely on valid references to the memslot anymore. Cc: Stable # 4.8+ Reported-by: Jan Glauber Signed-off-by: Andre Przywara Acked-by: Christoffer Dall Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: vgic-its: Preserve the revious read from the pending table

2017-12-16T15:25:47+00:00

commit 64afe6e9eb4841f35317da4393de21a047a883b3 upstream. 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 Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: VGIC: Fix command handling while ITS being disabled

2017-12-14T08:28:19+00:00

[ Upstream commit a5e1e6ca94a8cec51571fd62e3eaec269717969c ] The ITS spec says that ITS commands are only processed when the ITS is enabled (section 8.19.4, Enabled, bit[0]). Our emulation was not taking this into account. Fix this by checking the enabled state before handling CWRITER writes. On the other hand that means that CWRITER could advance while the ITS is disabled, and enabling it would need those commands to be processed. Fix this case as well by refactoring actual command processing and calling this from both the GITS_CWRITER and GITS_CTLR handlers. Reviewed-by: Eric Auger Reviewed-by: Christoffer Dall Signed-off-by: Andre Przywara Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: vgic-its: Check result of allocation before use

2017-12-14T08:28:14+00:00

commit 686f294f2f1ae40705283dd413ca1e4c14f20f93 upstream. We miss a test against NULL after allocation. Fixes: 6d03a68f8054 ("KVM: arm64: vgic-its: Turn device_id validation into generic ID validation") Reported-by: AKASHI Takahiro Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: vgic-irqfd: Fix MSI entry allocation

2017-12-14T08:28:14+00:00

commit 150009e2c70cc3c6e97f00e7595055765d32fb85 upstream. 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") Reported-by: AKASHI Takahiro Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: Fix broken GICH_ELRSR big endian conversion

2017-12-14T08:28:14+00:00

commit fc396e066318c0a02208c1d3f0b62950a7714999 upstream. 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. Acked-by: Christoffer Dall Signed-off-by: Christoffer Dall Signed-off-by: Greg Kroah-Hartman

KVM: arm/arm64: Fix occasional warning from the timer work function

2017-12-09T21:01:52+00:00

[ Upstream commit 63e41226afc3f7a044b70325566fa86ac3142538 ] When a VCPU blocks (WFI) and has programmed the vtimer, we program a soft timer to expire in the future to wake up the vcpu thread when appropriate. Because such as wake up involves a vcpu kick, and the timer expire function can get called from interrupt context, and the kick may sleep, we have to schedule the kick in the work function. The work function currently has a warning that gets raised if it turns out that the timer shouldn't fire when it's run, which was added because the idea was that in that case the work should never have been cancelled. However, it turns out that this whole thing is racy and we can get spurious warnings. The problem is that we clear the armed flag in the work function, which may run in parallel with the kvm_timer_unschedule->timer_disarm() call. This results in a possible situation where the timer_disarm() call does not call cancel_work_sync(), which effectively synchronizes the completion of the work function with running the VCPU. As a result, the VCPU thread proceeds before the work function completees, causing changes to the timer state such that kvm_timer_should_fire(vcpu) returns false in the work function. All we do in the work function is to kick the VCPU, and an occasional rare extra kick never harmed anyone. Since the race above is extremely rare, we don't bother checking if the race happens but simply remove the check and the clearing of the armed flag from the work function. Reported-by: Matthias Brugger Reviewed-by: Marc Zyngier Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman