Andre Przywara b3aff6ccbb KVM: arm/arm64: Fix reference to uninitialised VGIC ... Commit 4b4b4512da ("arm/arm64: KVM: Rework the arch timer to use level-triggered semantics") brought the virtual architected timer closer to the VGIC. There is one occasion were we don't properly check for the VGIC actually having been initialized before, but instead go on to check the active state of some IRQ number. If userland hasn't instantiated a virtual GIC, we end up with a kernel NULL pointer dereference: ========= Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ffffffc9745c5000 [00000000] *pgd=00000009f631e003, *pud=00000009f631e003, *pmd=0000000000000000 Internal error: Oops: 96000006 [#2] PREEMPT SMP Modules linked in: CPU: 0 PID: 2144 Comm: kvm_simplest-ar Tainted: G D 4.5.0-rc2+ #1300 Hardware name: ARM Juno development board (r1) (DT) task: ffffffc976da8000 ti: ffffffc976e28000 task.ti: ffffffc976e28000 PC is at vgic_bitmap_get_irq_val+0x78/0x90 LR is at kvm_vgic_map_is_active+0xac/0xc8 pc : [<ffffffc0000b7e28>] lr : [<ffffffc0000b972c>] pstate: 20000145 .... ========= Fix this by bailing out early of kvm_timer_flush_hwstate() if we don't have a VGIC at all. Reported-by: Cosmin Gorgovan <cosmin@linux-geek.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Cc: <stable@vger.kernel.org> # 4.4.x		2016-02-08 15:23:39 +00:00
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arch_timer.c	KVM: arm/arm64: Fix reference to uninitialised VGIC	2016-02-08 15:23:39 +00:00
trace.h	arm/arm64: KVM: Add tracepoints for vgic and timer	2015-10-22 23:01:48 +02:00
vgic-v2-emul.c	KVM: arm/arm64: rework MMIO abort handling to use KVM MMIO bus	2015-03-30 17:07:19 +01:00
vgic-v2.c	KVM: arm/arm64: Merge vgic_set_lr() and vgic_sync_lr_elrsr()	2015-11-04 15:29:49 +01:00
vgic-v3-emul.c	KVM: arm: vgic: Drop useless Group0 warning	2015-06-17 09:58:12 +01:00
vgic-v3.c	arm64: KVM: Turn system register numbers to an enum	2015-12-14 11:30:43 +00:00
vgic.c	* s390: Support for runtime instrumentation within guests,	2016-01-12 13:22:12 -08:00
vgic.h	KVM: arm/arm64: rework MMIO abort handling to use KVM MMIO bus	2015-03-30 17:07:19 +01:00