Marc Zyngier b20c9f29c5 arm/arm64: KVM: detect CPU reset on CPU_PM_EXIT ... Commit 1fcf7ce0c6 (arm: kvm: implement CPU PM notifier) added support for CPU power-management, using a cpu_notifier to re-init KVM on a CPU that entered CPU idle. The code assumed that a CPU entering idle would actually be powered off, loosing its state entierely, and would then need to be reinitialized. It turns out that this is not always the case, and some HW performs CPU PM without actually killing the core. In this case, we try to reinitialize KVM while it is still live. It ends up badly, as reported by Andre Przywara (using a Calxeda Midway): [ 3.663897] Kernel panic - not syncing: unexpected prefetch abort in Hyp mode at: 0x685760 [ 3.663897] unexpected data abort in Hyp mode at: 0xc067d150 [ 3.663897] unexpected HVC/SVC trap in Hyp mode at: 0xc0901dd0 The trick here is to detect if we've been through a full re-init or not by looking at HVBAR (VBAR_EL2 on arm64). This involves implementing the backend for __hyp_get_vectors in the main KVM HYP code (rather small), and checking the return value against the default one when the CPU notifier is called on CPU_PM_EXIT. Reported-by: Andre Przywara <osp@andrep.de> Tested-by: Andre Przywara <osp@andrep.de> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Rob Herring <rob.herring@linaro.org> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>		2014-02-27 19:27:10 +01:00
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boot	arm64: dts: Reduce size of virtio block device for foundation model	2013-12-20 16:20:21 +00:00
configs	arm64: defconfig: Expand default enabled features	2014-02-07 17:17:28 +00:00
include	A small error handling problem and a compile breakage for ARM64.	2014-02-14 11:10:49 -08:00
kernel	arm64: atomics: fix use of acquire + release for full barrier semantics	2014-02-07 16:45:43 +00:00
kvm	arm/arm64: KVM: detect CPU reset on CPU_PM_EXIT	2014-02-27 19:27:10 +01:00
lib	arm64: atomics: fix use of acquire + release for full barrier semantics	2014-02-07 16:45:43 +00:00
mm	arm64: simplify pgd_alloc	2014-02-05 10:45:07 +00:00
xen	xen/arm,arm64: enable SWIOTLB_XEN	2013-10-10 13:40:44 +00:00
Kconfig	arm64: defconfig: Expand default enabled features	2014-02-07 17:17:28 +00:00
Kconfig.debug	arm64: Remove duplicate DEBUG_STACK_USAGE config	2013-10-02 18:03:26 +01:00
Makefile	arm64: big-endian: add big-endian support to top-level arch Makefile	2013-10-25 15:59:31 +01:00