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3370e13aa4
On some simulators like GEM5, caches may not be simulated. In those cases, the cache levels and leaves will be zero and will result in following exception: Unable to handle kernel NULL pointer dereference at virtual address 0040 pgd = ffffffc0008fa000 [00000040] *pgd=00000009f6807003, *pud=00000009f6807003, *pmd=00000009f6808003, *pte=006000002c010707 Internal error: Oops: 96000005 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 1 Comm: swapper/0 Not tainted 4.1.0-rc5 #198 task: ffffffc9768a0000 ti: ffffffc9768a8000 task.ti: ffffffc9768a8000 PC is at detect_cache_attributes+0x98/0x2c8 LR is at detect_cache_attributes+0x88/0x2c8 kcalloc(0) returns a special value ZERO_SIZE_PTR which is non-NULL value but results in fault only on any attempt to dereferencing it. So checking for the non-NULL pointer will not suffice. This patch checks for non-zero cache leaf nodes and returns error if there are no cache leaves in detect_cache_attributes. Cc: <stable@vger.kernel.org> # 3.19.x Cc: Will Deacon <will.deacon@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reported-by: William Wang <william.wang@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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.. | ||
power | ||
regmap | ||
attribute_container.c | ||
base.h | ||
bus.c | ||
cacheinfo.c | ||
class.c | ||
component.c | ||
container.c | ||
core.c | ||
cpu.c | ||
dd.c | ||
devcoredump.c | ||
devres.c | ||
devtmpfs.c | ||
dma-coherent.c | ||
dma-contiguous.c | ||
dma-mapping.c | ||
driver.c | ||
firmware_class.c | ||
firmware.c | ||
hypervisor.c | ||
init.c | ||
isa.c | ||
Kconfig | ||
Makefile | ||
map.c | ||
memory.c | ||
module.c | ||
node.c | ||
pinctrl.c | ||
platform.c | ||
property.c | ||
soc.c | ||
syscore.c | ||
topology.c | ||
transport_class.c |