mirror of https://github.com/torvalds/linux.git
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> |
||
|---|---|---|
| .. | ||
| power | ||
| regmap | ||
| Kconfig | ||
| Makefile | ||
| 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.c | ||
| firmware_class.c | ||
| hypervisor.c | ||
| init.c | ||
| isa.c | ||
| map.c | ||
| memory.c | ||
| module.c | ||
| node.c | ||
| pinctrl.c | ||
| platform.c | ||
| property.c | ||
| soc.c | ||
| syscore.c | ||
| topology.c | ||
| transport_class.c | ||