summaryrefslogtreecommitdiff
path: root/drivers/base/cacheinfo.c
AgeCommit message (Collapse)Author
2015-09-17cpu/cacheinfo: Fix teardown pathBorislav Petkov
Philip Müller reported a hang when booting 32-bit 4.1 kernel on an AMD box. A fragment of the splat was enough to pinpoint the issue: task: f58e0000 ti: f58e8000 task.ti: f58e800 EIP: 0060:[<c135a903>] EFLAGS: 00010206 CPU: 0 EIP is at free_cache_attributes+0x83/0xd0 EAX: 00000001 EBX: f589d46c ECX: 00000090 EDX: 360c2000 ESI: 00000000 EDI: c1724a80 EBP: f58e9ec0 ESP: f58e9ea0 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 CR0: 8005003b CR2: 000000ac CR3: 01731000 CR4: 000006d0 cache_shared_cpu_map_setup() did check sibling CPUs cacheinfo descriptor while the respective teardown path cache_shared_cpu_map_remove() didn't. Fix that. >From tglx's version: to be on the safe side, move the cacheinfo descriptor check to free_cache_attributes(), thus cleaning up the hotplug path a little and making this even more robust. Reported-and-tested-by: Philip Müller <philm@manjaro.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Cc: <stable@vger.kernel.org> # 4.1 Cc: Andre Przywara <andre.przywara@arm.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-kernel@vger.kernel.org Cc: manjaro-dev@manjaro.org Cc: Philip Müller <philm@manjaro.org> Link: https://lkml.kernel.org/r/55B47BB8.6080202@manjaro.org Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-08Merge 4.1-rc7 into driver-core-nextGreg Kroah-Hartman
We want the fixes in this branch as well for testing and merge resolution. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-01drivers/base: cacheinfo: handle absence of cachesSudeep Holla
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>
2015-05-24drivers/base: cacheinfo: fix annoying typo when DT nodes are absentWill Deacon
s/hierarcy/hierarchy/ Maybe the typo will annoy people enough so that they add the missing nodes to their device-tree files, but I still think this is better off fixed. Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-25drivers/base: cacheinfo: validate device node for all the cachesSudeep Holla
On architectures that depend on DT for obtaining cache hierarcy, we need to validate the device node for all the cache indices, failing to do so might result in wrong information being exposed to the userspace. This is quite possible on initial/incomplete versions of the device trees. In such cases, it's better to bail out if all the required device nodes are not present. This patch adds checks for the validation of device node for all the caches and doesn't initialise the cacheinfo if there's any error. Reported-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Cc: stable <stable@vger.kernel.org> # 4.0 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-24drivers/base: cacheinfo: remove noisy error boot messageSudeep Holla
On systems that don't support cacheinfo, this error message can be considered noisy and irrelevant. The error messages can be added to the functions that architectures implement overiding the weak default definition if really required. This patch removes the concerned error message in the generic code. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Reported-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-07drivers: base: support cpu cache information interface to userspace via sysfsSudeep Holla
This patch adds initial support for providing processor cache information to userspace through sysfs interface. This is based on already existing implementations(x86, ia64, s390 and powerpc) and hence the interface is intended to be fully compatible. The main purpose of this generic support is to avoid further code duplication to support new architectures and also to unify all the existing different implementations. This implementation maintains the hierarchy of cache objects which reflects the system's cache topology. Cache devices are instantiated as needed as CPUs come online. The cache information is replicated per-cpu even if they are shared. A per-cpu array of cache information maintained is used mainly for sysfs-related book keeping. It also implements the shared_cpu_map attribute, which is essential for enabling both kernel and user-space to discover the system's overall cache topology. This patch also add the missing ABI documentation for the cacheinfo sysfs interface already, which is well defined and widely used. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> Tested-by: Stephen Boyd <sboyd@codeaurora.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: linux-api@vger.kernel.org Cc: linux390@de.ibm.com Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: x86@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>