]> git.ipfire.org Git - people/arne_f/kernel.git/commit
coresight: etb10: Do not call smp_processor_id from preemptible
authorSuzuki K Poulose <suzuki.poulose@arm.com>
Thu, 20 Jun 2019 22:12:36 +0000 (16:12 -0600)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 29 Jan 2020 14:02:39 +0000 (15:02 +0100)
commita4681849419e18f0592961f7aa88bef19eaa66f3
treefc5534be4ae81acd5583261bbefe021a832afb67
parent3e0151deb2872230e2a05c11d56f3a80cd5698f7
coresight: etb10: Do not call smp_processor_id from preemptible

commit 730766bae3280a25d40ea76a53dc6342e84e6513 upstream.

During a perf session we try to allocate buffers on the "node" associated
with the CPU the event is bound to. If it is not bound to a CPU, we
use the current CPU node, using smp_processor_id(). However this is unsafe
in a pre-emptible context and could generate the splats as below :

 BUG: using smp_processor_id() in preemptible [00000000] code: perf/2544

Use NUMA_NO_NODE hint instead of using the current node for events
not bound to CPUs.

Fixes: 2997aa4063d97fdb39 ("coresight: etb10: implementing AUX API")
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: stable <stable@vger.kernel.org> # 4.6+
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20190620221237.3536-5-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/hwtracing/coresight/coresight-etb10.c