]> git.proxmox.com Git - mirror_ubuntu-bionic-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)
committerKhalid Elmously <khalid.elmously@canonical.com>
Fri, 6 Mar 2020 07:13:20 +0000 (02:13 -0500)
commit764be15e64ddd736c202f3673ee7c3de79fead26
treee4119aba464905368caf98241da1b11d6f60695f
parentffeb15398675a974c1bbf365bac006af49fff17d
coresight: etb10: Do not call smp_processor_id from preemptible

BugLink: https://bugs.launchpad.net/bugs/1864261
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>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
drivers/hwtracing/coresight/coresight-etb10.c