From: Greg KH <gregkh@linuxfoundation.org>
To: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 20/28] coresight: tmc-etr: Do not call smp_processor_id() from preemptible
Date: Thu, 20 Jun 2019 08:02:50 +0200 [thread overview]
Message-ID: <20190620060250.GA26319@kroah.com> (raw)
In-Reply-To: <20190619195318.19254-21-mathieu.poirier@linaro.org>
On Wed, Jun 19, 2019 at 01:53:10PM -0600, Mathieu Poirier wrote:
> From: Suzuki K Poulose <suzuki.poulose@arm.com>
>
> During a perf session we try to allocate buffers on the "node" associated
> with the CPU the event is bound to. If it's 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/1743
> caller is alloc_etr_buf.isra.6+0x80/0xa0
> CPU: 1 PID: 1743 Comm: perf Not tainted 5.1.0-rc6-147786-g116841e #344
> Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno Development Platform, BIOS EDK II Feb 1 2019
> Call trace:
> dump_backtrace+0x0/0x150
> show_stack+0x14/0x20
> dump_stack+0x9c/0xc4
> debug_smp_processor_id+0x10c/0x110
> alloc_etr_buf.isra.6+0x80/0xa0
> tmc_alloc_etr_buffer+0x12c/0x1f0
> etm_setup_aux+0x1c4/0x230
> rb_alloc_aux+0x1b8/0x2b8
> perf_mmap+0x35c/0x478
> mmap_region+0x34c/0x4f0
> do_mmap+0x2d8/0x418
> vm_mmap_pgoff+0xd0/0xf8
> ksys_mmap_pgoff+0x88/0xf8
> __arm64_sys_mmap+0x28/0x38
> el0_svc_handler+0xd8/0x138
> el0_svc+0x8/0xc
>
> Use NUMA_NO_NODE hint instead of using the current node for events
> not bound to CPUs.
>
> Fixes: 855ab61c16bf70b646 ("coresight: tmc-etr: Refactor function tmc_etr_setup_perf_buf()")
> Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
> ---
> drivers/hwtracing/coresight/coresight-tmc-etr.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
Why isn't this being submitted for 5.2-final? Why wait until 5.3 to fix
this?
thanks,
greg k-h
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2019-06-20 6:03 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-19 19:52 [PATCH 00/28] coresight: next v5.2-rc5 (V2) Mathieu Poirier
2019-06-19 19:52 ` [PATCH 01/28] coresight: Rename of_coresight to coresight-platform Mathieu Poirier
2019-06-19 19:52 ` [PATCH 02/28] coresight: platform: Make memory allocation helper generic Mathieu Poirier
2019-06-19 19:52 ` [PATCH 03/28] coresight: Make sure device uses DT for obsolete compatible check Mathieu Poirier
2019-06-19 19:52 ` [PATCH 04/28] coresight: Introduce generic platform data helper Mathieu Poirier
2019-06-19 19:52 ` [PATCH 05/28] coresight: Make device to CPU mapping generic Mathieu Poirier
2019-06-19 19:52 ` [PATCH 06/28] coresight: Remove cpu field from platform data Mathieu Poirier
2019-06-19 19:52 ` [PATCH 07/28] coresight: Remove name from platform description Mathieu Poirier
2019-06-19 19:52 ` [PATCH 08/28] coresight: Cleanup coresight_remove_conns Mathieu Poirier
2019-06-19 19:52 ` [PATCH 09/28] coresight: Reuse platform data structure for connection tracking Mathieu Poirier
2019-06-19 19:53 ` [PATCH 10/28] coresight: Rearrange platform data probing Mathieu Poirier
2019-06-19 19:53 ` [PATCH 11/28] coresight: Add support for releasing platform specific data Mathieu Poirier
2019-06-19 19:53 ` [PATCH 12/28] coresight: platform: Use fwnode handle for device search Mathieu Poirier
2019-06-19 19:53 ` [PATCH 13/28] coresight: Use fwnode handle instead of device names Mathieu Poirier
2019-06-19 19:53 ` [PATCH 14/28] coresight: Use platform agnostic names Mathieu Poirier
2019-06-19 19:53 ` [PATCH 15/28] coresight: stm: ACPI support for parsing stimulus base Mathieu Poirier
2019-06-19 19:53 ` [PATCH 16/28] coresight: Support for ACPI bindings Mathieu Poirier
2019-06-19 19:53 ` [PATCH 17/28] coresight: acpi: Support for AMBA components Mathieu Poirier
2019-06-19 19:53 ` [PATCH 18/28] coresight: acpi: Support for platform devices Mathieu Poirier
2019-06-19 19:53 ` [PATCH 19/28] coresight: Add dummy definition for of_coresight_get_cpu() Mathieu Poirier
2019-06-19 19:53 ` [PATCH 20/28] coresight: tmc-etr: Do not call smp_processor_id() from preemptible Mathieu Poirier
2019-06-20 6:02 ` Greg KH [this message]
2019-06-19 19:53 ` [PATCH 21/28] coresight: tmc-etr: alloc_perf_buf: Do not call smp_processor_id " Mathieu Poirier
2019-06-20 6:03 ` Greg KH
2019-06-19 19:53 ` [PATCH 22/28] coresight: tmc-etf: " Mathieu Poirier
2019-06-20 6:03 ` Greg KH
2019-06-19 19:53 ` [PATCH 23/28] coresight: etb10: " Mathieu Poirier
2019-06-20 6:04 ` Greg KH
2019-06-19 19:53 ` [PATCH 24/28] coresight: Potential uninitialized variable in probe() Mathieu Poirier
2019-06-20 6:04 ` Greg KH
2019-06-19 19:53 ` [PATCH 25/28] coresight: etm3x: Smatch: Fix potential NULL pointer dereference Mathieu Poirier
2019-06-20 6:04 ` Greg KH
2019-06-20 21:38 ` Mathieu Poirier
2019-06-21 6:59 ` Greg KH
2019-06-19 19:53 ` [PATCH 26/28] coresight: tmc: " Mathieu Poirier
2019-06-20 6:05 ` Greg KH
2019-06-20 21:42 ` Mathieu Poirier
2019-06-21 6:59 ` Greg KH
2019-06-19 19:53 ` [PATCH 27/28] coresight: platform: add OF/APCI dependency Mathieu Poirier
2019-06-19 19:53 ` [PATCH 28/28] coresight: replicator: Add terminate entry for acpi_device_id tables Mathieu Poirier
2019-06-20 6:08 ` [PATCH 00/28] coresight: next v5.2-rc5 (V2) Greg KH
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190620060250.GA26319@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=mathieu.poirier@linaro.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).