From: Tom Zanussi <zanussi@kernel.org>
To: linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org
Cc: rostedt@goodmis.org, tglx@linutronix.de, C.Emde@osadl.org,
jkacur@redhat.com, bigeasy@linutronix.de,
daniel.wagner@siemens.com, julia@ni.com
Subject: [PATCH RT 8/9] drm/i915: disable tracing on -RT
Date: Fri, 21 Dec 2018 09:21:20 -0600 [thread overview]
Message-ID: <bc045daf7dcb077b845955b25a8f2d1b6eaceac0.1545347029.git.tom.zanussi@linux.intel.com> (raw)
In-Reply-To: <cover.1545347029.git.tom.zanussi@linux.intel.com>
In-Reply-To: <cover.1545347029.git.tom.zanussi@linux.intel.com>
v3.18.129-rt111 rt-stable review patch. If anyone has any objections,
please let me know.
------------------
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[Upstream commit 05cebb309b156646e61b898e92acc8e46c47ba75]
Luca Abeni reported this:
| BUG: scheduling while atomic: kworker/u8:2/15203/0x00000003
| CPU: 1 PID: 15203 Comm: kworker/u8:2 Not tainted 4.19.1-rt3 #10
| Call Trace:
| rt_spin_lock+0x3f/0x50
| gen6_read32+0x45/0x1d0 [i915]
| g4x_get_vblank_counter+0x36/0x40 [i915]
| trace_event_raw_event_i915_pipe_update_start+0x7d/0xf0 [i915]
The tracing events use trace_i915_pipe_update_start() among other events
use functions acquire spin locks. A few trace points use
intel_get_crtc_scanline(), others use ->get_vblank_counter() wich also
might acquire a sleeping lock.
Based on this I don't see any other way than disable trace points on RT.
Cc: stable-rt@vger.kernel.org
Reported-by: Luca Abeni <lucabe72@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
---
drivers/gpu/drm/i915/i915_trace.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_trace.h b/drivers/gpu/drm/i915/i915_trace.h
index f5aa0067755a..3b37567b76c8 100644
--- a/drivers/gpu/drm/i915/i915_trace.h
+++ b/drivers/gpu/drm/i915/i915_trace.h
@@ -1,6 +1,10 @@
#if !defined(_I915_TRACE_H_) || defined(TRACE_HEADER_MULTI_READ)
#define _I915_TRACE_H_
+#ifdef CONFIG_PREEMPT_RT_BASE
+#define NOTRACE
+#endif
+
#include <linux/stringify.h>
#include <linux/types.h>
#include <linux/tracepoint.h>
--
2.14.1
next prev parent reply other threads:[~2018-12-21 15:21 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-21 15:21 [PATCH RT 0/9] Linux 3.18.129-rt111-rc1 Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 1/9] efi: Allow efi=runtime Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 2/9] efi: Disable runtime services on RT Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 3/9] crypto: cryptd - add a lock instead preempt_disable/local_bh_disable Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 4/9] sched/core: Avoid __schedule() being called twice in a row Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 5/9] work-simple: drop a shit statement in SWORK_EVENT_PENDING Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 6/9] tty: serial: pl011: explicitly initialize the flags variable Tom Zanussi
2018-12-21 15:21 ` [PATCH RT 7/9] pinctrl: bcm2835: Use raw spinlock for RT compatibility Tom Zanussi
2018-12-21 15:21 ` Tom Zanussi [this message]
2018-12-21 15:21 ` [PATCH RT 9/9] Linux 3.18.129-rt111-rc1 Tom Zanussi
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=bc045daf7dcb077b845955b25a8f2d1b6eaceac0.1545347029.git.tom.zanussi@linux.intel.com \
--to=zanussi@kernel.org \
--cc=C.Emde@osadl.org \
--cc=bigeasy@linutronix.de \
--cc=daniel.wagner@siemens.com \
--cc=jkacur@redhat.com \
--cc=julia@ni.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rt-users@vger.kernel.org \
--cc=rostedt@goodmis.org \
--cc=tglx@linutronix.de \
/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
all inboxes | Powered by JetHome®