This is a note to let you know that I've just added the patch titled

    spi: trigger trace event for message-done before mesg->complete

to the 3.19-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     spi-trigger-trace-event-for-message-done-before-mesg-complete.patch
and it can be found in the queue-3.19 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 391949b6f02121371e3d7d9082c6d17fd9853034 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <[email protected]>
Date: Wed, 18 Mar 2015 11:27:28 +0100
Subject: spi: trigger trace event for message-done before mesg->complete
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From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <[email protected]>

commit 391949b6f02121371e3d7d9082c6d17fd9853034 upstream.

With spidev the mesg->complete callback points to spidev_complete.
Calling this unblocks spidev_sync and so spidev_sync_write finishes. As
the struct spi_message just read is a local variable in
spidev_sync_write and recording the trace event accesses this message
the recording is better done first. The same can happen for
spidev_sync_read.

This fixes an oops observed on a 3.14-rt system with spidev activity
after

        echo 1 > /sys/kernel/debug/tracing/events/spi/enable

 .

Signed-off-by: Uwe Kleine-König <[email protected]>
Signed-off-by: Mark Brown <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/spi/spi.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1073,13 +1073,14 @@ void spi_finalize_current_message(struct
                                "failed to unprepare message: %d\n", ret);
                }
        }
+
+       trace_spi_message_done(mesg);
+
        master->cur_msg_prepared = false;
 
        mesg->state = NULL;
        if (mesg->complete)
                mesg->complete(mesg->context);
-
-       trace_spi_message_done(mesg);
 }
 EXPORT_SYMBOL_GPL(spi_finalize_current_message);
 


Patches currently in stable-queue which might be from 
[email protected] are

queue-3.19/clocksource-efm32-fix-a-null-pointer-dereference.patch
queue-3.19/spi-trigger-trace-event-for-message-done-before-mesg-complete.patch
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