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* [BUG] packet loss with PROVE_LOCKING, bisected to EDAC fix
@ 2016-03-21 21:42 Chris Bainbridge
  2016-03-22  5:31 ` Borislav Petkov
  0 siblings, 1 reply; 5+ messages in thread
From: Chris Bainbridge @ 2016-03-21 21:42 UTC (permalink / raw)
  To: bp; +Cc: linux-edac, linux-kernel, mchehab, markus, tony.luck

Hi,

I was testing something on an old server (Dell T105 opteron) and noticed
packet loss after updating the kernel from 3.10 to 4.5. The test was:

On Dell run: iperf -s
On another system: iperf3 -c dell -u -b 20M -l 1k -t 1000

This sends a 20mbit UDP stream to the Dell. It works fine normally (0%
packet loss), but when CONFIG_PROVE_LOCKING is enabled there is high
(35%) packet loss. (DEBUG_LOCKDEP also seems to cause packet loss)

The packet loss bisected back to:

commit 88d84ac97378c2f1d5fec9af1e8b7d9a662d6b00
Author: Borislav Petkov <bp@suse.de>
Date:   Fri Jul 19 12:28:25 2013 +0200

    EDAC: Fix lockdep splat

I have confirmed that the commit preceding this (v3.11-rc1) is fine and
that 88d84a introduced the bug.

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2016-03-22 11:12 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-03-21 21:42 [BUG] packet loss with PROVE_LOCKING, bisected to EDAC fix Chris Bainbridge
2016-03-22  5:31 ` Borislav Petkov
2016-03-22  8:18   ` Peter Zijlstra
2016-03-22  9:16   ` Chris Bainbridge
2016-03-22 11:12     ` Borislav Petkov

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