From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To: Roosen Henri <Henri.Roosen@ginzinger.com>
Cc: "linux-rt-users@vger.kernel.org" <linux-rt-users@vger.kernel.org>
Subject: Re: Kernel v4.14.52-rt34 triggered a kernel-oops
Date: Tue, 23 Oct 2018 10:56:45 +0900 [thread overview]
Message-ID: <20181023015645.GA748@jagdpanzerIV> (raw)
In-Reply-To: <1540215012.26412.7.camel@ginzinger.com>
On (10/22/18 13:30), Roosen Henri wrote:
> Hi RT-experts,
>
> One of our ARM iMX6Q systems running an SMP PREEMPT RT kernel version
> based on v4.14.52-rt34 triggered a kernel-oops after about 60 days
> duration test (running cyclic-test and additional load apps).
>
> Looking at the trace (see https://paste.debian.net/1048486/), PC is
> incorrect. LR is c016816c, so the processor just executed the
> instruction at c0168168:
>
> c0168168: e12fff33 blx r3
> (kernel/printk/printk.c:1666)
>
> With r3 being ee4fe01c, the processor has jumped to that location
> causing the OOPS.
>
> Looking at the console_unlock disassembly (see
> https://paste.debian.net/1048485/), r3 should have the con->write()
> function pointer. The console pointer con is retrieved while walking
> the console_drivers list.
>
> So, I guess the list gets corrupted, maybe some kind of concurrency
> issue? Unfortunately there are a lot of locking primitives used in the
> console_unlock() function and some RT-specific code, so it's not so
> easy to find the root-cause at first glance. Could someone of you have
> a look?
Did you register/unregister consoles during the test? Nothing else
should modify the console drivers list.
-ss
prev parent reply other threads:[~2018-10-23 10:17 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-22 13:30 Kernel v4.14.52-rt34 triggered a kernel-oops Roosen Henri
2018-10-23 1:56 ` Sergey Senozhatsky [this message]
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=20181023015645.GA748@jagdpanzerIV \
--to=sergey.senozhatsky.work@gmail.com \
--cc=Henri.Roosen@ginzinger.com \
--cc=linux-rt-users@vger.kernel.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).