From: Cyril Hrubis <chrubis@suse.cz>
To: ltp@lists.linux.it
Subject: [LTP] [PATCH] lsmod01: parse a copy of /proc/modules
Date: Mon, 29 Aug 2016 17:17:52 +0200 [thread overview]
Message-ID: <20160829151752.GA1816@rei.lan> (raw)
In-Reply-To: <57C440C0.5050307@oracle.com>
Hi!
Looking into the kernel/module.c the /proc/modules is implemented with
seq_* operations and the list of modules is iterated one by one util
there is a space in buffer. And it looks like the module_mutex is
acquired and released each time we call read(), so there is a chance
that we race against something that loads/unloads kernel modules between
the reads we do. Which would explain why we hit this only under certain
conditions...
But I still do not see how writing to NFS triggers module load/unload or
module refcount increment/decrement. I guess that this would be very
hard to figure out without somebody who is familiar with the nfs code.
--
Cyril Hrubis
chrubis@suse.cz
next prev parent reply other threads:[~2016-08-29 15:17 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-08-29 11:08 [LTP] [PATCH] lsmod01: parse a copy of /proc/modules Stanislav Kholmanskikh
2016-08-29 12:50 ` Cyril Hrubis
2016-08-29 13:05 ` Stanislav Kholmanskikh
2016-08-29 13:34 ` Jan Stancek
2016-08-29 14:00 ` Stanislav Kholmanskikh
2016-08-29 14:03 ` Stanislav Kholmanskikh
2016-08-29 15:17 ` Cyril Hrubis [this message]
2016-08-29 15:49 ` Jan Stancek
2016-10-11 12:03 ` Stanislav Kholmanskikh
2016-10-11 13:38 ` Cyril Hrubis
2016-10-11 15:47 ` Stanislav Kholmanskikh
2016-10-11 16:15 ` Cyril Hrubis
2016-11-09 14:34 ` [LTP] [PATCH] lsmod01: keep the output in variables Stanislav Kholmanskikh
2016-11-09 16:49 ` Cyril Hrubis
2016-11-10 10:07 ` Stanislav Kholmanskikh
2016-11-10 11:39 ` Cyril Hrubis
2016-11-10 14:15 ` Stanislav Kholmanskikh
2016-08-31 13:55 ` [LTP] [PATCH] lsmod01: parse a copy of /proc/modules Cyril Hrubis
2016-09-02 14:12 ` Stanislav Kholmanskikh
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