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Date: Thu, 26 Jan 2012 18:54:49 +0100
From: Orjan Friberg <of@flatfrog.com>
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To: Paul Walmsley <paul@pwsan.com>
Subject: Re: CONFIG_PREEMPT and JFFS2 oops
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On 01/26/2012 05:57 PM, Paul Walmsley wrote:
>>
>> You just throw away best_buf here, don't you?
>
> You're right.  It's even worse than that.  best_buf will contain the data
> from the last compressor used.  And it will be prematurely freed.  Here's
> a fixed version.

I've tested this version for a while now with the same result as before.

No oopses, no spinlock violations.  I copied a 2MB file from the SD/MMC 
partition to the two JFFS2 partitions and md5summ'ed it a bunch of 
times.  After that I unmounted and remounted both partitions.

I do see a steady memory usage increase when doing continuous testing, 
but whether that's normal I don't know.  I see at least some of it being 
reclaimed when unmounting the JFFS2 partitions (grep jffs2 /proc/slabinfo).

-- 
Orjan Friberg
FlatFrog Laboratories AB