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Date: Tue, 24 Jun 2008 10:07:44 +0200
From: Jens Axboe <jens.axboe@oracle.com>
To: Mikulas Patocka <mpatocka@redhat.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] Avoid bio_endio recursion
Message-ID: <20080624080744.GL20851@kernel.dk>
References: <Pine.LNX.4.64.0806240118250.24220@engineering.redhat.com>
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On Tue, Jun 24 2008, Mikulas Patocka wrote:
> Hi
> 
> bio_endio calls bi_end_io callback. In case of stacked devices (raid, dm), 
> bio_end_io may call bio_endio again, up to an unspecified length.
> 
> The crash because of stack overflow was really observed on sparc64. And 
> this recursion was one of the contributing factors (using 9 stack frames 
> --- that is 1728 bytes).

Looks good, I like the concept. Can you please make it a little less
goto driven, though? The next_bio and goto next_bio could just be a
while().

-- 
Jens Axboe