Re: [PATCH] IBM Power RAID driver (ipr) 2.0.6

[Matthew Wilcox <willy@debian.org>]

On Mon, May 10, 2004 at 03:38:57PM -0500, James Bottomley wrote:
> On Tue, 2004-05-04 at 12:52, Brian King wrote:
> > Here is the latest version of the LLD for the IBM Power RAID family of
> > adapters. This includes several IBM iSeries and pSeries SCSI adapters.
> > Please apply.
> 
> The problem is your use of list_head pointers in packed structures.  You
> can't simply pass a pointer to a misaligned structure to a common kernel
> function and expect it to work: the packed attribute is lost doing this
> and what you end up with is a misaligned pointer reference.

It also causes gcc to pessimise references to this structure; often
doing byte-loads instead of larger quantities.  Why does this struct
need to be packed?

-- 
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