Re: [PATCH] [8/18] BKL-removal: Remove BKL from remote_llseek

[Andi Kleen]

On Monday 28 January 2008 14:38:57 Alan Cox wrote:
> > Also worse really fixing it would be a major change to the VFS 
> > because of the way ->read/write are defined :/
> 
> I don't see a problem there. ->read and ->write update the passed pointer
> which is not the real f_pos anyway. Just the copies need fixing. 

They are effectually doing a decoupled read/modify/write cycle. e.g.:

A               B

read fpos       

                read fpos

fpos += A       fpos += B
                write fpos


write fpos

So you get overlapping reads. Probably not good.

-Andi
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