Re: [PATCH 002 of 4] md: Make 'repair' actually work for raid1.

From: Neil Brown
Date: Wed Jan 24 2007 - 02:28:15 EST


On Tuesday January 23, akpm@xxxxxxxx wrote:
> On Tue, 23 Jan 2007 11:26:52 +1100
> NeilBrown <neilb@xxxxxxx> wrote:
>
> > + for (j = 0; j < vcnt ; j++)
> > + memcpy(page_address(sbio->bi_io_vec[j].bv_page),
> > + page_address(pbio->bi_io_vec[j].bv_page),
> > + PAGE_SIZE);
>
> I trust these BIOs are known to only contain suitably-allocated, MD-private
> pages? Because if these pages can be user pages then this change is
> spectacularly buggy ;)

Your trust is well placed.
This is in the 'resync' path, were all buffers are allocated in lowmem
and are full pages and so-forth, so this is perfectly safe.

NeilBrown
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