Re: [PATCH 3/3] btrfs check: Attempt to fix misordered keys with bitflips in them

[Hugo Mills <hugo@carfax.org.uk>]

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On Fri, May 16, 2014 at 04:22:36PM +0200, David Sterba wrote:
> On Mon, May 05, 2014 at 06:07:51PM +0100, Hugo Mills wrote:
> > If precisely one of those bitflips puts the broken key back into order
> > relative to its two neighbours, we probably have a fix for the bitflip,
> > and so we write it back to the FS.
> 
> This sounds safe enough to me.  I'll add the patch to integration but
> before I push it further upstream I'd really like to see the bitflip fix
> in action, so if you already have testing images, please let me know.

   Here's the one I mostly used to test with -- it's a 32 GiB sparse
full filesystem image, with a file full of zeroes in it. It has a
single bitflip in the csum tree created by hand with a hex editor, and
then the csum fixed up afterwards, again by hand.

   Hugo.

[1] http://carfax.org.uk/files/temp/testfs.img.tar.gz

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=== Hugo Mills: hugo@... carfax.org.uk | darksatanic.net | lug.org.uk ===
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