Re: [PATCH 0/2] fuse: fix regression in fuse_get_user_pages()

On 09/10/2014 01:51 PM, Miklos Szeredi wrote:

On Wed, Sep 03, 2014 at 02:10:23PM +0400, Maxim Patlasov wrote:

quoted

Hi,

The patchset fixes a regression introduced by the following commits:

c7f3888ad7f0 ("switch iov_iter_get_pages() to passing maximal number of pages")
c9c37e2e6378 ("fuse: switch to iov_iter_get_pages()")

Hmm, instead of reverting to passing maxbytes *instead* of maxpages, I think the
right fix is to *add* the maxbytes argument.

Just maxbytes alone doesn't have enough information in it.  E.g. 4096 contiguous
bytes could occupy 1 or 2 pages, depending on the starting offset.

Yes, you are right. I missed that c7f3888ad7f0 fixed a subtle bug in 
get_pages_iovec().

So how about the following (untested) patch?

Your patch works fine in my tests.

Thanks,
Maxim

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