Subject: Re: linux-next: manual merge of the btrfs tree with the fscache tree

From: Ira Weiny <[email-masked]>
Date: Thu, 11 Feb 2021 17:07:41 -0800

On Fri, Feb 12, 2021 at 10:38:10AM +1100, Stephen Rothwell wrote:
> Hi all,
> 
> Today's linux-next merge of the btrfs tree got a conflict in:
> 
>   lib/iov_iter.c
> 
> between commit:
> 
>   11432a3cc061 ("iov_iter: Add ITER_XARRAY")
> 
> from the fscache tree and commit:
> 
>   325a835476e3 ("iov_iter: Remove memzero_page() in favor of zero_user()")

I don't seem to have that commit after fetching linux-next?  Should I have it?

This is where I fetched from.

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

After doing that I don't see the zero_user() as below.

All that said the resolution below seems correct.

Ira

> 
> from the btrfs tree.
> 
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
> 
> -- 
> Cheers,
> Stephen Rothwell
> 
> diff --cc lib/iov_iter.c
> index 24413884b5ca,aa0d03b33a1e..000000000000
> --- a/lib/iov_iter.c
> +++ b/lib/iov_iter.c
> @@@ -1048,9 -961,8 +1028,9 @@@ size_t iov_iter_zero(size_t bytes, stru
>   		return pipe_zero(bytes, i);
>   	iterate_and_advance(i, bytes, v,
>   		clear_user(v.iov_base, v.iov_len),
> - 		memzero_page(v.bv_page, v.bv_offset, v.bv_len),
> + 		zero_user(v.bv_page, v.bv_offset, v.bv_len),
>  -		memset(v.iov_base, 0, v.iov_len)
>  +		memset(v.iov_base, 0, v.iov_len),
> - 		memzero_page(v.bv_page, v.bv_offset, v.bv_len)
> ++		zero_user(v.bv_page, v.bv_offset, v.bv_len)
>   	)
>   
>   	return bytes;