Subject: Re: linux-next: build failure after merge of the mm tree

From: Jason Gunthorpe <[email-masked]>
Date: Tue, 7 Feb 2023 08:17:46 -0400

On Tue, Feb 07, 2023 at 03:37:06PM +1100, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the mm tree, today's linux-next build (powerpc
> ppc64_defconfig) failed like this:
> 
> lib/iov_iter.c: In function 'iov_iter_extract_user_pages':
> lib/iov_iter.c:2143:34: error: 'FOLL_PIN' undeclared (first use in this function); did you mean 'POLL_IN'?
>  2143 |         unsigned int gup_flags = FOLL_PIN;
>       |                                  ^~~~~~~~
>       |                                  POLL_IN
> lib/iov_iter.c:2143:34: note: each undeclared identifier is reported only once for each function it appears in
> 
> Caused by commit
> 
>   0ff325d28700 ("mm/gup: move private gup FOLL_ flags to internal.h")
> 
> interacting with commit
> 
>   895d773054a2 ("iov_iter: Add a function to extract a page list from an iterator")
> 
> from the block tree.
> 
> I have reverted commit 0ff325d28700 for today.  A better resolution
> would be appreciated.

Just s/= FOLL_PIN/= 0/, it is unconditionally set internally when calling
pin_user_pages_fast()

David can you send a patch to the block tree to fix it?

Jason