Re: [PATCH v2] block: Fix dio_bio_alloc() to set BIO_PAGE_PINNED

[Jens Axboe]

On 6/12/23 2:24 PM, David Howells wrote:
>     
> Fix dio_bio_alloc() to set BIO_PAGE_PINNED, not BIO_PAGE_REFFED, so that
> the bio code unpins the pinned pages rather than putting a ref on them.
> 
> The issue was causing:
> 
>         WARNING: CPU: 6 PID: 2220 at mm/gup.c:76 try_get_folio
> 
> This can be caused by creating a file on a loopback UDF filesystem, opening
> it O_DIRECT and making two writes to it from the same source buffer.

What is this against?

-- 
Jens Axboe