RE: [PATCH v3 2/3] xen/privcmd: Mark pages as dirty

[Paul Durrant]

> -----Original Message-----
> From: Souptick Joarder <jrdr.linux@xxxxxxxxx>
> Sent: 12 July 2020 04:40
> To: boris.ostrovsky@xxxxxxxxxx; jgross@xxxxxxxx; sstabellini@xxxxxxxxxx
> Cc: xen-devel@xxxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Souptick Joarder
> <jrdr.linux@xxxxxxxxx>; John Hubbard <jhubbard@xxxxxxxxxx>; Paul Durrant <xadimgnik@xxxxxxxxx>
> Subject: [PATCH v3 2/3] xen/privcmd: Mark pages as dirty
> 
> pages need to be marked as dirty before unpinned it in
> unlock_pages() which was oversight. This is fixed now.
> 
> Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx>
> Suggested-by: John Hubbard <jhubbard@xxxxxxxxxx>
> Reviewed-by: Juergen Gross <jgross@xxxxxxxx>
> Cc: John Hubbard <jhubbard@xxxxxxxxxx>
> Cc: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
> Cc: Paul Durrant <xadimgnik@xxxxxxxxx>

Reviewed-by: Paul Durrant <paul@xxxxxxx>

> ---
>  drivers/xen/privcmd.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
> index b001673..079d35b 100644
> --- a/drivers/xen/privcmd.c
> +++ b/drivers/xen/privcmd.c
> @@ -611,8 +611,11 @@ static void unlock_pages(struct page *pages[], unsigned int nr_pages)
>  {
>  	unsigned int i;
> 
> -	for (i = 0; i < nr_pages; i++)
> +	for (i = 0; i < nr_pages; i++) {
> +		if (!PageDirty(pages[i]))
> +			set_page_dirty_lock(pages[i]);
>  		put_page(pages[i]);
> +	}
>  }
> 
>  static long privcmd_ioctl_dm_op(struct file *file, void __user *udata)
> --
> 1.9.1