diff mbox series

[v2,01/14] memory-failure: fetch compound_head after pgmap_pfn_valid()

Message ID 20210617184507.3662-2-joao.m.martins@oracle.com (mailing list archive)
State New
Headers show
Series mm, sparse-vmemmap: Introduce compound pagemaps | expand

Commit Message

Joao Martins June 17, 2021, 6:44 p.m. UTC
memory_failure_dev_pagemap() at the moment assumes base pages (e.g.
dax_lock_page()).  For pagemap with compound pages fetch the
compound_head in case a tail page memory failure is being handled.

Currently this is a nop, but in the advent of compound pages in
dev_pagemap it allows memory_failure_dev_pagemap() to keep working.

Reported-by: Jane Chu <jane.chu@oracle.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
---
 mm/memory-failure.c | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

HORIGUCHI NAOYA(堀口 直也) June 20, 2021, 11:56 p.m. UTC | #1
On Thu, Jun 17, 2021 at 07:44:54PM +0100, Joao Martins wrote:
> memory_failure_dev_pagemap() at the moment assumes base pages (e.g.
> dax_lock_page()).  For pagemap with compound pages fetch the
> compound_head in case a tail page memory failure is being handled.
> 
> Currently this is a nop, but in the advent of compound pages in
> dev_pagemap it allows memory_failure_dev_pagemap() to keep working.
> 
> Reported-by: Jane Chu <jane.chu@oracle.com>
> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>

Looks good to me.

Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>

> ---
>  mm/memory-failure.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index e684b3d5c6a6..f1be578e488f 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -1519,6 +1519,12 @@ static int memory_failure_dev_pagemap(unsigned long pfn, int flags,
>  		goto out;
>  	}
>  
> +	/*
> +	 * Pages instantiated by device-dax (not filesystem-dax)
> +	 * may be compound pages.
> +	 */
> +	page = compound_head(page);
> +
>  	/*
>  	 * Prevent the inode from being freed while we are interrogating
>  	 * the address_space, typically this would be handled by
> -- 
> 2.17.1
>
Joao Martins June 21, 2021, 1:50 p.m. UTC | #2
On 6/21/21 12:56 AM, HORIGUCHI NAOYA(堀口 直也) wrote:
> On Thu, Jun 17, 2021 at 07:44:54PM +0100, Joao Martins wrote:
>> memory_failure_dev_pagemap() at the moment assumes base pages (e.g.
>> dax_lock_page()).  For pagemap with compound pages fetch the
>> compound_head in case a tail page memory failure is being handled.
>>
>> Currently this is a nop, but in the advent of compound pages in
>> dev_pagemap it allows memory_failure_dev_pagemap() to keep working.
>>
>> Reported-by: Jane Chu <jane.chu@oracle.com>
>> Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
> 
> Looks good to me.
> 
> Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
> 
Thanks!
diff mbox series

Patch

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index e684b3d5c6a6..f1be578e488f 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1519,6 +1519,12 @@  static int memory_failure_dev_pagemap(unsigned long pfn, int flags,
 		goto out;
 	}
 
+	/*
+	 * Pages instantiated by device-dax (not filesystem-dax)
+	 * may be compound pages.
+	 */
+	page = compound_head(page);
+
 	/*
 	 * Prevent the inode from being freed while we are interrogating
 	 * the address_space, typically this would be handled by