Re: [PATCH 1/3] mm: print out information of file affected bymemory error

From: Jan Kara
Date: Thu Oct 25 2012 - 15:32:46 EST


On Thu 25-10-12 11:12:47, Naoya Horiguchi wrote:
> Printing out the information about which file can be affected by a
> memory error in generic_error_remove_page() is helpful for user to
> estimate the impact of the error.
>
> Signed-off-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
> ---
> mm/truncate.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git v3.7-rc2.orig/mm/truncate.c v3.7-rc2/mm/truncate.c
> index d51ce92..df0c6ab7 100644
> --- v3.7-rc2.orig/mm/truncate.c
> +++ v3.7-rc2/mm/truncate.c
> @@ -151,14 +151,20 @@ int truncate_inode_page(struct address_space *mapping, struct page *page)
> */
> int generic_error_remove_page(struct address_space *mapping, struct page *page)
> {
> + int ret;
> + struct inode *inode = mapping->host;
> +
This will oops if mapping == NULL. Currently the only caller seems to
check beforehand but still, it's better keep the code as robust as it it.

> if (!mapping)
> return -EINVAL;
> /*
> * Only punch for normal data pages for now.
> * Handling other types like directories would need more auditing.
> */
> - if (!S_ISREG(mapping->host->i_mode))
> + if (!S_ISREG(inode->i_mode))
> return -EIO;
> + pr_info("MCE %#lx: file info pgoff:%lu, inode:%lu, dev:%s\n",
> + page_to_pfn(page), page_index(page),
> + inode->i_ino, inode->i_sb->s_id);
> return truncate_inode_page(mapping, page);
> }
> EXPORT_SYMBOL(generic_error_remove_page);
Otherwise the patch looks OK.

Honza
--
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/