linux-kernel - Re: [PATCH v2 2/2] mm/hwpoison: fix fail isolate hugetlbfs page w/ refcount held

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Mon, 10 Aug 2015 01:05:42 +0000
From:	Naoya Horiguchi <n-horiguchi@...jp.nec.com>
To:	Wanpeng Li <wanpeng.li@...mail.com>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	Tony Luck <tony.luck@...el.com>,
	Andi Kleen <andi@...stfloor.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"stable@...r.kernel.org" <stable@...r.kernel.org>
Subject: Re: [PATCH v2 2/2] mm/hwpoison: fix fail isolate hugetlbfs page w/
 refcount held

On Fri, Aug 07, 2015 at 06:16:42PM +0800, Wanpeng Li wrote:
> Hugetlbfs pages will get a refcount in get_any_page() or madvise_hwpoison() 
> if soft offline through madvise. The refcount which held by soft offline 
> path should be released if fail to isolate hugetlbfs pages. This patch fix 
> it by reducing a refcount for both isolate successfully and failure.
> 
> Cc: <stable@...r.kernel.org> # 3.9+
> Signed-off-by: Wanpeng Li <wanpeng.li@...mail.com> 

Acked-by: Naoya Horiguchi <n-horiguchi@...jp.nec.com>

> ---
>  mm/memory-failure.c |   13 ++++++-------
>  1 files changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/mm/memory-failure.c b/mm/memory-failure.c
> index 001f1ba..8077b1c 100644
> --- a/mm/memory-failure.c
> +++ b/mm/memory-failure.c
> @@ -1557,13 +1557,12 @@ static int soft_offline_huge_page(struct page *page, int flags)
>  	unlock_page(hpage);
>  
>  	ret = isolate_huge_page(hpage, &pagelist);
> -	if (ret) {
> -		/*
> -		 * get_any_page() and isolate_huge_page() takes a refcount each,
> -		 * so need to drop one here.
> -		 */
> -		put_page(hpage);
> -	} else {
> +	/*
> +	 * get_any_page() and isolate_huge_page() takes a refcount each,
> +	 * so need to drop one here.
> +	 */
> +	put_page(hpage);
> +	if (!ret) {
>  		pr_info("soft offline: %#lx hugepage failed to isolate\n", pfn);
>  		return -EBUSY;
>  	}
> -- 
> 1.7.1
> --
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/