linux-kernel - Re: [PATCH v4 2/8] staging: zcache: zero-filled pages awareness

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

Message-ID: <51498FCE.60603@oracle.com>
Date:	Wed, 20 Mar 2013 18:30:38 +0800
From:	Bob Liu <bob.liu@...cle.com>
To:	Wanpeng Li <liwanp@...ux.vnet.ibm.com>
CC:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Dan Magenheimer <dan.magenheimer@...cle.com>,
	Seth Jennings <sjenning@...ux.vnet.ibm.com>,
	Konrad Rzeszutek Wilk <konrad@...nok.org>,
	Minchan Kim <minchan@...nel.org>, linux-mm@...ck.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 2/8] staging: zcache: zero-filled pages awareness


> @@ -641,16 +691,22 @@ static void zcache_pampd_free(void *pampd, struct tmem_pool *pool,
>  {
>  	struct page *page = NULL;
>  	unsigned int zsize, zpages;
> +	bool zero_filled = false;
>  
>  	BUG_ON(preemptible());
> -	if (pampd_is_remote(pampd)) {
> +
> +	if (pampd == (void *)ZERO_FILLED)
> +		zero_filled = true;
> +
> +	if (pampd_is_remote(pampd) && !zero_filled) {
>  		BUG_ON(!ramster_enabled);
>  		pampd = ramster_pampd_free(pampd, pool, oid, index, acct);
>  		if (pampd == NULL)
>  			return;
>  	}
>  	if (is_ephemeral(pool)) {
> -		page = zbud_free_and_delist((struct zbudref *)pampd,
> +		if (!zero_filled)
> +			page = zbud_free_and_delist((struct zbudref *)pampd,
>  						true, &zsize, &zpages);

This check should also apply for !is_ephemeral(pool).

>  		if (page)
>  			dec_zcache_eph_pageframes();
> @@ -667,7 +723,7 @@ static void zcache_pampd_free(void *pampd, struct tmem_pool *pool,
>  	}
>  	if (!is_local_client(pool->client))
>  		ramster_count_foreign_pages(is_ephemeral(pool), -1);
> -	if (page)
> +	if (page && !zero_filled)
>  		zcache_free_page(page);
>  }
>  
> 

-- 
Regards,
-Bob
--
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/