linux-kernel - Re: [patch 1/2] x86: track memtype for RAM in page struct

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: <200809131924.46859.elendil@planet.nl>
Date:	Sat, 13 Sep 2008 19:24:45 +0200
From:	Frans Pop <elendil@...net.nl>
To:	Venkatesh Pallipadi <venkatesh.pallipadi@...el.com>
Cc:	arjan@...ux.intel.com, mingo@...e.hu, tglx@...utronix.de,
	hpa@...or.com, andi@...stfloor.org, linux-kernel@...r.kernel.org,
	suresh.b.siddha@...el.com, venkatesh.pallipadi@...el.com
Subject: Re: [patch 1/2] x86: track memtype for RAM in page struct

Corrections for a few typos and some suggestions for minor improvements
in the comment.

Cheers,
FJP

Venkatesh Pallipadi wrote:
> --- tip.orig/arch/x86/mm/pat.c  2008-09-12 16:03:33.000000000 -0700
> +++ tip/arch/x86/mm/pat.c       2008-09-12 16:23:33.000000000 -0700
> @@ -211,6 +211,75 @@ static struct memtype *cached_entry;
> static u64 cached_start;
> 
> /*
> + * RED-PEN:  TODO: Add PageReserved() check aswell here,

"as well"

> + * once we add SetPageReserved() to all the drivers using
> + * set_memory_* or set_pages_*
> + *
> + * This will help prevent accidentally freeing pages
> + * before setting the attribute back to WB.
> + */
> +
> +/*
> + * For RAM pages, mark the pages with non WB attribute using

s/non WB/without the WB/ ?

> + * PG_arch_1. We allow only one set_memory_uc() or set_memory_wc()
> + * on a RAM page at a time before marking it as WB again. This is ok,
> + * because only one(driver) will be owning the page and doing

"one (driver)"
Maybe move "set_memory_*()" to next line (looks better).

> + * set_memory_*() calls.
> + *
> + * For now, we use PG_arch_1 to track that the RAM page is being mapped
> + * as non WB. In future, based on the need we can use one or more flags

s/based on the need/if needed,/

> + * (or some other mechanism in page_struct) to keep track of the actual
> + * attribute that the page is mapped to.
> + */
--
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/