linux-kernel - Re: [PATCH v2 2/2] x86/mm/pat, drivers/media/ivtv: move pat warn and replace WARN() with pr

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]

Date:	Mon, 6 Jul 2015 23:53:20 -0700
From:	"Luis R. Rodriguez" <mcgrof@...not-panic.com>
To:	Andy Lutomirski <luto@...capital.net>,
	Ingo Molnar <mingo@...nel.org>
Cc:	Andy Walls <awalls@...metrocast.net>,
	Andy Walls <andy@...verblocksystems.net>,
	Toshi Kani <toshi.kani@...com>, Hyong-Youb Kim <hkim@...i.com>,
	Benjamin Herrenschmidt <benh@...nel.crashing.org>,
	"Luis R. Rodriguez" <mcgrof@...not-panic.com>,
	Borislav Petkov <bp@...e.de>,
	Mauro Carvalho Chehab <mchehab@....samsung.com>,
	Doug Ledford <dledford@...hat.com>,
	Fengguang Wu <fengguang.wu@...el.com>,
	linux-media@...r.kernel.org, linux-rdma@...r.kernel.org,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 2/2] x86/mm/pat, drivers/media/ivtv: move pat warn and
 replace WARN() with pr_warn()

On Mon, Jul 6, 2015 at 5:44 PM, Luis R. Rodriguez <mcgrof@...e.com> wrote:
> If we really wanted to we could consider arch_phys_wc_add()

I mean adding a __arch_phys_wc_add() which does not check for pat_enabled().

> and
> deal with that this will not check for pat_enabled() and forces MTRR...
> I think Andy Luto won't like that very much though ? I at least don't
> like it since we did all this work to finally leave only 1 piece of
> code with direct MTRR access... Seems a bit sad. Since ipath will
> be removed we'd have only ivtv driver using this API, I am not sure if
> its worth it.

Since ipath is going away soon we'd just have one driver with the icky
#ifdef code. I'd rather see that and then require semantics / grammer
rules to require ioremap_wc() when used with arch_phys_wc_add(). I
don't think ivtv is worth to consider breaking the semantics and
requirements.

> Thoughts?

 Luis
--
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/