linux-kernel - Re: [PATCH v7u1 26/31] x86: Don't enable swiotlb if there is not enough ram for it

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:	Fri, 4 Jan 2013 15:26:03 -0700
From:	Shuah Khan <shuahkhan@...il.com>
To:	Yinghai Lu <yinghai@...nel.org>
Cc:	Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...e.hu>,
	"H. Peter Anvin" <hpa@...or.com>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Borislav Petkov <bp@...en8.de>, Jan Kiszka <jan.kiszka@....de>,
	Jason Wessel <jason.wessel@...driver.com>,
	linux-kernel@...r.kernel.org,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
	Joerg Roedel <joro@...tes.org>
Subject: Re: [PATCH v7u1 26/31] x86: Don't enable swiotlb if there is not
 enough ram for it

On Fri, Jan 4, 2013 at 3:10 PM, Yinghai Lu <yinghai@...nel.org> wrote:
> On Fri, Jan 4, 2013 at 1:02 PM, Shuah Khan <shuahkhan@...il.com> wrote:
>> Pani'cing the system doesn't sound like a good option to me in this
>> case. This change to disable swiotlb is made for kdump. However, with
>> this change several system fail to boot, unless crashkernel_low=72M is
>> specified.
>
> this patchset is new feature to put second kdump kernel above 4G.
>
I understand this is just one of the patches to implement the new
kdump feature. However, I think regression on existing behavior with a
panic is a bit of a big hammer. Thie change causes panic on systems
even when kdump is not enabled, if I understand it correctly.

Granted kdump gets enabled by several distros, but it is not a
required feature. However, expecting system to boot with devices that
require swiotlb fully functioning is a basic feature. So I would argue
that not breaking the basic functionality is a higher priority over
enabling kdump in this case.

-- Shuah
--
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/