linux-kernel - Re: [PATCH v9 0/10] iommu/vt-d: Fix intel vt-d faults in kdump kernel

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: <20150507132536.GA4559@localhost.localdomain>
Date:	Thu, 7 May 2015 21:25:36 +0800
From:	Dave Young <dyoung@...hat.com>
To:	Joerg Roedel <joro@...tes.org>
Cc:	"Li, Zhen-Hua" <zhen-hual@...com>, dwmw2@...radead.org,
	indou.takao@...fujitsu.com, bhe@...hat.com, vgoyal@...hat.com,
	iommu@...ts.linux-foundation.org, linux-kernel@...r.kernel.org,
	linux-pci@...r.kernel.org, kexec@...ts.infradead.org,
	alex.williamson@...hat.com, ddutile@...hat.com,
	ishii.hironobu@...fujitsu.com, bhelgaas@...gle.com,
	doug.hatch@...com, jerry.hoemann@...com, tom.vaden@...com,
	li.zhang6@...com, lisa.mitchell@...com, billsumnerlinux@...il.com,
	rwright@...com
Subject: Re: [PATCH v9 0/10] iommu/vt-d: Fix intel vt-d faults in kdump kernel

On 05/06/15 at 10:16am, Joerg Roedel wrote:
> On Wed, May 06, 2015 at 09:46:49AM +0800, Dave Young wrote:
> > For the original problem, the key issue is dmar faults cause kdump kernel
> > hang so that vmcore can not be saved. I do not know the reason why it hangs
> > I think it is acceptable if kdump kernel boot ok with some dma errors..
> 
> It hangs because some devices can't handle the DMAR faults and the kdump
> kernel can't initialize them and will hang itself. For that it doesn't
> matter whether the fault was caused by a read or write request.

Ok, thanks for explanation. so it explains sometimes kdump kernel boot ok
with faults, sometimes it hangs instead.

Dave
--
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/