linux-kernel - Re: [PATCH] fix kvm kdump regression

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] [day] [month] [year] [list]

Message-ID: <4C91CE6E.5030500@kernel.org>
Date:	Thu, 16 Sep 2010 09:59:42 +0200
From:	Tejun Heo <tj@...nel.org>
To:	caiqian@...hat.com
CC:	linux-kernel <linux-kernel@...r.kernel.org>,
	kexec <kexec@...ts.infradead.org>, graff.yang@...il.com,
	Marcelo Tosatti <mtosatti@...hat.com>, dhowells@...hat.com,
	sonic.adi@...il.com, Avi Kivity <avi@...hat.com>,
	Chris Lalancette <clalance@...hat.com>, stable@...nel.org,
	Cliff Wickman <cpw@....com>
Subject: Re: [PATCH] fix kvm kdump regression

On 09/16/2010 06:57 AM, caiqian@...hat.com wrote:
> 020ec6537aa65c18e9084c568d7b94727f2026fd introduced a regression that an empty vmcore was generated during kdump on a kvm guest.
> ioremap: invalid physical address db74000000000000
> ------------[ cut here ]------------
> WARNING: at arch/x86/mm/ioremap.c:83 __ioremap_caller+0x307/0x380()
> Hardware name: KVM
> Modules linked in:
> Pid: 1, comm: swapper Not tainted 2.6.36-rc2-mm1+ #2
> Call Trace:
>  [<ffffffff8105f48f>] warn_slowpath_common+0x7f/0xc0
>  [<ffffffff8103052e>] ? copy_oldmem_page+0x4e/0xc0
>  [<ffffffff8105f4ea>] warn_slowpath_null+0x1a/0x20
>  [<ffffffff8103f0a7>] __ioremap_caller+0x307/0x380
>  [<ffffffff8103f1f7>] ioremap_nocache+0x17/0x20
>  [<ffffffff8103052e>] copy_oldmem_page+0x4e/0xc0
>  [<ffffffff811af4ca>] read_from_oldmem+0x7a/0xb0
>  [<ffffffff81c4f70b>] merge_note_headers_elf64.clone.1+0x6c/0x21f
>  [<ffffffff8103056e>] ? copy_oldmem_page+0x8e/0xc0
>  [<ffffffff811af4ca>] ? read_from_oldmem+0x7a/0xb0
>  [<ffffffff81c4fa5b>] vmcore_init+0x19d/0x396
>  [<ffffffff81c4f8be>] ? vmcore_init+0x0/0x396
>  [<ffffffff81002053>] do_one_initcall+0x43/0x190
>  [<ffffffff81c278ab>] kernel_init+0x2a0/0x330
>  [<ffffffff8100be84>] kernel_thread_helper+0x4/0x10
>  [<ffffffff81c2760b>] ? kernel_init+0x0/0x330
>  [<ffffffff8100be80>] ? kernel_thread_helper+0x0/0x10
> ---[ end trace 93d72a36b9146f22 ]---
> Kdump: vmcore not initialized
> 
> This patch fixed it by reverting a chunk of the above commit and 9983b6f0cf8263e51bcf4c8a9dc0c1ef175b3c60 which is based on it.
> 
> Signed-off-by: CAI Qian <caiqian@...hat.com>

Sorry about the delay but I'm prepping a debug patch.  Let's root
cause and see if it can be fixed without reverting it as there are
further changes which depend on the commit and we'll have to hunt it
down anyway.

Thanks.

-- 
tejun
--
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/