All of lore.kernel.org
 help / color / mirror / Atom feed
From: Xiexiangyou <xiexiangyou@huawei.com>
To: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: <kvm@vger.kernel.org>, <guangrong.xiao@linux.intel.com>,
	<pbonzini@redhat.com>
Subject: Re: [RFH] NULL pointer dereference oops occurs when running kvm VM
Date: Tue, 16 Aug 2016 16:25:43 +0800	[thread overview]
Message-ID: <787289f9-ef25-5b25-6b01-e557db57cb44@huawei.com> (raw)
In-Reply-To: <20160815125011.GA16471@potion>

Thanks for your reply :)

I'm confused that it throw an exception "NULL pointer dereference" when
implement "mov    0x45114(%rip),%rax" instruction. Because "0x45114(%rip)" couldn't be NULL.
Will thread stack overflow result in Oops which is hard to explain like this?

Reproducing is ongoing...


Regards~

On 2016/8/15 20:50, Radim Krčmář wrote:
> 2016-08-12 17:08+0800, Xiexiangyou:
>> Kvm vm runs in hardware server with intel broadwell CPU. A oops exception occurs.
>>
>> kernel version: 3.0.93
>> kvm version: 3.6
>> CPU: And the CPU is Intel(R) Xeon(R) CPU E5-2618L v4 @ 2.20GHz.
>>
>> The message as follows :
>> <1>[25808.222049] BUG: unable to handle kernel NULL pointer dereference at           (null)
>> <1>[25808.230539] IP: [<ffffffffa021f3c5>] vcpu_enter_guest+0x555/0x790 [kvm]
>> <4>[25808.237496] PGD 0
>> <1>[25808.239839] Thread overran stack, or stack corrupted
> 
> This could be an imporant lead.  Stack overrun usually happened with xfs
> or similar operations, but your kernel does not look standard ...
> Can you reproduce after increasing the stack size with 6538b8ea886e
> ("x86_64: expand kernel stack to 16K")?
> 
> .
> 


  parent reply	other threads:[~2016-08-16  8:26 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-08-12  9:08 [RFH] NULL pointer dereference oops occurs when running kvm VM Xiexiangyou
     [not found] ` <57AD9821.6010804@windriver.com>
2016-08-14  8:45   ` Xiexiangyou
     [not found] ` <20160815125011.GA16471@potion>
2016-08-16  8:25   ` Xiexiangyou [this message]
2016-08-16 16:49     ` Radim Krčmář

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=787289f9-ef25-5b25-6b01-e557db57cb44@huawei.com \
    --to=xiexiangyou@huawei.com \
    --cc=guangrong.xiao@linux.intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=rkrcmar@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.