WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] debugging pv domU kernel lockups, kdb & hvc0 or gdbsx ?

To: xen-devel@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-devel] debugging pv domU kernel lockups, kdb & hvc0 or gdbsx ?
From: Bruce Edge <bruce.edge@xxxxxxxxx>
Date: Sun, 13 Jun 2010 09:03:02 -0700
Delivery-date: Sun, 13 Jun 2010 09:06:56 -0700
Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:date:message-id :subject:from:to:content-type; bh=ZOPfah7xCsOnHzrQd+O7eKDDO9jdX8+Jpi1psL7wF7c=; b=HhZ94OvElPJ8Fm2n7PbBF/CqWV/UsHqlbltGVEWLGvUoUN2+EPY/w1SIsuoixsC6W+ +w7dI+iLM/KiNvuHwdvmSkfcsWPaGEyxYGNGH5upucryLIPh+MVEypFYpHxrWvrKHo0a 1A5dh/IlAiF86M0sxnn7SRypXv6NgOIEUcwZI=
Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=aWArPP03/dLUR7YX81qua13l1rBTZPKUGq2UB4ycGXsqDRSPvuSHbogBQ8bF09gCn/ m2RGCZtCJY3YUbPrMP+/EVhqRYnzX1k/Hkz+8YUZpKOn1ZEPxfro1FJTkTtG7Z3wY6On VSq6zvJ8+8nkuXPrn8lHq7MhI9c2jGR+d99kY=
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
With hvm domains we've always used kdb over serial, the standard
http://oss.sgi.com/projects/kdb version was all we needed. Just like
the good old bare metal days.

Does this not work with pv domains?

The pv-ops 2.6.32.x branch kernel with the most recent 2.6.32 kdb
patches appears not to work. Or, at least kdb doesn't recognize the
domU's hvc0 console.

The <ESC>KDB hotkey combination doesn't work, and when I drop into kdb:

Entering kdb (current=0xffff88009722ad80, pid 6958) on processor 0 Oops: <NULL>
due to oops @ 0xffffffff812d6c70
     r15 = 0x00000000000000f8      r14 = 0x0000000000000000
     r13 = 0x00000000000000f0      r12 = 0x0000000000000087
      bp = 0xffff8800a41f9e28       bx = 0xffff8800a41f9e5c
     r11 = 0x0000000000000000      r10 = 0xffffea000210e200
      r9 = 0xffff8800a42f4000       r8 = 0x00000000000207b0
      ax = 0x0000000000000200       cx = 0x0000000000000001
      dx = 0x0000000000000007       si = 0x00000000000000f8
      di = 0x0000000000000000  orig_ax = 0xffffffffffffffff
      ip = 0xffffffff812d6c70       cs = 0x000000010000e030
   flags = 0x0000000000010012       sp = 0xffff8800a41f9de8
      ss = 0x000000000000e02b &regs = 0xffff8800a41f9d38

...there is no kdb prompt and the console is unresponsive.

Is this a problem with kdb expecting a serial console and the  the
hvc0 console on the pv domU?

The hvm domU shows:
# tty
/dev/ttyS0

whereas the pv domU shows:
# tty
/dev/hvc0

Do I just need to get kdb to use hvc0? If so, how?

Or, do we need to switch to gdbsx for pv domU debugging?
ala http://xenbits.xensource.com/ext/debuggers.hg ?
Or, is this the definitive domU debugging text
http://www.kernel.org/doc/ols/2006/ols2006v2-pages-9-24.pdf ?

Thanks.

-Bruce

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>
  • [Xen-devel] debugging pv domU kernel lockups, kdb & hvc0 or gdbsx ?, Bruce Edge <=