All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Roger Pau Monné" <roger.pau@citrix.com>
To: xen-devel@lists.xenproject.org, Jan Beulich <JBeulich@suse.com>,
	Mukesh Rathor <mukesh.rathor@oracle.com>,
	Tim Deegan <tim@xen.org>
Subject: Removing the PVH assert in arch/x86/hvm/io.c:87
Date: Thu, 4 Dec 2014 17:35:59 +0100	[thread overview]
Message-ID: <54808D6F.302@citrix.com> (raw)

Hello,

I've just stumbled upon this assert while testing PVH on different
hardware. It was added in 7c4870 as a safe belt, but it turns out INS
and OUTS go through handle_mmio. So using this instructions from a PVH
guest basically kills Xen.

I've removed it and everything seems fine, so I'm considering sending a
patch for 4.5 in order to have it removed. I think the path that could
trigger the crash because of the missing vioapic stuff is already
guarded by the other chunk added in the same patch.

Roger.

             reply	other threads:[~2014-12-04 16:36 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-04 16:35 Roger Pau Monné [this message]
2014-12-05  1:04 ` Removing the PVH assert in arch/x86/hvm/io.c:87 Mukesh Rathor
2014-12-05  9:15 ` Jan Beulich
2014-12-05 11:07   ` Roger Pau Monné
2014-12-05 11:24     ` David Vrabel
2014-12-05 11:26     ` Jan Beulich

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=54808D6F.302@citrix.com \
    --to=roger.pau@citrix.com \
    --cc=JBeulich@suse.com \
    --cc=mukesh.rathor@oracle.com \
    --cc=tim@xen.org \
    --cc=xen-devel@lists.xenproject.org \
    /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.