From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: Deadlock in /proc/xen/xenbus watch+read on 3.17+
 (maybe earlier)
Date: Thu, 19 Mar 2015 11:10:38 +0000
Message-ID: <550AAEAE.1090609@citrix.com>
References: <20150319011911.GA29029@mail-itl>
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To: =?windows-1252?Q?Marek_Marczykowski-G=F3recki?= <marmarek@invisiblethingslab.com>, xen-devel <xen-devel@lists.xen.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>, David Vrabel <david.vrabel@citrix.com>
List-Id: xen-devel@lists.xenproject.org

On 19/03/15 01:19, Marek Marczykowski-G=F3recki wrote:
> Hi,
> =

> I've hit some deadlock in kernel xenstore client exposed via
> /proc/xen/xenbus. Steps to reproduce are simple:
> int main() {
> 	struct xs_handle *xs;
> 	xs =3D xs_open(0);
> 	xs_watch(xs, "domid", "token");
> 	xs_read(xs, 0, "name", NULL);
> 	return 0;
> }

This test program works for me on 4.0-rc4 in a dom0 and domU.  I also
don't see any xenbus changes in the kernel that could cause a regression
like this.

Perhaps you not running a vanilla kernel?

David