linux-kernel - Re: [PATCH] 9p/xen: fix init sequence

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: <a15245c9-9be6-4de7-84a8-693931b1b3aa@suse.com>
Date: Thu, 21 Nov 2024 13:27:52 +0100
From: Juergen Gross <jgross@...e.com>
To: Dominique Martinet <asmadeus@...ewreck.org>,
 Alexander Merritt <alexander@...ra.dev>
Cc: v9fs@...ts.linux.dev, linux-kernel@...r.kernel.org,
 xen-devel@...ts.xenproject.org, Eric Van Hensbergen <ericvh@...nel.org>,
 Latchesar Ionkov <lucho@...kov.net>,
 Christian Schoenebeck <linux_oss@...debyte.com>,
 Simon Horman <horms@...nel.org>, Alex Zenla <alex@...ra.dev>,
 Ariadne Conill <ariadne@...adne.space>
Subject: Re: [PATCH] 9p/xen: fix init sequence

On 21.11.24 13:23, Dominique Martinet wrote:
> Alexander Merritt wrote on Tue, Nov 19, 2024 at 09:16:33PM +0000:
>> From: Alex Zenla <alex@...ra.dev>
>>
>> Large amount of mount hangs observed during hotplugging of 9pfs devices. The
>> 9pfs Xen driver attempts to initialize itself more than once, causing the
>> frontend and backend to disagree: the backend listens on a channel that the
>> frontend does not send on, resulting in stalled processing.
>>
>> Only allow initialization of 9p frontend once.
> 
> I'm not familiar with the xen bringup so I don't understand how the
> patch guarantees this -- otherend_changed calls are guaranted to be
> seralized for a given frontend?

Yes. They are all executed by a single kernel thread.


Juergen

Download attachment "OpenPGP_0xB0DE9DD628BF132F.asc" of type "application/pgp-keys" (3684 bytes)

Download attachment "OpenPGP_signature.asc" of type "application/pgp-signature" (496 bytes)