From: Jamie Lokier <jamie@shareable.org>
To: Avi Kivity <avi@redhat.com>
Cc: Mark McLoughlin <markmc@redhat.com>, qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [PATCH 2/5] Add SCM_RIGHTS support to unix socket character devices
Date: Sat, 11 Jul 2009 02:15:29 +0100 [thread overview]
Message-ID: <20090711011529.GL30322@shareable.org> (raw)
In-Reply-To: <4A54E2D3.3080005@redhat.com>
Avi Kivity wrote:
> Why impose unnecessary restrictions? I agree that the guest shouldn't
> use qemu as an fd store. But putting such limits in the code is laying
> a trap for the client, which will show up in rare cases, for example two
> client threads issuing unrelated getfd commands with the client author
> not knowing it should serialize them.
If there is an fd queue, then it clearly must be limited on the QEMU
side to avoid becoming an fd store.
A client issuing unrelated commands must be aware of that limitation.
The queue length could be 1, or it could be 10 per monitor to allow
some command overlap, but the client will need to be aware of it and
limit overlap.
That means the limit must be documented in any (future :-) monitor
protocol documentation.
-- Jamie
prev parent reply other threads:[~2009-07-11 1:15 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-07-06 17:30 [Qemu-devel] [PATCH 0/3] Allow host_net_add monitor command accept file descriptors Mark McLoughlin
2009-07-06 17:30 ` [Qemu-devel] [PATCH 1/3] Make tcp_chr_read() use recvmsg() Mark McLoughlin
2009-07-06 17:31 ` [Qemu-devel] [PATCH 2/3] Add SCM_RIGHTS support to unix socket character devices Mark McLoughlin
2009-07-06 17:32 ` [Qemu-devel] [PATCH 3/3] Add support for fd=msgfd for tap and socket networking Mark McLoughlin
2009-07-07 5:28 ` [Qemu-devel] [PATCH 0/3] Allow host_net_add monitor command accept file descriptors Avi Kivity
2009-07-07 7:43 ` Mark McLoughlin
2009-07-07 7:52 ` Avi Kivity
2009-07-07 8:13 ` Mark McLoughlin
2009-07-07 9:03 ` Avi Kivity
2009-07-07 10:06 ` Daniel P. Berrange
2009-07-08 14:56 ` Mark McLoughlin
2009-07-08 14:57 ` [Qemu-devel] [PATCH 1/5] Make tcp_chr_read() use recvmsg() Mark McLoughlin
2009-07-08 14:57 ` [Qemu-devel] [PATCH 2/5] Add SCM_RIGHTS support to unix socket character devices Mark McLoughlin
2009-07-08 14:57 ` [Qemu-devel] [PATCH 3/5] Add getfd and closefd monitor commands Mark McLoughlin
2009-07-08 14:57 ` [Qemu-devel] [PATCH 4/5] Add monitor_get_fd() command for fetching named fds Mark McLoughlin
2009-07-08 14:57 ` [Qemu-devel] [PATCH 5/5] Add support for fd=name to tap and socket networking Mark McLoughlin
2009-07-08 15:26 ` [Qemu-devel] [PATCH 3/5] Add getfd and closefd monitor commands Avi Kivity
2009-07-08 16:03 ` Mark McLoughlin
2009-07-08 16:15 ` Avi Kivity
2009-07-08 18:08 ` Anthony Liguori
2009-07-08 18:11 ` Avi Kivity
2009-07-08 18:21 ` Anthony Liguori
2009-07-08 18:32 ` Avi Kivity
2009-07-08 18:50 ` Anthony Liguori
2009-07-08 19:52 ` Avi Kivity
2009-07-11 1:12 ` Jamie Lokier
2009-07-21 16:40 ` Mark McLoughlin
2009-07-21 16:53 ` [Qemu-devel] [PATCH] Make tcp_chr_read() use recvmsg() Mark McLoughlin
2009-07-21 17:13 ` Blue Swirl
2009-07-22 0:00 ` Jamie Lokier
2009-07-22 8:10 ` Mark McLoughlin
2009-07-22 8:11 ` [Qemu-devel] [PATCH 1/5] " Mark McLoughlin
2009-07-22 8:11 ` [Qemu-devel] [PATCH 2/5] Add SCM_RIGHTS support to unix socket character devices Mark McLoughlin
2009-08-13 16:20 ` Cam Macdonell
2009-08-14 6:38 ` Mark McLoughlin
2009-07-22 8:11 ` [Qemu-devel] [PATCH 3/5] Add getfd and closefd monitor commands Mark McLoughlin
2009-07-22 8:11 ` [Qemu-devel] [PATCH 4/5] Add monitor_get_fd() command for fetching named fds Mark McLoughlin
2009-07-22 8:11 ` [Qemu-devel] [PATCH 5/5] Add support for fd=name to tap and socket networking Mark McLoughlin
2009-07-23 13:37 ` Mark McLoughlin
2009-07-21 16:53 ` [Qemu-devel] [PATCH] Add SCM_RIGHTS support to unix socket character devices Mark McLoughlin
2009-07-21 16:53 ` [Qemu-devel] [PATCH] Add getfd and closefd monitor commands Mark McLoughlin
2009-07-21 16:53 ` [Qemu-devel] [PATCH] Add monitor_get_fd() command for fetching named fds Mark McLoughlin
2009-07-21 16:53 ` [Qemu-devel] [PATCH] Add support for fd=name to tap and socket networking Mark McLoughlin
2009-07-22 2:20 ` [Qemu-devel] [PATCH 3/5] Add getfd and closefd monitor commands Anthony Liguori
2009-07-22 8:09 ` Mark McLoughlin
2009-07-23 7:00 ` [Qemu-devel] " Jan Kiszka
2009-07-23 7:51 ` Mark McLoughlin
2009-07-08 15:25 ` [Qemu-devel] [PATCH 2/5] Add SCM_RIGHTS support to unix socket character devices Avi Kivity
2009-07-08 16:04 ` Mark McLoughlin
2009-07-08 16:17 ` Avi Kivity
2009-07-08 18:11 ` Anthony Liguori
2009-07-08 18:17 ` Avi Kivity
2009-07-11 1:15 ` Jamie Lokier [this message]
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