From: Avi Kivity <avi@redhat.com>
To: Anthony Liguori <anthony@codemonkey.ws>
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: Wed, 08 Jul 2009 21:17:55 +0300 [thread overview]
Message-ID: <4A54E2D3.3080005@redhat.com> (raw)
In-Reply-To: <4A54E146.4070806@codemonkey.ws>
On 07/08/2009 09:11 PM, Anthony Liguori wrote:
> Mark McLoughlin wrote:
>> It only makes sense to have one per getfd command and ...
>
> It would be silly to pass many fds. fds are scarce resources and you
> don't want to get into a position where you're queuing fds.
If you issue N getfd commands, you've queued N fds.
> If a management tool wants to send an fd, it should issue the monitor
> command that needs the fd along with the fd via SCM_RIGHTS, and then
> wait for that command to complete before issuing another command that
> needs an fd.
>
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.
--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.
next prev parent reply other threads:[~2009-07-08 18:17 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 [this message]
2009-07-11 1:15 ` Jamie Lokier
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