From: Stephen Hemminger <shemminger@vyatta.com>
To: David Miller <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Subject: ethtool physical identify vs netlink locking?
Date: Tue, 29 Mar 2011 13:52:52 -0700 [thread overview]
Message-ID: <20110329135252.116bf5e0@s6510> (raw)
Right now if an administrator uses the ethtool function to identify network
interface, the netlink lock can be held indefinitely. In other words, doing
"ethtool -p eth1" will stop all other netlink activity. This is bad, imagine
the case of an operator doing that to find a NIC in a rack, and because of
the netlink lockout all routing daemon activity stops.
There are several possible solutions but most involve fixing all the device
drivers (24). Options:
1. Have device driver drop and reacquire rtnl() while blinking
2. Have ethtool core drop rtnl before calling device driver
3. Add per-device ethtool rtnl lock
#1 is the least disruption
#2 means additional locking maybe required for each device driver
#3 seems like excessive overhead.
Comments?
next reply other threads:[~2011-03-29 20:52 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-29 20:52 Stephen Hemminger [this message]
2011-03-30 0:07 ` ethtool physical identify vs netlink locking? Ben Hutchings
2011-03-30 0:13 ` David Miller
2011-03-30 0:23 ` Stephen Hemminger
2011-03-30 1:35 ` Michał Mirosław
2011-03-30 6:29 ` Stephen Hemminger
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=20110329135252.116bf5e0@s6510 \
--to=shemminger@vyatta.com \
--cc=davem@davemloft.net \
--cc=netdev@vger.kernel.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.