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] [thread-next>] [day] [month] [year] [list]
Date:	Sun, 07 Sep 2014 21:41:30 -0700
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Mahesh Bandewar <maheshb@...gle.com>
Cc:	Nikolay Aleksandrov <nikolay@...hat.com>,
	Jay Vosburgh <j.vosburgh@...il.com>,
	Veaceslav Falico <vfalico@...hat.com>,
	Andy Gospodarek <andy@...yhouse.net>,
	David Miller <davem@...emloft.net>,
	netdev <netdev@...r.kernel.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Maciej Zenczykowski <maze@...gle.com>
Subject: Re: [PATCH net-next v1 2/2] bonding: Simplify the xmit function for
 modes that use xmit_hash

On Sun, 2014-09-07 at 19:23 -0700, Mahesh Bandewar wrote:
> >
> I'm not expecting any writer protection here since all the paths are
> covered with some or the other lock at this moment. Just though that
> performing array manipulation in RCU context would be useful.


It is not useful. It is confusing only.

If you think of RCU as a replacement for reader/writer lock, its obvious
that once you get the writer lock, there is no need to get the reader
lock.

Extract from Documentation/RCU/whatisRCU.txt :

Use rcu_read_lock() and rcu_read_unlock() to guard RCU
read-side critical sections.

Use some solid scheme (such as locks or semaphores) to
keep concurrent updates from interfering with each other.



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists