From: Josh Triplett <josh@joshtriplett.org>
To: Theodore Ts'o <tytso@thunk.org>
Cc: linux-fsdevel@vger.kernel.org, linux-sparse@vger.kernel.org
Subject: Re: What does this sparse warning mean in posix_acl.h?
Date: Sat, 17 Aug 2013 09:17:18 -0700 [thread overview]
Message-ID: <20130817161718.GA18897@leaf> (raw)
In-Reply-To: <nsxtxio1jeh.fsf@lambda.thunk.org>
On Sat, Aug 17, 2013 at 10:28:22AM -0400, Theodore Ts'o wrote:
> It apparently has something to do with rcu and "address spaces" but I'm
> not completely sure what sparse is complaining about --- and whether it
> is a false positive or a bug in the posix_acl.h.
>
> Can someone explain what's going on, and whether it's something to be
> concerned about?
[...]
> /usr/projects/linux/ext4/include/linux/posix_acl.h:137:9: warning: incorrect type in assignment (different address spaces)
> /usr/projects/linux/ext4/include/linux/posix_acl.h:137:9: expected struct posix_acl *<noident>
> /usr/projects/linux/ext4/include/linux/posix_acl.h:137:9: got struct posix_acl [noderef] <asn:4>*<noident>
> /usr/projects/linux/ext4/include/linux/posix_acl.h:137:9: warning: incorrect type in assignment (different address spaces)
> /usr/projects/linux/ext4/include/linux/posix_acl.h:137:9: expected struct posix_acl *<noident>
> /usr/projects/linux/ext4/include/linux/posix_acl.h:137:9: got struct posix_acl [noderef] <asn:4>*<noident>
Address space 4 is __rcu. This warning means you accessed an RCU
pointer directly, without using the appropriate RCU primitive
(rcu_assign_pointer, rcu_dereference, etc).
- Josh Triplett
next prev parent reply other threads:[~2013-08-17 16:17 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-08-17 14:28 What does this sparse warning mean in posix_acl.h? Theodore Ts'o
2013-08-17 16:16 ` Linus Torvalds
2013-08-17 20:55 ` Theodore Ts'o
2013-08-17 21:14 ` Linus Torvalds
2013-08-17 21:23 ` Theodore Ts'o
2013-08-17 21:31 ` Linus Torvalds
2013-08-17 21:23 ` Linus Torvalds
2013-08-17 16:17 ` Josh Triplett [this message]
2013-08-17 16:33 ` Linus Torvalds
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