Date: Sat, 10 Sep 2005 12:00:01 -0700 (PDT)
From: Linus Torvalds <torvalds@osdl.org>
To: "Paolo 'Blaisorblade' Giarrusso" <blaisorblade@yahoo.it>
cc: Jeff Dike <jdike@addtoit.com>, LKML <linux-kernel@vger.kernel.org>,
       user-mode-linux-devel@lists.sourceforge.net
Subject: Re: [patch 7/7] uml: retry host close() on EINTR
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On Sat, 10 Sep 2005, Paolo 'Blaisorblade' Giarrusso wrote:
>
> When calling close() on the host, we must retry the operation when we get
> EINTR.

Actually, no.

If close() return EINTR, the file descriptor _will_ have been closed. The
error return just tells you that soem error happened on the file: for
example, in the case of EINTR, the close() may not have flushed all the
pending data synchronously.

Re-doing the close() is the wrong thing to do, since in a threaded 
environment, something else might have opened another file, gotten the 
same file descriptor, and you now close _another_ file.

(Normally, re-doing the close will just return EBADF, of course).

I'm going to drop this patch, but in case you've ever seen a case where 
EINTR actually means that the fd didn't get closed, please holler, and we 
need to fix it.

			Linus
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