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From: Christoph Hellwig <hch@lst.de>
To: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Al Viro <viro@ZenIV.linux.org.uk>, Christoph Hellwig <hch@lst.de>
Subject: Re: [PATCH 2/6] ERR_PTR: add ERR_OR_0_PTR
Date: Mon, 19 May 2008 07:55:04 +0200	[thread overview]
Message-ID: <20080519055504.GB14902@lst.de> (raw)
In-Reply-To: <1211148067-16130-1-git-send-email-marcin.slusarz@gmail.com>

On Mon, May 19, 2008 at 12:01:07AM +0200, Marcin Slusarz wrote:
> Some codepaths call ERR_PTR with possibly 0 argument, which is not
> a valid errno and rely on conversion from 0 to NULL pointer.
> Add ERR_OR_0_PTR function which accepts errnos and 0 as an argument.

Sorry, no.  ERR_PTR(0) is perfectly valid, you just don't want to return
the actualy value.  E.g. we have a common idiom of:

	some_ptr = ERR_PTR(err);
	if (IS_ERR(some_ptr))
		goto out_handle_err;

and obsfucating this with new syntactic sugar is not a good idea.


  parent reply	other threads:[~2008-05-19  5:55 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-05-11 20:12 [PATCH] let ERR_PTR BUILD_BUG_ON when we know its argument is not a valid errno Marcin Slusarz
2008-05-12 23:38 ` Andrew Morton
2008-05-13 20:18   ` Marcin Slusarz
2008-05-18 21:56     ` [PATCH 0/6] Sanity checks for ERR_PTR argument Marcin Slusarz
2008-05-18 21:56     ` [PATCH 1/6] ERR_PTR: if errno value is known at compile time, make sure it's valid Marcin Slusarz
2008-05-19  6:38       ` Alexey Dobriyan
2008-05-22 16:03         ` Marcin Slusarz
2008-05-18 22:01     ` [PATCH 2/6] ERR_PTR: add ERR_OR_0_PTR Marcin Slusarz
2008-05-18 23:04       ` Johannes Weiner
2008-05-19  5:55       ` Christoph Hellwig [this message]
2008-05-19  6:33         ` Al Viro
2008-05-18 22:01     ` [PATCH 3/6] vfs: open_exec cleanup Marcin Slusarz
2008-05-19  5:53       ` Christoph Hellwig
2008-05-22 15:57         ` Marcin Slusarz
2008-05-18 22:03     ` [PATCH 4/6] procfs: switch ERR_PTR to ERR_OR_0_PTR when "error" might be 0 Marcin Slusarz
2008-05-18 22:03     ` [PATCH 5/6] vfs: fix ERR_PTR abuse in generic_readlink Marcin Slusarz
2008-05-18 22:04     ` [PATCH 6/6] ERR_PTR: warn when ERR_PTR parameter is not errno value Marcin Slusarz
2008-05-18 23:13       ` Johannes Weiner
2008-05-19  6:43         ` Alexey Dobriyan
2008-05-19 12:11           ` Johannes Weiner
2008-05-22 16:08             ` Marcin Slusarz

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