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From: Al Viro <viro@zeniv.linux.org.uk>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-fsdevel@vger.kernel.org, torvalds@linux-foundation.org
Subject: Re: [PATCH 2/4] fs: add support for LOOKUP_NONBLOCK
Date: Wed, 16 Dec 2020 02:43:15 +0000	[thread overview]
Message-ID: <20201216024315.GJ3579531@ZenIV.linux.org.uk> (raw)
In-Reply-To: <20201214191323.173773-3-axboe@kernel.dk>

On Mon, Dec 14, 2020 at 12:13:22PM -0700, Jens Axboe wrote:
> @@ -3140,6 +3149,12 @@ static const char *open_last_lookups(struct nameidata *nd,
>  			return ERR_CAST(dentry);
>  		if (likely(dentry))
>  			goto finish_lookup;
> +		/*
> +		 * We can't guarantee nonblocking semantics beyond this, if
> +		 * the fast lookup fails.
> +		 */
> +		if (nd->flags & LOOKUP_NONBLOCK)
> +			return ERR_PTR(-EAGAIN);
>  
>  		BUG_ON(nd->flags & LOOKUP_RCU);

That can't be right - we already must have removed LOOKUP_RCU here
(see BUG_ON() right after that point).  What is that test supposed
to catch?

What am I missing here?

  parent reply	other threads:[~2020-12-16  2:44 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-14 19:13 [PATCHSET v3 0/4] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK Jens Axboe
2020-12-14 19:13 ` [PATCH 1/4] fs: make unlazy_walk() error handling consistent Jens Axboe
2020-12-14 19:13 ` [PATCH 2/4] fs: add support for LOOKUP_NONBLOCK Jens Axboe
2020-12-15 12:24   ` Matthew Wilcox
2020-12-15 15:29     ` Jens Axboe
2020-12-15 15:33       ` Matthew Wilcox
2020-12-15 15:37         ` Jens Axboe
2020-12-15 16:08           ` Jens Axboe
2020-12-15 16:14             ` Jens Axboe
2020-12-15 18:29             ` Linus Torvalds
2020-12-15 18:44               ` Jens Axboe
2020-12-15 18:47                 ` Linus Torvalds
2020-12-15 19:03                   ` Jens Axboe
2020-12-15 19:32                     ` Linus Torvalds
2020-12-15 19:38                       ` Jens Axboe
2020-12-16  2:36   ` Al Viro
2020-12-16  3:30     ` Jens Axboe
2020-12-16  2:43   ` Al Viro [this message]
2020-12-16  3:32     ` Jens Axboe
2020-12-14 19:13 ` [PATCH 3/4] fs: expose LOOKUP_NONBLOCK through openat2() RESOLVE_NONBLOCK Jens Axboe
2020-12-15 22:25   ` Dave Chinner
2020-12-15 22:31     ` Linus Torvalds
2020-12-15 23:25       ` Jens Axboe
2020-12-16  2:37   ` Al Viro
2020-12-16  3:39     ` Linus Torvalds
2020-12-14 19:13 ` [PATCH 4/4] io_uring: enable LOOKUP_NONBLOCK path resolution for filename lookups Jens Axboe
2020-12-15  3:06 ` [PATCHSET v3 0/4] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK Linus Torvalds
2020-12-15  3:18   ` Jens Axboe
2020-12-15  6:11 ` Al Viro
2020-12-15 15:29   ` Jens Axboe
2021-01-04  5:31 ` Al Viro
2021-01-04 14:43   ` Jens Axboe
2021-01-04 16:54     ` Al Viro
2021-01-04 17:03       ` Jens Axboe
     [not found] ` <m1lfbrwrgq.fsf@fess.ebiederm.org>
2021-02-14 16:38   ` [PATCHSET v3 0/4] fs: Support for LOOKUP_NONBLOCK / RESOLVE_NONBLOCK (Insufficiently faking current?) Jens Axboe
2021-02-14 20:30     ` Linus Torvalds
2021-02-14 21:24       ` Al Viro
2021-02-15 18:07       ` Eric W. Biederman
2021-02-15 18:24         ` Jens Axboe
2021-02-15 21:09           ` Jens Axboe
2021-02-15 22:41             ` Eric W. Biederman
2021-02-16  2:41               ` Jens Axboe
2021-02-17  1:18                 ` Jens Axboe
2021-02-17  1:26                   ` Jens Axboe
2021-02-17  3:11                     ` Jens Axboe
2021-02-15 17:56     ` Eric W. Biederman

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