From: Matthew Wilcox <willy@infradead.org>
To: void0red <void0red@gmail.com>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] xa_load() needs a NULL check before locking check
Date: Wed, 15 Feb 2023 13:31:39 +0000 [thread overview]
Message-ID: <Y+zeu658Vi7boyxZ@casper.infradead.org> (raw)
In-Reply-To: <20230215131417.150170-1-void0red@gmail.com>
On Wed, Feb 15, 2023 at 09:14:17PM +0800, void0red wrote:
> folio = xa_load(&ractl->mapping->i_pages, ractl->_index);
> + if (!folio) {
> + VM_BUG_ON(!folio);
> + return NULL;
> + }
> VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
Why does this need to happen? The caller has inserted all these folios
into the xarray. They're locked, so they can't be removed. If they're
not there, something has gone horribly wrong and crashing is a good
response.
> ractl->_batch_count = folio_nr_pages(folio);
>
> --
> 2.34.1
>
prev parent reply other threads:[~2023-02-15 13:32 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-02-15 13:14 [PATCH] xa_load() needs a NULL check before locking check void0red
2023-02-15 13:31 ` Matthew Wilcox [this message]
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