From: Christoph Hellwig <hch@infradead.org>
To: Jacopo Mondi <jacopo+renesas@jmondi.org>
Cc: ysato@users.sourceforge.jp, dalias@libc.org,
thomas.petazzoni@free-electrons.com, robin.murphy@arm.com,
geert@linux-m68k.org, linux-renesas-soc@vger.kernel.org,
linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] sh: mm: Fix unprotected access to struct device
Date: Wed, 18 Apr 2018 10:47:03 +0000 [thread overview]
Message-ID: <20180418104703.GA12462@infradead.org> (raw)
In-Reply-To: <1523972123-5700-1-git-send-email-jacopo+renesas@jmondi.org>
On Tue, Apr 17, 2018 at 03:35:23PM +0200, Jacopo Mondi wrote:
> With commit ce88313069c36eef80f21fd7 ("arch/sh: make the DMA mapping
> operations observe dev->dma_pfn_offset") the generic DMA allocation
> function on which the SH 'dma_alloc_coherent()' function relies on,
> access the 'dma_pfn_offset' field of struct device.
>
> Unfortunately the 'dma_generic_alloc_coherent()' function is called from
> several places with a NULL struct device argument, halting the CPU
> during the boot process.
>
> This patch fixes the issue protecting access to dev->dma_pfn_offset,
> with a trivial check for validity. It also passes a valid 'struct device'
> in the 'platform_resource_setup_memory' function which is the main user
> of 'dma_alloc_coherent()', and inserting a WARN_ON() check to make future
> (and existing) bogus users of this function they're should provide a valid
> 'struct device' whenever possible.
Please fix those callers to not pass a NULL pointer instead.
next prev parent reply other threads:[~2018-04-18 10:47 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-04-17 13:35 [PATCH] sh: mm: Fix unprotected access to struct device Jacopo Mondi
2018-04-17 13:54 ` Thomas Petazzoni
2018-04-17 13:59 ` jacopo mondi
2018-04-20 8:30 ` Christoph Hellwig
2018-04-17 14:04 ` Geert Uytterhoeven
2018-04-17 14:20 ` jacopo mondi
2018-04-18 9:13 ` Sergei Shtylyov
2018-04-18 10:47 ` Christoph Hellwig [this message]
2018-04-18 13:13 ` jacopo mondi
2018-04-20 8:31 ` Christoph Hellwig
2018-04-20 9:59 ` Geert Uytterhoeven
2018-04-20 14:56 ` Rich Felker
2018-05-02 7:41 ` jacopo mondi
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180418104703.GA12462@infradead.org \
--to=hch@infradead.org \
--cc=dalias@libc.org \
--cc=geert@linux-m68k.org \
--cc=jacopo+renesas@jmondi.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
--cc=linux-sh@vger.kernel.org \
--cc=robin.murphy@arm.com \
--cc=thomas.petazzoni@free-electrons.com \
--cc=ysato@users.sourceforge.jp \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).