From: Christoph Hellwig <hch@lst.de>
To: Mike Rapoport <rppt@kernel.org>
Cc: linux-arch@vger.kernel.org,
Darren Stevens <darren@stevens-zone.net>,
linux-kernel@vger.kernel.org, Mike Rapoport <rppt@linux.ibm.com>,
linux-mm@kvack.org, iommu@lists.linux-foundation.org,
Rob Herring <robh+dt@kernel.org>,
Paul Mackerras <paulus@samba.org>,
mad skateman <madskateman@gmail.com>,
Christian Zigotzky <chzigotzky@xenosoft.de>,
linuxppc-dev@lists.ozlabs.org, Christoph Hellwig <hch@lst.de>,
Nicolas Saenz Julienne <nsaenzjulienne@suse.de>,
Robin Murphy <robin.murphy@arm.com>
Subject: Re: [PATCH] powerpc: ensure that swiotlb buffer is allocated from low memory
Date: Wed, 4 Dec 2019 14:56:32 +0100 [thread overview]
Message-ID: <20191204135632.GA31262@lst.de> (raw)
In-Reply-To: <20191204123524.22919-1-rppt@kernel.org>
On Wed, Dec 04, 2019 at 02:35:24PM +0200, Mike Rapoport wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
>
> Some powerpc platforms (e.g. 85xx) limit DMA-able memory way below 4G. If a
> system has more physical memory than this limit, the swiotlb buffer is not
> addressable because it is allocated from memblock using top-down mode.
>
> Force memblock to bottom-up mode before calling swiotlb_init() to ensure
> that the swiotlb buffer is DMA-able.
>
> Link: https://lkml.kernel.org/r/F1EBB706-73DF-430E-9020-C214EC8ED5DA@xenosoft.de
> Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
next prev parent reply other threads:[~2019-12-04 14:02 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-04 12:35 [PATCH] powerpc: ensure that swiotlb buffer is allocated from low memory Mike Rapoport
2019-12-04 13:56 ` Christoph Hellwig [this message]
2019-12-09 5:43 ` Michael Ellerman
2019-12-09 7:54 ` Mike Rapoport
2019-12-18 4:05 ` Michael Ellerman
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=20191204135632.GA31262@lst.de \
--to=hch@lst.de \
--cc=chzigotzky@xenosoft.de \
--cc=darren@stevens-zone.net \
--cc=iommu@lists.linux-foundation.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=madskateman@gmail.com \
--cc=nsaenzjulienne@suse.de \
--cc=paulus@samba.org \
--cc=robh+dt@kernel.org \
--cc=robin.murphy@arm.com \
--cc=rppt@kernel.org \
--cc=rppt@linux.ibm.com \
/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).