From: Christoph Hellwig <hch@lst.de>
To: Matthew Wilcox <willy@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>,
linux-kernel@vger.kernel.org, axboe@kernel.dk,
boaz@plexistor.com, david@fromorbit.com,
linux-arch@vger.kernel.org, arnd@arndb.de,
ross.zwisler@linux.intel.com, linux-nvdimm@ml01.01.org,
benh@kernel.crashing.org, linux-fsdevel@vger.kernel.org,
heiko.carstens@de.ibm.com, tj@kernel.org, paulus@samba.org,
hpa@zytor.com, schwidefsky@de.ibm.com, akpm@linux-foundation.org,
torvalds@linux-foundation.org, mingo@kernel.org
Subject: Re: [PATCH v4 2/9] x86: support kmap_atomic_pfn_t() for persistent memory
Date: Wed, 10 Jun 2015 17:11:00 +0200 [thread overview]
Message-ID: <20150610151100.GA12757@lst.de> (raw)
In-Reply-To: <20150610150334.GK2729@linux.intel.com>
On Wed, Jun 10, 2015 at 11:03:35AM -0400, Matthew Wilcox wrote:
> On Wed, Jun 10, 2015 at 02:12:02PM +0200, Christoph Hellwig wrote:
> > Btw, I don't think this actually is safe without refcounting your kmap
> > structure.
> >
> > The driver model ->remove callback can be called at any time, which
> > will ioremap the memory and remap the kmap structure. But at this
> > point a user might still be using it.
>
> Won't the device data structures be pinned by the refcount on the bdev?
An open filesystem only keeps a reference on the request_queue. The
underlying driver model ->remove method will still be called on
a surprise removal.
next prev parent reply other threads:[~2015-06-10 15:11 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-05 21:19 [PATCH v4 0/9] introduce __pfn_t, evacuate struct page from sgls Dan Williams
2015-06-05 21:19 ` [PATCH v4 1/9] introduce __pfn_t for scatterlists and pmem Dan Williams
2015-06-05 21:37 ` Linus Torvalds
2015-06-05 22:12 ` Dan Williams
2015-06-05 21:19 ` [PATCH v4 2/9] x86: support kmap_atomic_pfn_t() for persistent memory Dan Williams
2015-06-09 6:50 ` Christoph Hellwig
2015-06-10 12:12 ` Christoph Hellwig
2015-06-10 15:03 ` Matthew Wilcox
2015-06-10 15:11 ` Christoph Hellwig [this message]
2015-06-10 15:36 ` Dan Williams
2015-06-10 16:11 ` Christoph Hellwig
2015-06-10 16:17 ` Dan Williams
2015-06-05 21:19 ` [PATCH v4 3/9] dax: drop size parameter to ->direct_access() Dan Williams
2015-06-06 11:37 ` Matthew Wilcox
2015-06-09 6:51 ` Christoph Hellwig
2015-06-05 21:19 ` [PATCH v4 4/9] dax: fix mapping lifetime handling, convert to __pfn_t + kmap_atomic_pfn_t() Dan Williams
2015-06-06 11:58 ` Matthew Wilcox
2015-08-07 23:54 ` Dan Williams
2015-06-08 16:29 ` Elliott, Robert (Server Storage)
2015-06-08 16:36 ` Dan Williams
2015-06-09 6:55 ` Christoph Hellwig
2015-06-05 21:19 ` [PATCH v4 5/9] dma-mapping: allow archs to optionally specify a ->map_pfn() operation Dan Williams
2015-06-05 21:19 ` [PATCH v4 6/9] scatterlist: use sg_phys() Dan Williams
2015-06-09 6:59 ` Christoph Hellwig
2015-06-05 21:19 ` [PATCH v4 7/9] scatterlist: cleanup sg_chain() and sg_unmark_end() Dan Williams
2015-06-05 21:19 ` [PATCH v4 8/9] scatterlist: convert to __pfn_t Dan Williams
2015-06-05 21:19 ` [PATCH v4 9/9] x86: convert dma_map_ops to support mapping a __pfn_t Dan Williams
2015-06-09 6:58 ` Christoph Hellwig
2015-06-09 13:47 ` Konrad Rzeszutek Wilk
2015-06-05 21:23 ` [PATCH v4 0/9] introduce __pfn_t, evacuate struct page from sgls Dan Williams
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=20150610151100.GA12757@lst.de \
--to=hch@lst.de \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=axboe@kernel.dk \
--cc=benh@kernel.crashing.org \
--cc=boaz@plexistor.com \
--cc=dan.j.williams@intel.com \
--cc=david@fromorbit.com \
--cc=heiko.carstens@de.ibm.com \
--cc=hpa@zytor.com \
--cc=linux-arch@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvdimm@ml01.01.org \
--cc=mingo@kernel.org \
--cc=paulus@samba.org \
--cc=ross.zwisler@linux.intel.com \
--cc=schwidefsky@de.ibm.com \
--cc=tj@kernel.org \
--cc=torvalds@linux-foundation.org \
--cc=willy@linux.intel.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).