From: Andrew Morton <akpm@linux-foundation.org>
To: Huang Ying <ying.huang@intel.com>
Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org,
linux-cxl@vger.kernel.org,
Dan Williams <dan.j.williams@intel.com>,
David Hildenbrand <david@redhat.com>,
Davidlohr Bueso <dave@stgolabs.net>,
Jonathan Cameron <jonathan.cameron@huawei.com>,
Dave Jiang <dave.jiang@intel.com>,
Alison Schofield <alison.schofield@intel.com>,
Vishal Verma <vishal.l.verma@intel.com>,
Ira Weiny <ira.weiny@intel.com>,
Alistair Popple <apopple@nvidia.com>,
Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
Bjorn Helgaas <bhelgaas@google.com>, Baoquan He <bhe@redhat.com>
Subject: Re: [PATCH -v3 1/3] resource: Fix region_intersects() vs add_memory_driver_managed()
Date: Sat, 7 Sep 2024 20:24:58 -0700 [thread overview]
Message-ID: <20240907202458.dfe90bfee071021706af91eb@linux-foundation.org> (raw)
In-Reply-To: <20240906030713.204292-2-ying.huang@intel.com>
On Fri, 6 Sep 2024 11:07:11 +0800 Huang Ying <ying.huang@intel.com> wrote:
> On a system with CXL memory, the resource tree (/proc/iomem) related
> to CXL memory may look like something as follows.
>
> 490000000-50fffffff : CXL Window 0
> 490000000-50fffffff : region0
> 490000000-50fffffff : dax0.0
> 490000000-50fffffff : System RAM (kmem)
>
> Because drivers/dax/kmem.c calls add_memory_driver_managed() during
> onlining CXL memory, which makes "System RAM (kmem)" a descendant of
> "CXL Window X". This confuses region_intersects(), which expects all
> "System RAM" resources to be at the top level of iomem_resource. This
> can lead to bugs.
>
> ...
>
> Fixes: c221c0b0308f ("device-dax: "Hotplug" persistent memory for use like normal RAM")
Do you believe this should be fixed in earlier (-stable) kernels?
next prev parent reply other threads:[~2024-09-08 3:25 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-09-06 3:07 [PATCH -v3 0/3] " Huang Ying
2024-09-06 3:07 ` [PATCH -v3 1/3] " Huang Ying
2024-09-08 3:24 ` Andrew Morton [this message]
2024-09-09 0:57 ` Huang, Ying
2024-09-06 3:07 ` [PATCH -v3 2/3] resource: Make alloc_free_mem_region() works for iomem_resource Huang Ying
2024-09-09 7:04 ` David Hildenbrand
2024-09-09 7:07 ` Huang, Ying
2024-09-09 8:04 ` David Hildenbrand
2024-09-06 3:07 ` [PATCH -v3 3/3] resource, kunit: Add test case for region_intersects() Huang Ying
2024-09-29 19:45 ` Kees Bakker
2024-09-30 0:53 ` Huang, Ying
2024-09-30 17:36 ` Kees Bakker
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=20240907202458.dfe90bfee071021706af91eb@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=alison.schofield@intel.com \
--cc=andriy.shevchenko@linux.intel.com \
--cc=apopple@nvidia.com \
--cc=bhe@redhat.com \
--cc=bhelgaas@google.com \
--cc=dan.j.williams@intel.com \
--cc=dave.jiang@intel.com \
--cc=dave@stgolabs.net \
--cc=david@redhat.com \
--cc=ira.weiny@intel.com \
--cc=jonathan.cameron@huawei.com \
--cc=linux-cxl@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=vishal.l.verma@intel.com \
--cc=ying.huang@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