From: "Koralahalli Channabasappa, Smita" <skoralah@amd.com>
To: dan.j.williams@intel.com,
Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>,
linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org,
nvdimm@lists.linux.dev, linux-fsdevel@vger.kernel.org,
linux-pm@vger.kernel.org
Cc: Alison Schofield <alison.schofield@intel.com>,
Vishal Verma <vishal.l.verma@intel.com>,
Ira Weiny <ira.weiny@intel.com>,
Jonathan Cameron <jonathan.cameron@huawei.com>,
Yazen Ghannam <yazen.ghannam@amd.com>,
Dave Jiang <dave.jiang@intel.com>,
Davidlohr Bueso <dave@stgolabs.net>,
Matthew Wilcox <willy@infradead.org>, Jan Kara <jack@suse.cz>,
"Rafael J . Wysocki" <rafael@kernel.org>,
Len Brown <len.brown@intel.com>, Pavel Machek <pavel@kernel.org>,
Li Ming <ming.li@zohomail.com>,
Jeff Johnson <jeff.johnson@oss.qualcomm.com>,
Ying Huang <huang.ying.caritas@gmail.com>,
Yao Xingtao <yaoxt.fnst@fujitsu.com>,
Peter Zijlstra <peterz@infradead.org>,
Greg KH <gregkh@linuxfoundation.org>,
Nathan Fontenot <nathan.fontenot@amd.com>,
Terry Bowman <terry.bowman@amd.com>,
Robert Richter <rrichter@amd.com>,
Benjamin Cheatham <benjamin.cheatham@amd.com>,
Zhijian Li <lizhijian@fujitsu.com>,
Borislav Petkov <bp@alien8.de>, Ard Biesheuvel <ardb@kernel.org>
Subject: Re: [PATCH v4 4/9] dax/hmem: Defer handling of Soft Reserved ranges that overlap CXL windows
Date: Thu, 11 Dec 2025 15:23:09 -0800 [thread overview]
Message-ID: <34a26e2e-d3f3-4508-94ee-89943144f8fa@amd.com> (raw)
In-Reply-To: <692f6a2035c79_261c1100d2@dwillia2-mobl4.notmuch>
On 12/2/2025 2:37 PM, dan.j.williams@intel.com wrote:
> Smita Koralahalli wrote:
>> From: Dan Williams <dan.j.williams@intel.com>
>>
>> Defer handling of Soft Reserved ranges that intersect CXL windows at
>> probe time. Delay processing until after device discovery so that the
>> CXL stack can publish windows and assemble regions before HMEM claims
>> those address ranges.
>>
>> Add a deferral path that schedules deferred work when HMEM detects a
>> Soft Reserved range intersecting a CXL window during probe. The deferred
>> work runs after probe completes and allows the CXL subsystem to finish
>> resource discovery and region setup before HMEM takes any action.
>>
>> This change does not address region assembly failures. It only delays
>> HMEM handling to avoid prematurely claiming ranges that CXL may own.
>
> No, with the changes it just unconditionally disables dax_hmem in the
> presence of CXL. I do not think these changes can stand alone. It
> probably wants to be folded with patch 5 or something like that.
Sure, will include this with changes suggested in Patch 5.
Thanks
Smita
next prev parent reply other threads:[~2025-12-11 23:23 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-20 3:19 [PATCH v4 0/9] dax/hmem, cxl: Coordinate Soft Reserved handling with CXL and HMEM Smita Koralahalli
2025-11-20 3:19 ` [PATCH v4 1/9] dax/hmem, e820, resource: Defer Soft Reserved insertion until hmem is ready Smita Koralahalli
2025-12-02 22:19 ` dan.j.williams
2025-12-11 23:20 ` Koralahalli Channabasappa, Smita
2025-12-02 23:31 ` Dave Jiang
2025-11-20 3:19 ` [PATCH v4 2/9] dax/hmem: Request cxl_acpi and cxl_pci before walking Soft Reserved ranges Smita Koralahalli
2025-11-20 3:19 ` [PATCH v4 3/9] dax/hmem: Gate Soft Reserved deferral on DEV_DAX_CXL Smita Koralahalli
2025-12-02 23:32 ` Dave Jiang
2025-11-20 3:19 ` [PATCH v4 4/9] dax/hmem: Defer handling of Soft Reserved ranges that overlap CXL windows Smita Koralahalli
2025-12-02 22:37 ` dan.j.williams
2025-12-11 23:23 ` Koralahalli Channabasappa, Smita [this message]
2025-11-20 3:19 ` [PATCH v4 5/9] cxl/region, dax/hmem: Arbitrate Soft Reserved ownership with cxl_regions_fully_map() Smita Koralahalli
2025-12-03 3:50 ` dan.j.williams
2025-12-11 23:42 ` Koralahalli Channabasappa, Smita
2025-11-20 3:19 ` [PATCH v4 6/9] cxl/region: Add register_dax flag to defer DAX setup Smita Koralahalli
2025-11-20 18:17 ` Koralahalli Channabasappa, Smita
2025-11-20 20:21 ` kernel test robot
2025-12-04 0:22 ` dan.j.williams
2025-12-12 19:59 ` Koralahalli Channabasappa, Smita
2025-11-20 3:19 ` [PATCH v4 7/9] cxl/region, dax/hmem: Register cxl_dax only when CXL owns Soft Reserved span Smita Koralahalli
2025-11-20 3:19 ` [PATCH v4 8/9] cxl/region, dax/hmem: Tear down CXL regions when HMEM reclaims Soft Reserved Smita Koralahalli
2025-12-04 0:50 ` dan.j.williams
2025-11-20 3:19 ` [PATCH v4 9/9] dax/hmem: Reintroduce Soft Reserved ranges back into the iomem tree Smita Koralahalli
2025-12-04 0:54 ` dan.j.williams
2025-12-01 19:56 ` [PATCH v4 0/9] dax/hmem, cxl: Coordinate Soft Reserved handling with CXL and HMEM Alison Schofield
2025-12-03 13:35 ` Tomasz Wolski
2025-12-03 22:05 ` dan.j.williams
2025-12-05 2:54 ` Yasunori Gotou (Fujitsu)
2025-12-05 23:04 ` Tomasz Wolski
2025-12-06 0:11 ` dan.j.williams
2025-12-02 6:41 ` dan.j.williams
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