From patchwork Fri Jul 30 16:45:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12416643 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C867B70 for ; Fri, 30 Jul 2021 16:46:00 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10061"; a="298717469" X-IronPort-AV: E=Sophos;i="5.84,282,1620716400"; d="scan'208";a="298717469" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jul 2021 09:45:59 -0700 X-IronPort-AV: E=Sophos;i="5.84,282,1620716400"; d="scan'208";a="508283326" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.25]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Jul 2021 09:45:59 -0700 Subject: [PATCH] ACPI: NFIT: Fix support for virtual SPA ranges From: Dan Williams To: nvdimm@lists.linux.dev Cc: Jacek Zloch , Lukasz Sobieraj , "Lee, Chun-Yi" , stable@vger.kernel.org, Krzysztof Rusocki , Damian Bassa , vishal.l.verma@intel.com Date: Fri, 30 Jul 2021 09:45:58 -0700 Message-ID: <162766355874.3223041.9582643895337437921.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Fix the NFIT parsing code to treat a 0 index in a SPA Range Structure as a special case and not match Region Mapping Structures that use 0 to indicate that they are not mapped. Without this fix some platform BIOS descriptions of "virtual disk" ranges do not result in the pmem driver attaching to the range. Details: In addition to typical persistent memory ranges, the ACPI NFIT may also convey "virtual" ranges. These ranges are indicated by a UUID in the SPA Range Structure of UUID_VOLATILE_VIRTUAL_DISK, UUID_VOLATILE_VIRTUAL_CD, UUID_PERSISTENT_VIRTUAL_DISK, or UUID_PERSISTENT_VIRTUAL_CD. The critical difference between virtual ranges and UUID_PERSISTENT_MEMORY, is that virtual do not support associations with Region Mapping Structures. For this reason the "index" value of virtual SPA Range Structures is allowed to be 0. If a platform BIOS decides to represent unmapped NVDIMMs with a 0 index in their "SPA Range Structure Index" the driver falsely matches them and may falsely require labels where "virtual disks" are expected to be label-less. I.e. label-less is where the namespace-range == region-range and the pmem driver attaches with no user action to create a namespace. Cc: Jacek Zloch Cc: Lukasz Sobieraj Cc: "Lee, Chun-Yi" Cc: Fixes: c2f32acdf848 ("acpi, nfit: treat virtual ramdisk SPA as pmem region") Reported-by: Krzysztof Rusocki Reported-by: Damian Bassa Signed-off-by: Dan Williams Reviewed-by: Jeff Moyer --- drivers/acpi/nfit/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c index 23d9a09d7060..6f15e56ef955 100644 --- a/drivers/acpi/nfit/core.c +++ b/drivers/acpi/nfit/core.c @@ -3021,6 +3021,8 @@ static int acpi_nfit_register_region(struct acpi_nfit_desc *acpi_desc, struct acpi_nfit_memory_map *memdev = nfit_memdev->memdev; struct nd_mapping_desc *mapping; + if (memdev->range_index == 0 || spa->range_index == 0) + continue; if (memdev->range_index != spa->range_index) continue; if (count >= ND_MAX_MAPPINGS) {