From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) (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 92351341AB6; Thu, 4 Sep 2025 18:14:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757009660; cv=none; b=Yipl0miklET8xJEJNjmwHom6BvrZJCeZY4W/tpMdYi6xJN/JPEux9AyGuBqpNGNYQEyJh4nA30Bc04UXPgO7XgReroxCK8D8H0AX+9TCAGhn6n05oM/U1pI2SwpKULV7FZ+tItylhYb2UHKa/6j6wHQWt4TzC19GgarQHd4T4fI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757009660; c=relaxed/simple; bh=snRYZy8sFUcGEZgJH9P6mgJNhGmYsmCzIsOzo2eyGW4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=a2vJ1HFSMVfjnV5Q3S1EfvMKOvmPNVjNTlcFJdghqHtpv90zkvCuVYiHgApaY8+yZ5o4P5JBNxX/oblS6Sf41J940ZpOdi1/x/8N8xhhfJ/ZTxb3LpP24l13w/dSzdVpEAMrdACUpMMAjzRxzta9834/9ZWoSBcNoH99kUiF+7w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=Jaw00GqV; arc=none smtp.client-ip=198.175.65.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="Jaw00GqV" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1757009658; x=1788545658; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=snRYZy8sFUcGEZgJH9P6mgJNhGmYsmCzIsOzo2eyGW4=; b=Jaw00GqVNWfQlgJBQsYhi5N2jGUlLg0p0hbxuHBUiIRPyLlMvnvjRK/V F897XlXnTAh0IGECbRrzjkPNGMgJbH5JqdDTFbvyp3wZieXP5pB4MwV0k Q7aIzW9KY0Rnwb8Cbv/qDoIetRTRr4jij45zSuF+nFN3SSnwhY63iu6BY wfdUAAjQPsEhNXNdGadRohmT9ty1bSDi7dK73HmcqgI2+rHS0dj0YF9+n 4rvNm2FHgjc08RtV4HzG9aj1AlDpKEacMKHI0krCSs71BUHBaQtQeB98G 25mfyhqaXxmtC+QlY5GcaNZ4GQbWKLc5yy4qyWHCpd8yJ7uIQ3CtwCyU8 w==; X-CSE-ConnectionGUID: bQP0YyE1T3KLRj1fus8YTw== X-CSE-MsgGUID: avdgIM2GRH+ixkTYZGfj6Q== X-IronPort-AV: E=McAfee;i="6800,10657,11543"; a="76814956" X-IronPort-AV: E=Sophos;i="6.18,239,1751266800"; d="scan'208";a="76814956" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Sep 2025 11:14:18 -0700 X-CSE-ConnectionGUID: uXWQ13oQTYOxPlfW1q2Xow== X-CSE-MsgGUID: vt+G3bBGQMSvNLBiSWtcYA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.18,239,1751266800"; d="scan'208";a="176300742" Received: from cmdeoliv-mobl4.amr.corp.intel.com (HELO [10.125.110.24]) ([10.125.110.24]) by orviesa004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Sep 2025 11:14:16 -0700 Message-ID: <14d94e89-8342-4bd7-9c53-a3b46e22caa7@intel.com> Date: Thu, 4 Sep 2025 11:14:15 -0700 Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 5/6] dax/hmem: Reintroduce Soft Reserved ranges back into the iomem tree To: Smita Koralahalli , 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: Davidlohr Bueso , Jonathan Cameron , Alison Schofield , Vishal Verma , Ira Weiny , Dan Williams , Matthew Wilcox , Jan Kara , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Li Ming , Jeff Johnson , Ying Huang , Yao Xingtao , Peter Zijlstra , Greg KH , Nathan Fontenot , Terry Bowman , Robert Richter , Benjamin Cheatham , PradeepVineshReddy Kodamati , Zhijian Li References: <20250822034202.26896-1-Smita.KoralahalliChannabasappa@amd.com> <20250822034202.26896-6-Smita.KoralahalliChannabasappa@amd.com> Content-Language: en-US From: Dave Jiang In-Reply-To: <20250822034202.26896-6-Smita.KoralahalliChannabasappa@amd.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/21/25 8:42 PM, Smita Koralahalli wrote: > Reworked from a patch by Alison Schofield > > Reintroduce Soft Reserved range into the iomem_resource tree for dax_hmem > to consume. > > This restores visibility in /proc/iomem for ranges actively in use, while > avoiding the early-boot conflicts that occurred when Soft Reserved was > published into iomem before CXL window and region discovery. > > Link: https://lore.kernel.org/linux-cxl/29312c0765224ae76862d59a17748c8188fb95f1.1692638817.git.alison.schofield@intel.com/ > Co-developed-by: Alison Schofield > Signed-off-by: Alison Schofield > Signed-off-by: Smita Koralahalli Reviewed-by: Dave Jiang > --- > drivers/dax/hmem/hmem.c | 38 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 38 insertions(+) > > diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c > index 90978518e5f4..24a6e7e3d916 100644 > --- a/drivers/dax/hmem/hmem.c > +++ b/drivers/dax/hmem/hmem.c > @@ -93,6 +93,40 @@ static void process_defer_work(struct work_struct *_work) > walk_hmem_resources(&pdev->dev, handle_deferred_cxl); > } > > +static void remove_soft_reserved(void *data) > +{ > + struct resource *r = data; > + > + remove_resource(r); > + kfree(r); > +} > + > +static int add_soft_reserve_into_iomem(struct device *host, > + const struct resource *res) > +{ > + struct resource *soft = kzalloc(sizeof(*soft), GFP_KERNEL); > + int rc; > + > + if (!soft) > + return -ENOMEM; > + > + *soft = DEFINE_RES_NAMED_DESC(res->start, (res->end - res->start + 1), > + "Soft Reserved", IORESOURCE_MEM, > + IORES_DESC_SOFT_RESERVED); > + > + rc = insert_resource(&iomem_resource, soft); > + if (rc) { > + kfree(soft); > + return rc; > + } > + > + rc = devm_add_action_or_reset(host, remove_soft_reserved, soft); > + if (rc) > + return rc; > + > + return 0; > +} > + > static int hmem_register_device(struct device *host, int target_nid, > const struct resource *res) > { > @@ -125,6 +159,10 @@ static int hmem_register_device(struct device *host, int target_nid, > IORES_DESC_SOFT_RESERVED); > if (rc != REGION_INTERSECTS) > return 0; > + > + rc = add_soft_reserve_into_iomem(host, res); > + if (rc) > + return rc; > #else > rc = region_intersects(res->start, resource_size(res), IORESOURCE_MEM, > IORES_DESC_SOFT_RESERVED);