From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) (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 D94C12E9ECE for ; Wed, 19 Nov 2025 09:29:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763544569; cv=none; b=sb2QxbPsL1OKrpHWQmyvM1Z4Wldp0RCzclMJbCHxI/DmSQa+h6qy0R61PUv6LsILCzB9z8LwvlmYGe7oSCGzT8h8cPccHKnTkml9/Fieg1PSRQQ/ziGP/qXGVinGaUUN9f25lGFj/TSvGR5tXW0xeNVh3etLmta64Vo2AF9NSnY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763544569; c=relaxed/simple; bh=HYhU1UvsaMo23P6j6sR6QJircnjXsWgiOTeLBE3hddE=; h=Message-ID:Date:MIME-Version:Cc:Subject:To:References:From: In-Reply-To:Content-Type; b=EcPcmlosyZGpAcNPZbwIzVhTDElrkXq3hPKmHe+YzRHKVqLCIVjIB1CIf03T99p1Y5eW3rxtUc9Wt0cRjMgL2zHmMGvjLLIfKvlS62gUbA8Ih9/pESGfAXLlWURUcn2ygyJAjzfBoHTuphCZac9mvIY8yTF7OgKhjxUuh75aHx4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=ZCkV7Z5/; arc=none smtp.client-ip=198.175.65.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="ZCkV7Z5/" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1763544567; x=1795080567; h=message-id:date:mime-version:cc:subject:to:references: from:in-reply-to:content-transfer-encoding; bh=HYhU1UvsaMo23P6j6sR6QJircnjXsWgiOTeLBE3hddE=; b=ZCkV7Z5/nQMHXJg5XtpXcJMySblPV0/wjglarLbLKUlD/96FOV6dmite TuUKbshatMhy0DHj+Yel7QGTpX/td8RRTggiNzmJGaQp4HQ8aSwPGAAiV fhiJa0YP0lHPWZLELNfjX2mre8n7UovvjaoyRX4XUwuPlPNPOdwi5xiBS x4l/OEHpIRAbZUX+gW/OmR2ChatY/4F/6QwkLnjh9w/ARfHSIs0+cap76 rQ8+uFKs3bRuS+l+yjxKDTYplDwB/7pezLJut+IQYAeDU/5AKkFyDPHQc IH6IlhHOy0Q8ZOSg3UoyHRuPHF7jpRZMz9dS/3vPEY7QNw3h3CRxhPsFq w==; X-CSE-ConnectionGUID: 9JbvYIkeRQWicdLxk3gubg== X-CSE-MsgGUID: QQCmsv42Qky6K05J4+gzLQ== X-IronPort-AV: E=McAfee;i="6800,10657,11617"; a="65520104" X-IronPort-AV: E=Sophos;i="6.19,315,1754982000"; d="scan'208";a="65520104" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2025 01:29:27 -0800 X-CSE-ConnectionGUID: PLsjaoNyQVqLBN2WDdjcJQ== X-CSE-MsgGUID: Qoc75SQWQNueevvM4f8ctg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,315,1754982000"; d="scan'208";a="196136897" Received: from blu2-mobl.ccr.corp.intel.com (HELO [10.124.246.21]) ([10.124.246.21]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Nov 2025 01:29:24 -0800 Message-ID: <8648735e-324d-4951-96a8-6276503fc8c9@linux.intel.com> Date: Wed, 19 Nov 2025 17:29:21 +0800 Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Cc: baolu.lu@linux.intel.com, "intel-gfx@lists.freedesktop.org" , "intel-xe@lists.freedesktop.org" , Lucas De Marchi , "Kurmi, Suresh Kumar" , "Saarinen, Jani" , matthew.auld@intel.com, iommu@lists.linux.dev Subject: Re: REGRESSION on linux-next (next-20251106) To: Jason Gunthorpe , "Borah, Chaitanya Kumar" References: <4f15cf3b-6fad-4cd8-87e5-6d86c0082673@intel.com> <20251118012944.GA60885@nvidia.com> <20251118161341.GC90703@nvidia.com> Content-Language: en-US From: Baolu Lu In-Reply-To: <20251118161341.GC90703@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 11/19/2025 12:13 AM, Jason Gunthorpe wrote: >> Also, the tests fail consistently and are not sporadic. > From these logs I see the below fragment, noting this: > > gem_exec_gttfil-1010 [004] .N... 50.126420: map: IOMMU: iova=0x00003fffffc00000 - 0x0000400000000000 paddr=0x00000001b9400000 size=4194304 > ^^^^^^^^^^^^^^^^^^^ > Which is the high IOVA.. It has bit 45 set. I fed this mapping into > the kunit and it does map successfully. > > It is not high enough to get into anything special about sign extend, > the driver sets: > > if (cap_fl5lp_support(iommu->cap)) > cfg.common.hw_max_vasz_lg2 = 57; > else > cfg.common.hw_max_vasz_lg2 = 48; > > Maybe this code is wrong? Baolu what did you get for this log: > > [ 50.126166] i915 0000:00:02.0: Using 46-bit DMA addresses > > In your force second stage test? Is it 46? Second stage uses different > code to compute vasz_lg2 and is sensitive to magw: > > if (mgaw >= 48 && (sagaw & BIT(3))) > return min(57, mgaw); > else if (mgaw >= 39 && (sagaw & BIT(2))) > return min(48, mgaw); > else if (mgaw >= 30 && (sagaw & BIT(1))) > return min(39, mgaw); > > Maybe this is the issue? When first stage translation is used, cfg.common.hw_max_vasz_lg2 = 48 When second stage translation is used, cfg.common.hw_max_vasz_lg2 = 42 Interesting thing is if I hardcode cfg.common.hw_max_vasz_lg2 = 42 for the first stage translation, it works. The only change that I have made to achieve this likes below: diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 2d2f64ce2bc6..a505bba8dcc7 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -2813,10 +2813,13 @@ intel_iommu_domain_alloc_first_stage(struct device *dev, if (IS_ERR(dmar_domain)) return ERR_CAST(dmar_domain); +#if 0 if (cap_fl5lp_support(iommu->cap)) cfg.common.hw_max_vasz_lg2 = 57; else cfg.common.hw_max_vasz_lg2 = 48; +#endif + cfg.common.hw_max_vasz_lg2 = 42; cfg.common.hw_max_oasz_lg2 = 52; cfg.common.features = BIT(PT_FEAT_SIGN_EXTEND) | BIT(PT_FEAT_FLUSH_RANGE); Thanks, baolu