From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) (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 EAE6944AB8D for ; Tue, 4 Aug 2026 23:54:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.12 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785887690; cv=none; b=TAA3wlEmydJdX/mONYPbwOxXZeb91LPLuNBSOnxpB25seCwXr/6LOCrTPehfQDTCyhNnXBjinQl2DvvFwWqBM/BdPlcF6PK8hR1yR9g4sF9bGF+sCqk/XcqlZgguhcuBOYT0gQs1yrQiAKR7iEZxEFMdPD6NnMhIgPyyQoL4ZHs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785887690; c=relaxed/simple; bh=dlVfOaW2BcS/8ZscA+AC93RlpoSyCVyt3w8eLMCO4GM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=HwS+60qIBlnGOxp/9wTU/zuLbEPxD0X8oPgfQEGKcUne4DEHYx7ePU3E9o1sVLhdNAPd7MELgNQ0/sa3SiMWFnlZwG8SkEyP6uoGwFfiuJMpnWX5mdVQ0zL3mlaYw9E2DtYwt2uxbCwRW5e0PhHiXwRHgEyNJ347jPteubBzFBU= 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=i5SlhXWz; arc=none smtp.client-ip=192.198.163.12 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="i5SlhXWz" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1785887689; x=1817423689; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=dlVfOaW2BcS/8ZscA+AC93RlpoSyCVyt3w8eLMCO4GM=; b=i5SlhXWzIArhTGERGr8t4bL1n10LVc0QhfvaYGmA+5m2aSRnyKIVpyfP sVR9ZA9ve4ldaqckSupZfb3uQ3AdbhxRh2ns/uIGREtvxLBloqRywJDYH PZu++qfA9bHpK33r04xDyuSjIT/MhKJdOdQe2gXHgN4osre+UjjMb7Pvm w5gR3wCRYwCG9U3dhEhgxH+k4TcB4nAzMBmtWSo6S2TUJtP4OxR54UU8l ZVlcKhmd2AfNw7DdW+Foslb72tubF11zNokPQ9ueyEhACkbkDJnIuxEh+ YZ39AFsGAp9iLQeDjvUSI6NIfqx87DiE0zsnYI9Ha87sR1GTL0XmgRnFx A==; X-CSE-ConnectionGUID: GE8GS4RDS8acy917Gl2vPA== X-CSE-MsgGUID: h7BRameSSnaVvhSMV/KaVQ== X-IronPort-AV: E=McAfee;i="6800,10657,11865"; a="90263298" X-IronPort-AV: E=Sophos;i="6.25,205,1779174000"; d="scan'208";a="90263298" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by fmvoesa106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Aug 2026 16:54:49 -0700 X-CSE-ConnectionGUID: HrYMlWOQSx27UxwSE41lrQ== X-CSE-MsgGUID: OnuhxYahTmaXjbpymYaLhQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,205,1779174000"; d="scan'208";a="257324381" Received: from allen-box.sh.intel.com ([10.239.159.52]) by fmviesa006.fm.intel.com with ESMTP; 04 Aug 2026 16:54:46 -0700 From: Lu Baolu To: Joerg Roedel Cc: ZhaoJinming , Kevin Tian , Dmitry Antipov , Guanghui Feng , Li RongQing , Desnes Nunes , iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v2 11/19] iommu/vt-d: Remove the 'force_on' variable Date: Wed, 5 Aug 2026 07:43:05 +0800 Message-ID: <20260804234314.3087110-12-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260804234314.3087110-1-baolu.lu@linux.intel.com> References: <20260804234314.3087110-1-baolu.lu@linux.intel.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Kevin Tian The force_on variable is now redundant - same information captured by "dmar_policy == DMAR_FORCE_ON". Replace all force_on checks with dmar_policy_force_on(). Signed-off-by: Kevin Tian Signed-off-by: Lu Baolu --- drivers/iommu/intel/iommu.h | 5 +++++ drivers/iommu/intel/iommu.c | 37 +++++++++++++++++-------------------- 2 files changed, 22 insertions(+), 20 deletions(-) diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index dd2376a079b9..40da2ed7e254 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -1394,6 +1394,11 @@ static inline bool dmar_policy_off(void) return dmar_policy < 0; } +static inline bool dmar_policy_force_on(void) +{ + return dmar_policy == DMAR_FORCE_ON; +} + bool dmar_can_force_on(enum dmar_force_on force_on); extern int dmar_disabled; diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 5eb80aeec274..118c62e859fd 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -53,10 +53,9 @@ static int rwbf_quirk; #define rwbf_required(iommu) (rwbf_quirk || cap_rwbf((iommu)->cap)) /* - * set to 1 to panic kernel if can't successfully enable VT-d - * (used when kernel is launched w/ TXT) + * Skip forcing iommu on and avoid tboot-related kernel panics during + * initialization when set to 1 (via intel_iommu=tboot_noforce). */ -static int force_on = 0; int intel_iommu_tboot_noforce; #define ROOT_ENTRY_NR (VTD_PAGE_SIZE/sizeof(struct root_entry)) @@ -1713,7 +1712,7 @@ static int __init init_dmars(void) * we always have to disable PMRs or DMA may fail on * this device */ - if (force_on) + if (dmar_policy_force_on()) iommu_disable_protect_mem_regions(iommu); continue; } @@ -1805,7 +1804,7 @@ static int init_iommu_hw(void) * we always have to disable PMRs or DMA may fail on * this device */ - if (force_on) + if (dmar_policy_force_on()) iommu_disable_protect_mem_regions(iommu); continue; } @@ -1866,7 +1865,7 @@ static void iommu_resume(void *data) unsigned long flag; if (init_iommu_hw()) { - if (force_on) + if (dmar_policy_force_on()) panic("tboot: IOMMU setup failed, DMAR can not resume!\n"); else WARN(1, "IOMMU setup failed, DMAR can not resume!\n"); @@ -2134,7 +2133,7 @@ static int intel_iommu_add(struct dmar_drhd_unit *dmaru) /* * we always have to disable PMRs or DMA may fail on this device */ - if (force_on) + if (dmar_policy_force_on()) iommu_disable_protect_mem_regions(iommu); return 0; } @@ -2487,13 +2486,13 @@ static bool has_external_pci(void) return false; } -static int __init platform_optin_force_iommu(void) +static void __init platform_optin_force_iommu(void) { if (!dmar_platform_optin() || !dmar_can_force_on(DMAR_FORCEON_PLATFORM)) - return 0; + return; if (!has_external_pci()) - return 0; + return; /* * If Intel-IOMMU is disabled by default, we will apply identity @@ -2507,8 +2506,6 @@ static int __init platform_optin_force_iommu(void) /* No concurrent access to dmar_policy at this point. */ dmar_policy = DMAR_FORCE_ON; dmar_disabled = 0; - - return 1; } static int __init probe_acpi_namespace_devices(void) @@ -2548,10 +2545,10 @@ static int __init probe_acpi_namespace_devices(void) return 0; } -static __init int tboot_force_iommu(void) +static __init void tboot_force_iommu(void) { if (!tboot_enabled() || intel_iommu_tboot_noforce) - return 0; + return; if (!dmar_can_force_on(DMAR_FORCEON_TBOOT)) panic("tboot: Failed to force IOMMU on\n"); @@ -2563,8 +2560,6 @@ static __init int tboot_force_iommu(void) dmar_policy = DMAR_FORCE_ON; dmar_disabled = 0; no_iommu = 0; - - return 1; } int __init intel_iommu_init(void) @@ -2577,17 +2572,19 @@ int __init intel_iommu_init(void) * Intel IOMMU is required for a TXT/tboot launch or platform * opt in, so enforce that. */ - force_on = tboot_force_iommu() || platform_optin_force_iommu(); + tboot_force_iommu(); + if (!dmar_policy_force_on()) + platform_optin_force_iommu(); down_write(&dmar_global_lock); if (dmar_table_init()) { - if (force_on) + if (dmar_policy_force_on()) panic("tboot: Failed to initialize DMAR table\n"); goto out_free_dmar; } if (dmar_dev_scope_init() < 0) { - if (force_on) + if (dmar_policy_force_on()) panic("tboot: Failed to initialize DMAR device scope\n"); goto out_free_dmar; } @@ -2641,7 +2638,7 @@ int __init intel_iommu_init(void) ret = init_dmars(); if (ret) { - if (force_on) + if (dmar_policy_force_on()) panic("tboot: Failed to initialize DMARs\n"); pr_err("Initialization failed\n"); goto out_free_dmar; -- 2.43.0