From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC13135E1A9 for ; Thu, 28 May 2026 20:24:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779999850; cv=none; b=sl665iJwqwfNxfH3PHJXU6dIVC6hB++5752gFEBvLvCqI+XYy2FxKuHtsztzdrUb5d5UfGQ5msYzBBf5FrnfvdvytR2r70YHTBSm8M8Bhcimc1QxqySA3a5n5t01CGwf4kkERoE+VrZhzP3+f6fMHDuc2mUMppsHZcMTYX6VzJ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779999850; c=relaxed/simple; bh=ylHhsRCHAqSMh1pS6GMlC808waOAu3ILm6CtLVqC5hg=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=AhCtxQs0T7Yyqmf9dE+oKms7XJhnSUuOWIQbXcJ9ovAK5szcQ0Fdczl0NXvD34OQUEDjLcpNuI8HeDgxcfcyb2psHKMt9wIfAFfXmpx66Y7Z5Xz/fxOTS2qRmYpgUQgAI4ZQ2OSyBHK3JDJ8nhp/Bgpr34kRx0sb/fddrcbAJjY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--praan.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=tmLE3FNf; arc=none smtp.client-ip=209.85.214.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--praan.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tmLE3FNf" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-2babbeff9e4so146141905ad.0 for ; Thu, 28 May 2026 13:24:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1779999848; x=1780604648; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=Q7UJLNVkpdPww3mteKfmSVmHt+OJdAAQ7hsDxELrWtY=; b=tmLE3FNfR90yjcBQHC+yvKwkbgPdmJCNWlL0dymh+Hr2QCf1obCTMSzAKmtRCK+Dx9 FPCIXWg8iJTzu+gM2VXNQ7MzsNvlDTYTJH5+wQdEEazEpU8EMGlK/y7+G5ZJ8/qX8ig/ y1BkaL5VU9esPPViojFEsLh4pnQ2YqDFbV3t6Pd6GAjPlIckYOjSckrgOW1jrZcsfd3e yeMs57bTZzG7uI9jWtWqH3JmqdK9Q8dFHmNDDA2KIiKUwcVRRGGrPHhYAA5GgIfR4pAd wKyURDAbxI1PtpSvDFts3sKSkFR50HUABr1FSPig8+ZAnvYZ2iQ9H9Q5i/ZwhlNUX8/E 3EGw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1779999848; x=1780604648; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=Q7UJLNVkpdPww3mteKfmSVmHt+OJdAAQ7hsDxELrWtY=; b=U48EJNYLZ7O+hztTsE4TuxEn9awoWLEXX8ExCO5oaNz++VP+e+0kazXh8MNAMKyB+d EjjBcwIc0/GzJORNZZKERCbF+F+RVzL1HjqVnGmwWDiUHnPs0W4alyNg6k5e7xTeQr3n EwEwKLWSKnM30+X+BvUc8okxdhtMOKl2yBQu10TSoWY3PQS8gsyPhZhR1O5SVjJcttyl QEZiwjDqDaU7zfv+iK5Ls9/0lM3oWsVxy63qbW8ZgQx/ZYeCTcqj+9MuhfaO+sEASazd rRjYsOUGy7zf2ZddYE5MYgbsoJBSkmn0Eg0KyzxFlHXm9EwvvVZL1/WDoP6xDGPORufr LH/Q== X-Forwarded-Encrypted: i=1; AFNElJ9HguEzO9qTxVoUFkDTUMNYPPJLto0BChDjNxxxoUKCR05BqdKmDt12hvRfHvwnwChbM/sV2Do66TBS3l4=@vger.kernel.org X-Gm-Message-State: AOJu0Yyp85iQz3Xm2gQnn3tTvEDkOh4H/pklWVuRE115+UkokFR3ew1c aQlx7eofwtkL/FbLrrNkkGGQfjJAzI4+AkH8Puu/HMCXvk7rt4nAqhxiJSBoq4yHWH1Mukjp6zF 7qQ== X-Received: from pllh12.prod.google.com ([2002:a17:902:748c:b0:2bf:8c:2de]) (user=praan job=prod-delivery.src-stubby-dispatcher) by 2002:a17:903:fa3:b0:2bc:8e7d:3dce with SMTP id d9443c01a7336-2bf1ffee251mr1653365ad.27.1779999847992; Thu, 28 May 2026 13:24:07 -0700 (PDT) Date: Thu, 28 May 2026 20:23:52 +0000 In-Reply-To: <20260528202353.3422206-1-praan@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260528202353.3422206-1-praan@google.com> X-Mailer: git-send-email 2.54.0.823.g6e5bcc1fc9-goog Message-ID: <20260528202353.3422206-7-praan@google.com> Subject: [PATCH v5 6/7] iommu/vt-d: Fail probe on ATS configuration failure From: Pranjal Shrivastava To: iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Joerg Roedel , Will Deacon , Bjorn Helgaas , David Woodhouse , Lu Baolu , Robin Murphy , Suravee Suthikulpanit , Jason Gunthorpe , Nicolin Chen , David Matlack , Samiullah Khawaja , Daniel Mentz , Pasha Tatashin , Mostafa Saleh , Pranjal Shrivastava Content-Type: text/plain; charset="UTF-8" Update the Intel VT-d driver to handle ATS configuration and enablement more strictly. Specifically, update the device probe to fail if pci_prepare_ats() returns an error. This ensures that any ATS-capable master reaching the attach phase is guaranteed to have a valid config. Additionally, update iommu_enable_pci_ats() to WARN() if pci_enable_ats fails. Since earlier checks in the probe phase preclude config-related failures, any failure during hardware enablement is considered a kernel bug. Signed-off-by: Pranjal Shrivastava --- drivers/iommu/intel/iommu.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index ed6d3a0203f5..f13da16717fe 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -876,8 +876,14 @@ static void iommu_enable_pci_ats(struct device_domain_info *info) if (!pci_ats_page_aligned(pdev)) return; - if (!pci_enable_ats(pdev, VTD_PAGE_SHIFT)) - info->ats_enabled = 1; + /* + * pci_enable_ats() should not fail here because earlier checks + * have already verified support and configuration. + */ + if (WARN_ON(pci_enable_ats(pdev, VTD_PAGE_SHIFT))) + return; + + info->ats_enabled = 1; } static void iommu_disable_pci_ats(struct device_domain_info *info) @@ -3292,7 +3298,10 @@ static struct iommu_device *intel_iommu_probe_device(struct device *dev) dev_iommu_priv_set(dev, info); if (pdev && pci_ats_supported(pdev)) { - pci_prepare_ats(pdev, VTD_PAGE_SHIFT); + ret = pci_prepare_ats(pdev, VTD_PAGE_SHIFT); + if (ret) + goto free; + ret = device_rbtree_insert(iommu, info); if (ret) goto free; -- 2.54.0.823.g6e5bcc1fc9-goog