From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) (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 545B9137C37 for ; Tue, 7 Jan 2025 02:19:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736216391; cv=none; b=AjDzmWKpSBGtIVjlSyO7qZXWjfSUJc3J0+Towjg7yG5uXe5+rbMXXqLj4UVaLdC0qtaBUcogRlu/4ea27i9CEVJSV9j8CD9yAq54V2KdZ7bQNJyNprTvc968AweikdJkXSAGERs6tsTq3jk/R2PAaYElYkUvaA4kzwcCr44iSbI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736216391; c=relaxed/simple; bh=FbdsAtUmXdF2u/Yms3KtHtj2wiqxHBg3vTkGayD1J4A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Rx75WLSzXVgI17cgfGkxEUTsjUpEwR32ISeQws7HY3XX004q8izm1VjcXCZUts2lOeIrmh7mTXzQ5Z+8axDEg+zkMTN/Kc7sXgUOrmNEjdD9hbsCG/MKB7qvAnV/n42yToCVhhh5CInTSuffHSKRFeeXF37QnIR5vLxxnfzQ2w4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=n0WYfFob; arc=none smtp.client-ip=192.198.163.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none 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="n0WYfFob" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1736216388; x=1767752388; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FbdsAtUmXdF2u/Yms3KtHtj2wiqxHBg3vTkGayD1J4A=; b=n0WYfFobr3FHTIpdg1NOjAWuDAbC4MCtz6vm6AURkCvCBzy+PdgmA4D7 F3/h0PTMwp6RDuPqIpDgIU26hZ0t0KUt7pmGIAESgVMujT4FqOV8jBo8e fHtGjL+90YA2DNQ7z1xApOPTw1shm/LwS+7YOCzCfXUTMUqyH8EcBB3Up fmiowBR1q4r0iFP6ymh6YZSyZneNUcSku3u9vgTWPfNrixh4UTe9AiBXE RMcx35kE/JiwdXj1dhltz41RLWWD/OC/UR9XqNqQRQ9ScGYdeuwghZC58 t0V+KwmtMEtEK3jOw5dS44X9BXzWxLdGzZ81hQxaUGlq/WBYkdrGjAxae g==; X-CSE-ConnectionGUID: NVCFKmMKSuawahOnDra0Ug== X-CSE-MsgGUID: eBHe+3+zRqigRdcGe7p63g== X-IronPort-AV: E=McAfee;i="6700,10204,11307"; a="47800763" X-IronPort-AV: E=Sophos;i="6.12,294,1728975600"; d="scan'208";a="47800763" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 Jan 2025 18:19:47 -0800 X-CSE-ConnectionGUID: nczGu+jJR+acbLrc0hrEUQ== X-CSE-MsgGUID: 9xHt8pnUTZ+O9e5CFqXntg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.12,294,1728975600"; d="scan'208";a="102442918" Received: from allen-sbox.sh.intel.com ([10.239.159.30]) by orviesa009.jf.intel.com with ESMTP; 06 Jan 2025 18:19:46 -0800 From: Lu Baolu To: Joerg Roedel Cc: Jason Gunthorpe , Kees Bakker , Zhenzhong Duan , iommu@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH 1/5] iommu/vt-d: Avoid use of NULL after WARN_ON_ONCE Date: Tue, 7 Jan 2025 10:17:42 +0800 Message-ID: <20250107021746.6908-2-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250107021746.6908-1-baolu.lu@linux.intel.com> References: <20250107021746.6908-1-baolu.lu@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Kees Bakker There is a WARN_ON_ONCE to catch an unlikely situation when domain_remove_dev_pasid can't find the `pasid`. In case it nevertheless happens we must avoid using a NULL pointer. Signed-off-by: Kees Bakker Link: https://lore.kernel.org/r/20241218201048.E544818E57E@bout3.ijzerbout.nl Signed-off-by: Lu Baolu --- drivers/iommu/intel/iommu.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 79e0da9eb626..8f75c11a3ec4 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4090,13 +4090,14 @@ void domain_remove_dev_pasid(struct iommu_domain *domain, break; } } - WARN_ON_ONCE(!dev_pasid); spin_unlock_irqrestore(&dmar_domain->lock, flags); cache_tag_unassign_domain(dmar_domain, dev, pasid); domain_detach_iommu(dmar_domain, iommu); - intel_iommu_debugfs_remove_dev_pasid(dev_pasid); - kfree(dev_pasid); + if (!WARN_ON_ONCE(!dev_pasid)) { + intel_iommu_debugfs_remove_dev_pasid(dev_pasid); + kfree(dev_pasid); + } } static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid, -- 2.43.0