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[142.162.112.119]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-89a65bd318fsm33341196d6.8.2026.03.12.05.57.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 12 Mar 2026 05:57:31 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1w0fbW-00000006fKD-1POa; Thu, 12 Mar 2026 09:57:30 -0300 Date: Thu, 12 Mar 2026 09:57:30 -0300 From: Jason Gunthorpe To: Kuan-Wei Chiu Cc: Philipp Hahn , amd-gfx@lists.freedesktop.org, apparmor@lists.ubuntu.com, bpf@vger.kernel.org, ceph-devel@vger.kernel.org, cocci@inria.fr, dm-devel@lists.linux.dev, dri-devel@lists.freedesktop.org, gfs2@lists.linux.dev, intel-gfx@lists.freedesktop.org, intel-wired-lan@lists.osuosl.org, iommu@lists.linux.dev, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-block@vger.kernel.org, linux-bluetooth@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-clk@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-gpio@vger.kernel.org, linux-hyperv@vger.kernel.org, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org, linux-media@vger.kernel.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, linux-modules@vger.kernel.org, linux-mtd@lists.infradead.org, linux-nfs@vger.kernel.org, linux-omap@vger.kernel.org, linux-phy@lists.infradead.org, linux-pm@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-s390@vger.kernel.org, linux-scsi@vger.kernel.org, linux-sctp@vger.kernel.org, linux-security-module@vger.kernel.org, linux-sh@vger.kernel.org, linux-sound@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-trace-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, ntfs3@lists.linux.dev, samba-technical@lists.samba.org, sched-ext@lists.linux.dev, target-devel@vger.kernel.org, tipc-discussion@lists.sourceforge.net, v9fs@lists.linux.dev Subject: Re: [PATCH 00/61] treewide: Use IS_ERR_OR_NULL over manual NULL check - refactor Message-ID: <20260312125730.GI1469476@ziepe.ca> References: <20260310-b4-is_err_or_null-v1-0-bd63b656022d@avm.de> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Mar 11, 2026 at 02:40:36AM +0800, Kuan-Wei Chiu wrote: > IMHO, the necessity of IS_ERR_OR_NULL() often highlights a confusing or > flawed API design. It usually implies that the caller is unsure whether > a failure results in an error pointer or a NULL pointer. +1 IS_ERR_OR_NULL() should always be looked on with suspicion. Very little should be returning some tri-state 'ERR' 'NULL' 'SUCCESS' pointer. What does the middle condition even mean? IS_ERR_OR_NULL() implies ERR and NULL are semanticly the same, so fix the things to always use ERR. If you want to improve things work to get rid of the NULL checks this script identifies. Remove ERR or NULL because only one can ever happen, or fix the source to consistently return ERR. Jason