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[159.2.73.22]) by smtp.gmail.com with ESMTPSA id af79cd13be357-8ddb9833c6asm313552085a.42.2026.04.10.14.49.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 10 Apr 2026 14:49:23 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1wBJj9-0000000GMKd-1fP8; Fri, 10 Apr 2026 18:49:23 -0300 Date: Fri, 10 Apr 2026 18:49:23 -0300 From: Jason Gunthorpe To: Dave Jiang Cc: Richard Cheng , saeedm@nvidia.com, Jonathan.Cameron@huawei.com, linux-kernel@vger.kernel.org, jan@nvidia.com, newtonl@nvidia.com, kristinc@nvidia.com, sreddym@nvidia.com, skomatineni@nvidia.com, vidyas@nvidia.com, kaihengf@nvidia.com, mochs@nvidia.com Subject: Re: [PATCH] fwctl: Fix class init ordering to avoid NULL pointer dereference on device removal Message-ID: <20260410214923.GC3694781@ziepe.ca> References: <20260409051902.40218-1-icheng@nvidia.com> <37f2f122-ec03-462c-82f4-e893f5260274@intel.com> <24bb834c-fb53-4b8a-b053-a18af2bb91cc@intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <24bb834c-fb53-4b8a-b053-a18af2bb91cc@intel.com> On Fri, Apr 10, 2026 at 10:16:19AM -0700, Dave Jiang wrote: > Yeah, I'm just not coming up with a good solution for the > driver-core. I presume that the way it's setup to allow 'sp' to be > NULL because there are scenarios where it is NULL? Not sure if just > allowing the kernel to OOPs on uninitialized knode is fine because > it's a programming error or if that should be handled more > gracefully. The real issue is the fwctl register failed even though the class isn't registered. I didn't try to trace down the details but I do find that a bit surprising the driver core didn't complain during registration Jason