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([2a02:3033:701:244:19c9:79b9:fe6b:6f9]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-48e2582a53fsm3980308f8f.32.2026.10.21.01.01.25 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 21 Oct 2026 01:01:25 -0700 (PDT) Message-ID: Date: Wed, 21 Oct 2026 10:01:24 +0200 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] usb: core: Emit KOBJ_CHANGE on unbound interface To: Fabien Sanglard Cc: Greg Kroah-Hartman , Alan Stern , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org References: <20261012171609.88273-1-sanglardf@google.com> Content-Language: en-US From: Oliver Neukum In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Good morning, On 13.10.26 18:48, Fabien Sanglard wrote: > That said, unifying the behavior upon reset would be elegant. My main > concern is whether some existing udev rules or netlink listeners in > user space might break if we generalize this behavior and start > emitting unexpected CHANGE events for interfaces that successfully > rebound (which already emit UNBIND -> BIND). On a generic note, it seems to me that you are concerned about an unavoidable case. You can check whether an interface is unclaimed. Yet you have no way to ensure that the result of your check is still current and thus valid, at time you act upon it. In other words, you were about to design an interface that is inherently racy. That is not a good idea. If you really, really need to avoid it, you'd have to define a new type of event. Regards Oliver