From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 1CF455383; Fri, 17 Jan 2025 01:44:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737078247; cv=none; b=TzhngY5Gt9viSpshxq7/fGdcidsqUvR71fR0IbDs45ilGeB/ydWfSfjbk77/mwTKDqxz8NB6DUPXFCM+eKNmTqbT8TMphvCrCQVYpwr4tU0Yjd62yiwe7ojEuxedLaxPYzKIXSZPIgFb4XKvmdqqWm0B9zPYtMui7wQCcN3kR6o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737078247; c=relaxed/simple; bh=6xzTH+3aaMXmw8yu6wbcyw5/dNk9bdoOWb2rzNoHKoY=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=WqmTk2qOA/6xIWmHasJ3rNuq4ke/gClSkHoqITrx0k6wHl17S0sy/KM+6fIEXVfImf1qFd7W3cbu/z8FdrG5eePacHVbkPLYZq+kNZi8Kjnb82QdwhSYuJLR5+E33Wpve767gnHfi7+ruqZy0o/kgj3SGgnz2+uMNGFqs0VUPVU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YWzdGyik; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YWzdGyik" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F4089C4CEDF; Fri, 17 Jan 2025 01:44:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1737078246; bh=6xzTH+3aaMXmw8yu6wbcyw5/dNk9bdoOWb2rzNoHKoY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=YWzdGyik5Spa2eoyYAkytpkqA8nyMnxM/v/I19eqJZGkm/iA6I+7LnJCCW6f2m3fo eyPoYdy/f4AM5rQSnNwYoz2sg3cKxJqsOZ7LrUuhrA0/sTTWi8r93bfu9YIoGu6kIL iLGW0cI9zfMCQwQ/zbCaJeTEArjVuCdqXi2pIfWnC+KRsHZkHR+zhCIsWqi/PIWbiS q5BHBxK1o3zL2G8gb/79r9zxD/andz3AaQ9Q2xZqxBPnwYhHzLQJKo7i1HEZdUhzsq xgZdeQMEUUkjwKTvQtcTJb8m9IR+AxYP6RwtuuXsGWYeukpdmyW1nGX1p4ZyaBxSdL UyfVRE56zIvHw== Date: Thu, 16 Jan 2025 17:44:05 -0800 From: Jakub Kicinski To: Breno Leitao Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Paolo Abeni , Simon Horman , Jonathan Corbet , Shuah Khan , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, kernel-team@meta.com, max@kutsevol.com, thepacketgeek@gmail.com Subject: Re: [PATCH net-next v2 3/5] netconsole: add support for sysdata and CPU population Message-ID: <20250116174405.20a0e20b@kernel.org> In-Reply-To: <20250115-netcon_cpu-v2-3-95971b44dc56@debian.org> References: <20250115-netcon_cpu-v2-0-95971b44dc56@debian.org> <20250115-netcon_cpu-v2-3-95971b44dc56@debian.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 15 Jan 2025 05:35:20 -0800 Breno Leitao wrote: > + WARN_ON_ONCE(userdata_len + sysdata_len > > + MAX_EXTRADATA_ENTRY_LEN * MAX_EXTRADATA_ITEMS); > + > + /* nt->sysdata_length will be used later to decide if the message > + * needs to be fragmented. > + * userdata_len cannot be used for it, once next sysdata append should > + * start from the same userdata_len location, and only overwrite old > + * sysdata. > + */ > + nt->sysdata_length = sysdata_len; Updating nt-> fields at runtime is something we haven't done before, right? What's the locking? We depend on target_list_lock ? Looks like previously all the data was on the stack, now we have a mix. Maybe we can pack all the bits of state into a struct for easier passing around, but still put it on the stack?