From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A8728C982FA for ; Tue, 22 Sep 2026 13:16:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=CpoW39srNxONPYDDUz/TIq2+ZKIxJUqkkB951WdQmPQ=; b=T6w9uO3TH6xjfD2O6IQxr2Rbya 2/91p2gJ5sA/xGfvcn1yWMZcGgHtsb8IBehRe/R12msfDVqUo2nolPIYkEE71yAt7gi/WVWgHmQop GYCElOQGv+3lAw8Aw8IIhNJdi4LPhO8uxLGVbAMjr4hr8jtQ+23gmbytcFR4Gr9/yAYk+SjZXrnMy D3XOFwpVZzQMMHrLch09ZbWCVwvMuL68wKvRGASuNSXAPYSvXTgGYvbnn6BMKiKDh+I8Q8d2P/Ke4 5KYDtB3zQ7ngSN8poNOuPvCI2zfqErf/r1RH7Xz5IL9TA1k2OwrYC5XUmLjn1YKm/50eJrpkOOlG4 WmG5enTg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x90Lx-00000005UFC-1foZ; Tue, 22 Sep 2026 13:16:09 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1x90Lv-00000005UE2-2ue0 for linux-arm-kernel@lists.infradead.org; Tue, 22 Sep 2026 13:16:07 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id E27D160200; Tue, 22 Sep 2026 13:16:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CDD861F000FF; Tue, 22 Sep 2026 13:16:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790082966; bh=CpoW39srNxONPYDDUz/TIq2+ZKIxJUqkkB951WdQmPQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=Q/dBf3NT/Ww+wRcc5uIHgrhtruBIFGlacnFvR7ih8VMAa7hijobiF9dvVF7dhvzZl n39/4D1yuLsOy1Ul9HczA19TRaq0OArc3EocFRog4HWjQg46B93Jsnz1nVFzMJ4zNN ELWifKxNMlpGjDhfVWJ2HyvpFVRg3yFsj+h+VfwlDBPTFcnhF6kPqgwDXAO3WkEeG1 ei10QNgeiD1sj5fFTk7IO75osGIsVO0jTCdukJ30XsTym+1VUSNjAnyy3B+RJKXhm9 b3/iN7ikP8P4ZLatk5n9VpJzC1lCEd6+fobw95uX8hsZbBZ38q4WTrUu+zjnYXqIbz TLzAQpbyGxjlQ== Message-ID: <2135509e-2689-4258-ab00-011d47f4b172@kernel.org> Date: Tue, 22 Sep 2026 15:15:55 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v12 02/25] firmware: arm_scmi: Allow registration of unknown-size events/reports To: Cristian Marussi , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, arm-scmi@vger.kernel.org, linux-doc@vger.kernel.org Cc: sudeep.holla@kernel.org, james.quinlan@broadcom.com, f.fainelli@gmail.com, vincent.guittot@linaro.org, etienne.carriere@st.com, peng.fan@oss.nxp.com, michal.simek@amd.com, d-gole@ti.com, jic23@kernel.org, elif.topuz@arm.com, lukasz.luba@arm.com, philip.radford@arm.com, souvik.chakravarty@arm.com, leitao@kernel.org, kas@kernel.org, puranjay@kernel.org, usama.arif@linux.dev, kernel-team@meta.com, Jonathan Cameron References: <20260920091928.2014972-1-cristian.marussi@arm.com> <20260920091928.2014972-3-cristian.marussi@arm.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 9/20/26 11:19, Cristian Marussi wrote: > Allow protocols to register events with build-time unknown sizes: such > events can be declared zero-sized and let the core SCMI stack perform the > needed safe-net boundary checks based on the configured transport size. ok, so we have a maximum message size defined by the transport. We'll use that as payload size, and the report size just gets the additional ktime_t. > pd = scmi_allocate_registered_events_desc(ni, proto_id, ee->queue_sz, > @@ -807,7 +821,8 @@ int scmi_register_protocol_events(const struct scmi_handle *handle, u8 proto_id, > mutex_init(&r_evt->sources_mtx); > > r_evt->report = devm_kzalloc(ni->handle->dev, > - evt->max_report_sz, GFP_KERNEL); > + evt->max_report_sz ?: max_report_sz, Having two similarly named variables is a bit confusing. I wonder if you can somehow make it clearer in the latter case that it is the max_report_sz according to the transport. > + GFP_KERNEL); > if (!r_evt->report) > return -ENOMEM; > > diff --git a/drivers/firmware/arm_scmi/notify.h b/drivers/firmware/arm_scmi/notify.h > index f18f98c5ab3b..c2eb4844c7db 100644 > --- a/drivers/firmware/arm_scmi/notify.h > +++ b/drivers/firmware/arm_scmi/notify.h > @@ -18,8 +18,12 @@ > /** > * struct scmi_event - Describes an event to be supported > * @id: Event ID > - * @max_payld_sz: Max possible size for the payload of a notification message > - * @max_report_sz: Max possible size for the report of a notification message > + * @max_payld_sz: Max possible size for the payload of a notification message. > + * Set to zero to use the maximum payload size allowed by the > + * transport. "maximum payload size" is ph->hops->get_max_msg_size(ph) ? Should we call this "maximum message size" then? > + * @max_report_sz: Max possible size for the report of a notification message. > + * Set to zero to use the maximum payload size allowed by the > + * transport plus the additional ktime_t timestamp. Same here. -- Cheers, David