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Date: Wed, 9 Sep 2026 12:18:31 +0100
From: Cristian Marussi <cristian.marussi@arm.com>
To: rolanddreier@rivian.com
Cc: Sudeep Holla <sudeep.holla@kernel.org>,
	Cristian Marussi <cristian.marussi@arm.com>,
	arm-scmi@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] firmware: arm_scmi: Protect xfer->async_done with
 xfer->lock
Message-ID: <aqE7-6gwOmh8Sr4o@pluto>
References: <20260909-scmi-async-done-race-v2-0-cc5dec25c6be@rivian.com>
 <20260909-scmi-async-done-race-v2-1-cc5dec25c6be@rivian.com>
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In-Reply-To: <20260909-scmi-async-done-race-v2-1-cc5dec25c6be@rivian.com>

On Wed, Sep 09, 2026 at 04:32:27AM +0000, Roland Dreier via B4 Relay wrote:
> From: Roland Dreier <rolanddreier@rivian.com>
> 
> Asynchronous SCMI commands are completed by a delayed response. The RX
> path signals the response with complete(xfer->async_done). Unlike
> xfer->done, xfer->async_done is a pointer to a completion owned by
> whoever is waiting for the delayed response, and it stays valid only for
> as long as that waiter is still waiting.  In do_xfer_with_response() it
> is a DECLARE_COMPLETION_ONSTACK() in the caller's stack frame.
> 

Hi,

LGTM.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>

Thanks,
Cristian