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 37F933A0B1C; Tue, 24 Feb 2026 14:47:59 +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=1771944479; cv=none; b=K1Gy3tHTMkLIt/H1y9iuxK/aF4cJ8NHoDvzLaXZSly47M1mgQILrk/mxCJfpkgzrebOBszOTN9MzZ51KbXMYyCib6ZHUePnDIjJOcC0rfogC9tErffacmHc12Zhc4jFVOfyBj7uNSsedycrXUyuKUknFBxqr8o/C/Nuc5SzOV+0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771944479; c=relaxed/simple; bh=VISfPsroj9CqNNLmyknkEDkN8jYvZkbvfaoN8GJsuxU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=piFu3QWDlpHU/sw2GajyUa5vo0K4G61j3CWRqcy9Z6RsOKw5lrhFD/xhsugglchmGuqHpl32DcxJOZxapPoceSR6H7krM3zebJW/rDW9pnkRnh47nDmsfACY0iM2ZunTmGqOiUhbWbjw6VQz3xd39C2NuBN2Un4R/RIBl0DZGKA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=M0dt8YRY; 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="M0dt8YRY" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EE78AC116D0; Tue, 24 Feb 2026 14:47:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771944479; bh=VISfPsroj9CqNNLmyknkEDkN8jYvZkbvfaoN8GJsuxU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=M0dt8YRYHPrbnyx3uhNU19gYdoqIoN/XiGW9H++Fve4PwXRaVW1kicA+bbsQgO1Yn BipsDgTygHnHxeakOINj61sk590zY2UuVzR2SN6pKqUBPEejasvWa7A2twGhQvgfz8 wqcvMYM0id8wlUkog7xotIYANaFXJ5EwSKXczuEkyOdjgMokKdQmAKdC4r59OiwjND LEGWxGa7CQ7aH5iyZUvzaIzIS1x0NhM4UJyRR/suZL7qqz4TgPJvPOoKGYJ4ryYcer G4oiaF0G3LjdaguBSh0jluKNojlGfp/umEFk7Ju2LbzXnIyz8oqk/JKLcS5wvUW23B oEVfcTipjQLnQ== Message-ID: Date: Tue, 24 Feb 2026 15:47:53 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v5 01/38] gpu: nova-core: fix aux device registration for multi-GPU systems To: John Hubbard Cc: Alexandre Courbot , Joel Fernandes , Timur Tabi , Alistair Popple , Eliot Courtney , Zhi Wang , David Airlie , Simona Vetter , Bjorn Helgaas , Miguel Ojeda , Alex Gaynor , Boqun Feng , Gary Guo , =?UTF-8?Q?Bj=C3=B6rn_Roy_Baron?= , Benno Lossin , Andreas Hindborg , Alice Ryhl , Trevor Gross , nouveau@lists.freedesktop.org, rust-for-linux@vger.kernel.org, LKML References: <20260221020952.412352-1-jhubbard@nvidia.com> <20260221020952.412352-2-jhubbard@nvidia.com> From: Danilo Krummrich Content-Language: en-US In-Reply-To: <20260221020952.412352-2-jhubbard@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/21/26 3:09 AM, John Hubbard wrote: > The auxiliary device registration was using a hardcoded ID of 0, which > caused probe() to fail on multi-GPU systems with: > > sysfs: cannot create duplicate filename '/bus/auxiliary/devices/NovaCore.nova-drm.0' > > Fix this by using an atomic counter to generate unique IDs for each > GPU's aux device registration. The TODO item to eventually use XArray > for recycling aux device IDs is retained, but for now, this works very > nicely. > > This has the side effect of making debugfs[1] work on multi-GPU systems. > > [1] https://lore.kernel.org/20260203224757.871729-1-ttabi@nvidia.com > > Reviewed-by: Gary Guo > Signed-off-by: John Hubbard Applied to drm-rust-next, thanks! [ Use LKMM atomics; inline and slightly reword TODO comment. - Danilo ]