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 B0468259C9C; Tue, 13 Jan 2026 14:07:52 +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=1768313272; cv=none; b=tOghqxxYYqHWoFsZqd6z9OdlUYaLEB6kIA9pygTsdKCAXq/eKOJdzDd/qHwu8jNUBsMdqekyULl/PIkUFlLjKuDtX+Oc8rLvptlQTTBXHdLNjb4gVXziGdVNKDdXjtPYLDvW5LM0okOiNC6u5b5OoqIpD5BgUsNJLkwcuf4oCUQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768313272; c=relaxed/simple; bh=tf7VjSu0IpoV3D/dKKNBxPq01NpdmZ6jhmht6sF3+AA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Rbqn6oDLoNMogXM+bG/R2lK7ytMRhwxqBIJdaGxYycgnKhC9T0JjH4SN5OuzqAmSP1dpLnh/i9jLJpKNiiH0nJspujw/N/i+xyIcu4XlpvHVEj4TBX51dUZrp61hjyJAEFNBaUnk9JB5FhB80bieypBTRJZghxJTP5ysQrdGEVE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=t+T9Y50z; 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="t+T9Y50z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2715C116C6; Tue, 13 Jan 2026 14:07:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768313272; bh=tf7VjSu0IpoV3D/dKKNBxPq01NpdmZ6jhmht6sF3+AA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=t+T9Y50zl5cSQ5yb1OUqCiek/oLQJouQzDWA/FSSDg4UjQcbQpYTVjdit7iguFwli ySksVrIV5YdvqviDpTiZCiizHFxEG/gUBv4pLxasvjvaj27Sx1nc/TbATL0YOkqCTB e085V2Qf2p78J/FC4osBejVRG0j868QtY+cHi015aFm09mM03NPGX704OJWqyXp8Pm 0RMDwddEIMdTgY883Bxm8vwRkTqBcK9z/gp920y4PC5MogExldwfLlHQtUUsR6ATEU uJzo2cUonlv9hd2a6TympZ6CqumW70LxkJw+Voj0PX7HzBIxc4jU7EpxHjwuvYtoAp FbFGwdeTz6dmw== Date: Tue, 13 Jan 2026 16:07:47 +0200 From: Leon Romanovsky To: Konstantin Taranov Cc: Konstantin Taranov , Shiraz Saleem , Long Li , "jgg@ziepe.ca" , "linux-rdma@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [EXTERNAL] Re: [PATCH rdma-next 1/1] RDMA/mana_ib: take CQ type from the device type Message-ID: <20260113140747.GB179508@unreal> References: <1767962250-2118-1-git-send-email-kotaranov@linux.microsoft.com> <20260112075233.GB14378@unreal> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Jan 13, 2026 at 12:27:57PM +0000, Konstantin Taranov wrote: > > > > > > - is_rnic_cq = !!(ucmd.flags & MANA_IB_CREATE_RNIC_CQ); > > > > You need to add code which prohibits future use of this BIT(0) in ucmd.flags > > for backward compatibility and maybe delete MANA_IB_CREATE_RNIC_CQ > > from UAPI too. > > > > Thanks > > > > Hi Leon. I thought that my proposed change is backward and forward compatible. > If I add code that prohibits this flag, then the older rdma-core will fail to create CQ, > as it sets this flag. Add rdma-core should set the flag to support older kernels. > > So, the current solution is as follows: > rdma-core always sends the flag. The kernels without this patch still use this flag. > Newer kernels just ignore the flag and create the CQ according to the client. > It is not fully possible to retire this flag now, as we want to be backwards compatible and > support older kernels and older rdma-core. > Or did you mean something else? Or do I miss something? There needs to be a way to document in the code that this bit is reserved and must not be used. Thanks > > Thanks