From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (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 783D23BBF0 for ; Sat, 22 Jun 2024 21:21:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719091295; cv=none; b=Hv8QlEOUs7qfOlkWyRZyvTSR1Ghi1tIdoiL9wr160QJeSsoSTRS5/OFihieke0T8ObRWCxo8LRCFGQXrr2yNkjNyKFOWkstVgwiAgB/BCqSex1+kfqV0yjyS6ofqT7KSKmHDJINmyYpQ2I0oW/MSTyjFQGyhdrFGZJwISJSb8ys= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1719091295; c=relaxed/simple; bh=EHxmzrUN/A73frTQagvw4dP1WhU1NGaVPpCc4+gsYAc=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Y+QYJVKqRwRwxLnNFrs5/ZXzVqWtjRLCidQpjn/pwVeCEliIbJh/fAUSCs9DwZy8l6She86ZOpfP7MVGmasuIZDZv/QMpHXvq7sBLGj1k4Od/jdGiWrx4tOi5PdPJfKCRDs9i+7nLgz0YVNQVtfMcDtn3HEv62iEJNJIpObrOt4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=lhAnRcmv; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=RUI416Xc; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="lhAnRcmv"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="RUI416Xc" From: Thomas Gleixner DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1719091285; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cK0peedHHtHTedjCU+iox2hw8klvuHZB6LWN/BOo6NU=; b=lhAnRcmv8notJ4xn6XR3VIWyHV9sQoGQM+W4ULQS/TT8wepwj5+3In7dqeMCVuzUwck3BZ L5WopjkXETHpnExz/ruyiA38x+/4rI5TKL1L5eODmcSrlnWAMFNbnHax3xxTJHvvfUoA/J MfzV9vF6vQeb19lHlWYkh2XBZMolNL1z2R7PL4Z90pv/mEsQYxeCYqM4zNJyadb3nGSoHz eaOwWWqF2p/e7AjS8Gs++ldxJ5fY5qLvVlj1F+br/eVfoRbXiwC4Aqil0KM+lyBOEJwjnh xNGXRwHdeyRw89j3z6XIrmJmXUknX8maXTsnZmEry0aUTIf2PvrdAoCcxZh90Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1719091285; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cK0peedHHtHTedjCU+iox2hw8klvuHZB6LWN/BOo6NU=; b=RUI416Xc28PiIL5XhT9HWKSfnKhzo7/u7Xcd/mJnq/y+6JuV1pWUmDhaNBJo4IlqSzvgMG +RbBYA1VXQbSzMAg== To: Huacai Chen Cc: Huacai Chen , loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, Xuefeng Li , Jiaxun Yang Subject: Re: [PATCH V2] irqchip/loongson-eiointc: Use early_cpu_to_node() instead of cpu_to_node() In-Reply-To: References: <20240620020625.3851354-1-chenhuacai@loongson.cn> <87msnem3i1.ffs@tglx> <87pls9z3g0.ffs@tglx> Date: Sat, 22 Jun 2024 23:21:25 +0200 Message-ID: <87jzigznai.ffs@tglx> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Huacai! On Sat, Jun 22 2024 at 19:23, Huacai Chen wrote: > On Sat, Jun 22, 2024 at 6:17=E2=80=AFPM Thomas Gleixner wrote: >> That does not make sense because it's exactly the same situation when >> you compile a kernel with NR_CPU=3D8 and boot it on a system with 16 >> CPUs. Then early_cpu_to_node() does not give you anything either. >> >> So what's the technical problem you are trying to solve? > > Frankly, there are some drawbacks on our hardware. On a dual-bridge > machine, there are two eiointc instances. Even if nr_cpus limits the > "possible" CPUs, we still hope the eiointc driver can initialize > correctly, otherwise the machine cannot boot. Hope does not help with technical limitations :) So if CONFIG_NR_CPUS is not big enough to map the second node, then the machine can't boot. If nr_cpus limits it then early_cpu_to_node() because that mapping is only limited by CONFIG_NR_CPUS. Right? If so, then please explain all of this properly in the change log. Thanks, tglx