From mboxrd@z Thu Jan 1 00:00:00 1970 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.subspace.kernel.org (Postfix) with ESMTPS id 2F8505F878; Sat, 3 Feb 2024 17:19:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706980757; cv=none; b=aN7kdVz0yH1XyCF2ykKMTrxXfifBhwfivXqxRvukwTohuRoRKCwziE356ZP4uxPR2sxMqSiz+dkm6jAn6o00QNpHM6KJ5+Muinbke7UZlQI5eUcsLG67WpEApmprU+IgGbi3JAqGcvJ1fQk48UX/H3g9dcKOf0Vvet/ntjPu074= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706980757; c=relaxed/simple; bh=doXvoR+AfVpZ1PoO5PtzgkHFUyizgc3cYbzXcDFwz2M=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=jBcVUby8fP+2mM1oqV2flKc2qomX5Pt4oLzwLT+PD0kNHLG++PvpF5uNGlwkdOSLIZnNXRog3laPMhmdmUrpJbbFrDrrZfIVr4pqhHEDDeXxX3Ucqg/+LFUwnUPwrm4zLKbrGGbB0rxi7KcPGPwDOfp+YzH+3CuNBWnC4tFzB/g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=GErC5szv; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="GErC5szv" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Sender:Reply-To:Content-ID:Content-Description; bh=p/ZlWZsr1R903M2R0mWOr7CE09pnODUX3Ka/76TZaYs=; b=GErC5szvxzA1JV5e4kYcgNu+S/ G+903hrhR3ZXga1Drgdte0MHZd/mDobB5x5eGMUtmIM6zknQwGmmOn707CGMv9+S+RAAX9H0qolvA EZDGJy/bq5R+jC8zt7JArIIdIyH3cobu+d5wOn6lGaTdRDiJpAzetcQ1KS1md5oVhWf7eu4lLZC2f q6epqGDQH0dC6J5wKRfp3kRtDKmdo7qm4Vk0Cq1KXHZDshE9MtH8ZmvaxVGf1o212D4nFtcatQfHB mebW9bWnTuxwhNcQLDwG1ahEpJaDi8oZoAbWNa7u7OF2EJmkJFrVPImfPMYDBhXZiu/AXy3MFCz+G X1PJxbdg==; Received: from [50.53.50.0] (helo=[192.168.254.15]) by bombadil.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1rWJfZ-0000000GuHc-03he; Sat, 03 Feb 2024 17:19:09 +0000 Message-ID: Date: Sat, 3 Feb 2024 09:19:01 -0800 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] docs: Document possible_cpus parameter Content-Language: en-US To: "Guilherme G. Piccoli" , linux-doc@vger.kernel.org, corbet@lwn.net Cc: linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, kernel@gpiccoli.net, kernel-dev@igalia.com, Changwoo Min References: <20240203152208.1461293-1-gpiccoli@igalia.com> From: Randy Dunlap In-Reply-To: <20240203152208.1461293-1-gpiccoli@igalia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2/3/24 07:21, Guilherme G. Piccoli wrote: > The number of possible CPUs is set be kernel in early boot time through > some discovery mechanisms, like ACPI in x86. We have a parameter both > in x86 and S390 to override that - there are some cases of BIOSes exposing > more possible CPUs than the available ones, so this parameter is a good > testing mechanism, but for some reason wasn't mentioned so far in the > kernel parameters guide - let's fix that. > > Cc: Changwoo Min > Signed-off-by: Guilherme G. Piccoli Reviewed-by: Randy Dunlap Thanks. > --- > Documentation/admin-guide/kernel-parameters.txt | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 31b3a25680d0..e553740190ea 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -4644,6 +4644,11 @@ > may be specified. > Format: ,.... > > + possible_cpus= [SMP,S390,X86] > + Format: > + Set the number of possible CPUs, overriding the > + regular discovery mechanisms (such as ACPI/FW, etc). > + > powersave=off [PPC] This option disables power saving features. > It specifically disables cpuidle and sets the > platform machine description specific power_save -- #Randy