From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from canpmsgout01.his.huawei.com (canpmsgout01.his.huawei.com [113.46.200.216]) (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 386363128CA; Fri, 17 Apr 2026 03:22:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=113.46.200.216 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776396134; cv=none; b=To+bq6xrxushf5XjrjmPfj3ykbvNgJuYwBEKcjTmAKx93mAtUYRHv2+nuAlUn5R/rNe4BM/rM9GZjkahuLqW555WiMrKpECFb7n6lNENuFprMvIcXZDBz4M748Mw/4mpl3AmZJ8hLwviggsquxoERPk5QZw/MSVvpazAc8r59VQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776396134; c=relaxed/simple; bh=86K7XkxC/v2L5UoF5U0XaLF4l4XC/tIPLraYXXMY20w=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=elNHy4cnXKJwIo3OnmAD/ZMZ7BrBMWFVFNU5M/MRPtaf845Dv8/5kz2TG9pfRI4YyJUGbZskBCQD8fyvTozOQvxW6AM8E4nZ0MOq7Isw75CG0NhjHd6eo9cVZTHx2B9hoLg5PzRE6lUzOcS8Io0hCV/NlSxv2UlmD3jm8C+NFs0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b=6EOdu9ab; arc=none smtp.client-ip=113.46.200.216 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=huawei.com header.i=@huawei.com header.b="6EOdu9ab" dkim-signature: v=1; a=rsa-sha256; d=huawei.com; s=dkim; c=relaxed/relaxed; q=dns/txt; h=From; bh=SOq/ZxC6M8wVXHNjMQe7Rw4xaPWmBQS6yZbztjmE8kw=; b=6EOdu9absDQrLD3VgjMBEJCMhp8NEszwwLk5P7IzqAGIPcDk3ND55TevuhT8VJZGzBGK1JCLT /jO7I+8XocXiZgiD8T2G4pFXNQlJ0LtP7tFzeUv3Hxz62EOwYcn0zQpV+5uZGwmNpYYs3lwRRyi 2vVv0Ix4vAbCoeeUwDBjwE0= Received: from mail.maildlp.com (unknown [172.19.162.197]) by canpmsgout01.his.huawei.com (SkyGuard) with ESMTPS id 4fxg4z3fH5z1T4Gh; Fri, 17 Apr 2026 11:16:03 +0800 (CST) Received: from dggpemf500011.china.huawei.com (unknown [7.185.36.131]) by mail.maildlp.com (Postfix) with ESMTPS id 9AFF940576; Fri, 17 Apr 2026 11:22:06 +0800 (CST) Received: from huawei.com (10.90.53.73) by dggpemf500011.china.huawei.com (7.185.36.131) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 17 Apr 2026 11:22:05 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , CC: Subject: [PATCH] docs: Update nosmt support for arm64 Date: Fri, 17 Apr 2026 11:25:40 +0800 Message-ID: <20260417032540.3720627-1-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain X-ClientProxiedBy: kwepems100001.china.huawei.com (7.221.188.238) To dggpemf500011.china.huawei.com (7.185.36.131) commit eed4583bcf9a6 ("arm64: Kconfig: Enable HOTPLUG_SMT") enable HOTPLUG_SMT for SMT control for arm64, but the documentation was not updated accordingly to reflect that ARM64 now supports control SMT via boot parameter and sysfs knobs: 1. Boot parameters: nosmt: Disable SMT, can be enabled via sysfs knobs. nosmt=force: Disable SMT, cannot be enabled via sysfs knobs. 2. Runtime sysfs controls: Write "on", "off", "forceoff" or the number of SMT threads (1, 2, ...) to /sys/devices/system/cpu/smt/control. Signed-off-by: Jinjie Ruan --- Documentation/admin-guide/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index cb850e5290c2..6a73eb5abae9 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4661,7 +4661,7 @@ Kernel parameters nosmt [KNL,MIPS,PPC,EARLY] Disable symmetric multithreading (SMT). Equivalent to smt=1. - [KNL,LOONGARCH,X86,PPC,S390] Disable symmetric multithreading (SMT). + [KNL,LOONGARCH,X86,ARM64,PPC,S390] Disable symmetric multithreading (SMT). nosmt=force: Force disable SMT, cannot be undone via the sysfs control file. -- 2.34.1