From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f47.google.com (mail-wr1-f47.google.com [209.85.221.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B25CB16CD33 for ; Mon, 22 Jul 2024 13:58:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721656727; cv=none; b=lODf0F+DCwu0e9sf4pKqM44h4lGZ4z5+VRu5WuVi+I4mEw01DB6qX0zC+zhhDx6Xeez8vptv0jCwnzmKH8X3vCk0hXZoyg2sWIYra3Wa+pbxcIFE/InUKNPJTRPUi1IEluxBRJlmcVkRvBL36kZtW+lroNAorpah25M1Hw+PPCs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721656727; c=relaxed/simple; bh=8OuEqS9mOLWKFhq5PGx35RUWy1TYEDf2dsaa6U/gv+A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=otmz1Ssm+5uywyWb7AwMgnfcSMDctETMXAlZejBBscQWI7HKsEz2RHq763avQTnCpYI7Nm0p/k7m1KbLqts6b9TUU1yqwQmjEwb+EGll6YWMpyYQREW3lvehcgM4IU43r7uV3aDGXlPTbT/HBJxmWYrVgNKGrP7TdckCRXjVQmM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com; spf=pass smtp.mailfrom=suse.com; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b=ZXij3Uip; arc=none smtp.client-ip=209.85.221.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=suse.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=suse.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=suse.com header.i=@suse.com header.b="ZXij3Uip" Received: by mail-wr1-f47.google.com with SMTP id ffacd0b85a97d-36865a516f1so3053248f8f.0 for ; Mon, 22 Jul 2024 06:58:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1721656724; x=1722261524; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=l5dlFxSv3FmJDU7tjADRKa+8ES8BSMLz55RewmO5kow=; b=ZXij3UipOiBzoogXL3F0IMg8FJKiz6F1p6hzXvH5b6sxGJ1EzbSH47fCWb+hZUj3v7 8ufIQkxNABhFXo5jnTEQ5anu+uAdE28UF0WQRBa+/SbSz5+a/ZP6tsDix9F/NjqWBNM7 ktRxabw+JFTJPDlt4zx04cXt9txgk6HmWPp+g87Jo7bzyCBJP18jzerMWLtI2ekOhprG eWZ+4l9pwgec2AVAOUT8NigHW7k2VyuuVuu0BzfotKayK+DG/JT5MdfTM5glAtfYjzGb hmVau16/TTHxog21xsoRkVSgpgiboXJA4C+dfy+YswtZcDqKlSeS6YPMumfD75x6xOkf QREg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1721656724; x=1722261524; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=l5dlFxSv3FmJDU7tjADRKa+8ES8BSMLz55RewmO5kow=; b=PhU6mQ9jc0vUVPYHgqGlabOQ1iwywQreZNjdNwNVYhEcUagzXER6Yov+5d7iqtulud Bqtk+o/ENDaHatbdTXpu29D0ZlC4BtqjRpj3e3YUylcPk+vB0+O8NfmEX/LhpMJtXyZs KlAsxfHBQr1W0eXIW3ZxukRwYmee8kr4I6vDA26xSaIBhNh+b5QHuVVyZG3h5Auk9tn3 n+2jY1uO09Nwexsg5sw7FWxKm9QGyGcEUVFH7cYHtH5RBuWvuj+BMR3lg81RoiZZeluq Vk5OefRjUIf64nQT3iP2nMEH9gQoSqQPC7CSyLj6nLSn+BytT2lAM7YKOAphnxLWgA3M qtMg== X-Forwarded-Encrypted: i=1; AJvYcCUh+3txRb30hGrr3+tL8yp1zXNQlDoTlM33OCTtBn+Zy8QCX+Nw/3VCcaZppDkgm41SeS+NRBr7KaTJLs1i/1xF2YKXK0YArAXgo5HK X-Gm-Message-State: AOJu0Yx7kY4WpxZXd1TuJV6be7uzU+EGUEQ9F/Rry8mWY1j2A66RvBrt Dgpk69dLwznQOmslGiLKpsSzqKtGf+otH07/6eOJeoki1bfN6QdfSg6BMDVH0TM= X-Google-Smtp-Source: AGHT+IF75AIN+2RIZgOvNN1LxGtFJ+siGH546Ar1hpo7piMbmqYC/NjoJ/ZAr2en/66rK6KOJRpccw== X-Received: by 2002:adf:f303:0:b0:368:3ef7:3929 with SMTP id ffacd0b85a97d-369bae4cfdbmr4886297f8f.22.1721656723976; Mon, 22 Jul 2024 06:58:43 -0700 (PDT) Received: from pathway.suse.cz ([176.114.240.50]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a7a3c8c014esm424599266b.133.2024.07.22.06.58.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 22 Jul 2024 06:58:43 -0700 (PDT) Date: Mon, 22 Jul 2024 15:58:41 +0200 From: Petr Mladek To: John Ogness Cc: Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Juri Lelli Subject: Re: [PATCH printk 1/1] printk: nbcon: do not require migration disabled for nbcon_get_cpu_emergency_nesting() Message-ID: References: <20240719134818.3311665-1-john.ogness@linutronix.de> <20240719134818.3311665-2-john.ogness@linutronix.de> 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=us-ascii Content-Disposition: inline In-Reply-To: <20240719134818.3311665-2-john.ogness@linutronix.de> On Fri 2024-07-19 15:54:18, John Ogness wrote: > Since entering emergency state disables preemption, there is no > need for nbcon_get_cpu_emergency_nesting() to explicitly require > migration disasbled. Either the current CPU is in emergency state > (and thus preemption is disabled and the nesting level is not > zero) or the current CPU is not in emergency state and the nesting > level must by definition be zero, even when migration is enabled > and the current CPU could change. The current CPU could never > change to a CPU that is in emergency state. > > Reported-by: Juri Lelli > Closes: https://lore.kernel.org/aqkcpca4vgadxc3yzcu74xwq3grslj5m43f3eb5fcs23yo2gy4@gcsnqcts5tos > Fixes: 46a1379208b7 ("printk: nbcon: Implement emergency sections") > Signed-off-by: John Ogness Reviewed-by: Petr Mladek Best Regards, Petr