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 B360F1B95D for ; Fri, 16 Feb 2024 09:23:06 +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=1708075388; cv=none; b=ra+NuklocwXWT1Fn/d9ASKrLNscIYUganAdzfyqacBMLQHKotDHjwzlgDVh4MSRQ4x5PlI5MS5ftCR90/sS/3hyQ+0tfbIK0NNQWdZx4Aob5O8E91sfRCOr8ocNL7eZuaYsilPuvpDYu+XaZ/SuVVZ/D+P1mvh4G6fk+U43tExE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708075388; c=relaxed/simple; bh=svr/tG93+IhRjX3JlqAVKVH56EQboOnBEuSSo7Dfcac=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=pV2xLHOK+YNulNncCbZirYyesbE05XzKzsTB2uI4u1H4fthc1WVcQ8JaN7N8XlB1Aw7QUy1/WqqCUsZjYVNnWdGSxDCTwUsqNu1Mo8XejyWTg6Vd/ySYHnvWaWjy93t9jMB/zMXHECU+Yjcw4XsYKBFT8g430Zk4B7Rs0RaMQ48= 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=qFpPyopj; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=vqSY7Xwh; 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="qFpPyopj"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="vqSY7Xwh" From: John Ogness DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1708075384; 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: in-reply-to:in-reply-to:references:references; bh=svr/tG93+IhRjX3JlqAVKVH56EQboOnBEuSSo7Dfcac=; b=qFpPyopjiaOKr9Bf6XrK720PVB0dMLOvho+du5tVdDUZ1qft8YwkL2JwBORKgnoIyWW3o2 Rvlb2Sp0E0ZOGGNC+mixsuXB+778n4WSo6fBbM1gVrY/0g+igWlzArLL9aI8Yc+Im8WOec M5eLGOCTrAghca1mLE+6KufInx1CIMKCdZgYY68Jwm5lxEwl3lcPVAl8E+BO+8lRG1TgYW 2Daj/cao8YTgxXvemqeNIA3xvPmQgJdl22C3VzBz+SdlYGsZO6+i+/IL80Ce+Hv5uqUjGN LAjl2OXjO6vwqN0hjk/wujaSPIrMrjTX4rzT+cw4jCLGlS7KZwyfxtH5Vxoi7Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1708075384; 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: in-reply-to:in-reply-to:references:references; bh=svr/tG93+IhRjX3JlqAVKVH56EQboOnBEuSSo7Dfcac=; b=vqSY7XwhX8Xmi7zOWwE/1fj3g2KxcOJjLlJBPIBw+ZsZmUWyVuLvRwLYPf9CAexm7fQzTK Zn6X36wlEpDSw5BQ== To: Stephen Brennan , linux-kernel@vger.kernel.org Cc: Petr Mladek , Steven Rostedt , Sergey Senozhatsky , Stephen Brennan Subject: Re: [PATCH] printk: save loglevel before console_verbose() In-Reply-To: <20240216005128.1045812-1-stephen.s.brennan@oracle.com> References: <20240216005128.1045812-1-stephen.s.brennan@oracle.com> Date: Fri, 16 Feb 2024 10:28:46 +0106 Message-ID: <87eddcsqzd.fsf@jogness.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 On 2024-02-15, Stephen Brennan wrote: > In panic() cases, console_verbose() is called, clobbering the > console_loglevel value. If the bug which led to the panic related to > printk, it can be useful to know the log level prior to the > console_verbose() call. I've done a *lot* of printk debugging over the past 6 years and have never had a case where this would be useful (or even interesting). I assume there is some rare and particular scenario you are trying to debug. And once you've debugged it, it is no longer useful for you either. IMHO this does not warrant adding an extra global variable for all Linux users. When Petr gets back from vacation, maybe he will have a different opinion. John Ogness