From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f43.google.com (mail-ej1-f43.google.com [209.85.218.43]) (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 04CCB186E4F for ; Wed, 31 Jul 2024 14:59:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.218.43 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722437953; cv=none; b=uyCFEFfM63+RjoOowULMC3hZxt1M2lTehnVd/cWGMpRwsTEginUjHfyhjZwswP+COewoUvDuEQi2kHBLD96AJ4o+T2P10SzAtIhwUpVOf4WOIRF39L0YnanIBKpQaLeSAqA3Da17dD8OztnFycNdGw8jPYQTZoU/uUtbWvLcQcQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722437953; c=relaxed/simple; bh=mv6la1zzKuIOdZkN18IqBhuFvq9G6xkdwAPiC81eQzk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=qbbgJ4c6N7J63/h1T7+3UYPJPku+UlQrOxNJALn64Otxl+txvKDm/YxK2YZ+tuztu5r0fwIHiIcqoWfI80oT9jRyaoo8iaiye6oy8WS9QfT06rqKYSToGROoPHGXmx2Sn38Qm1zsWwN6Nx6/xWhW7S7AoDlauFS7gl5C1cXl6z8= 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=WK16iXdq; arc=none smtp.client-ip=209.85.218.43 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="WK16iXdq" Received: by mail-ej1-f43.google.com with SMTP id a640c23a62f3a-a7aada2358fso183333966b.0 for ; Wed, 31 Jul 2024 07:59:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=google; t=1722437949; x=1723042749; 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=jhbI2qcUD6BnGrdQ3FwKQWVw6U417wDQ0L9tf2bpCDU=; b=WK16iXdqt2zQPwMABVBpZOf3PLWi6HIAfMgAgeAcyzbu32rNRaaMCur8qoE9YNLlVj nbM8QVGY7ziL42YMPkZTCDquuKrhwntqB0YI2id0rLZ3RS41j5IOLJRC+rnE8cT6YI1P kXLFkoOfiTdjgjDe1GBwJ9QjmdpQJqwZ1HB6BkQvs9zkQHNzii7Wg5YZVuLf7hDSPu6c GbmaFACwT7dapHYTeltz/RuNy+aUbJB9JWmqrNsTcyEcrETKxu8m+sY5D/LovoWZueGV 6TXHTbIJd14kEmXVAPVmFIqEYBZlpx5GAicpx0bAChF1qGTQ/wQbFdPbYPMRM5rnk5cK 0ydg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1722437949; x=1723042749; 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=jhbI2qcUD6BnGrdQ3FwKQWVw6U417wDQ0L9tf2bpCDU=; b=sx8Mj2fDxBSiwMJg95ll1JKolfYVdPAtxCm38DTkWHYGKmZ3uQFfByk/ZpL995o3cX c4G0Qq17tuxfMWsIKEMkNMiAkKqxAkcVNHd3iLMxX0utZMVRQNioxcUBLcFi/OUZcUEe C4ggd89n/aPGFSyq8Vi30rtu6XHO8DxVeonv4ntne+GadpeoBgldkMkRN9HqddEG4Zao ZlWejOzK2GNoGL11Cqo/Ka5yXISazpSAQqmpviqd+/Nwfy7eajl1uJCdkDRj11js2aoX OizpSQJN/YxnM08Dl2EhRi13wQBY4OG5ugRm5UH/JEl+aiAt8iMoGHx7sytJdKt8LFFg XKaw== X-Forwarded-Encrypted: i=1; AJvYcCVDrS3RnYB69WQ6ianu0o26o+TOS5tGZ+TFeF6rz7T4/ZVWmINysavt9YfUMvMzUaqpnEaWi3HBXo5NZ3RoXD1sPsjG6PQoprQWUjkW X-Gm-Message-State: AOJu0Yyf6ONHgQyfyifnFpF0L8kXtQ2IworRSu9fSIuwafzWDVVeRRzS Zs+bIswKtDEKo6p4sJh1bSre3uT17p476Lq1CCYznA2JkHzfD+S2Qp749sLxfDY= X-Google-Smtp-Source: AGHT+IHVH+Xx7HrL913MR5RlHCHu1xgZx5vzcNo97br513mbozSHlnxNxBR8fViKxEHdoxWFvBT45Q== X-Received: by 2002:a17:907:2d86:b0:a7a:a33e:47bf with SMTP id a640c23a62f3a-a7d859576eamr576235566b.18.1722437949297; Wed, 31 Jul 2024 07:59:09 -0700 (PDT) Received: from pathway.suse.cz ([176.114.240.50]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a7acada27ddsm771813366b.184.2024.07.31.07.59.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 31 Jul 2024 07:59:09 -0700 (PDT) Date: Wed, 31 Jul 2024 16:59:07 +0200 From: Petr Mladek To: John Ogness Cc: Sergey Senozhatsky , Steven Rostedt , Thomas Gleixner , linux-kernel@vger.kernel.org, Greg Kroah-Hartman Subject: Re: [PATCH printk v3 13/19] printk: nbcon: Show replay message on takeover Message-ID: References: <20240722171939.3349410-1-john.ogness@linutronix.de> <20240722171939.3349410-14-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: <20240722171939.3349410-14-john.ogness@linutronix.de> On Mon 2024-07-22 19:25:33, John Ogness wrote: > An emergency or panic context can takeover console ownership > while the current owner was printing a printk message. The > atomic printer will re-print the message that the previous > owner was printing. However, this can look confusing to the > user and may even seem as though a message was lost. > > [3430014.1 > [3430014.181123] usb 1-2: Product: USB Audio > > Add a new field @nbcon_prev_seq to struct console to track > the sequence number to print that was assigned to the previous > console owner. If this matches the sequence number to print > that the current owner is assigned, then a takeover must have > occurred. In this case, print an additional message to inform > the user that the previous message is being printed again. > > [3430014.1 > ** replaying previous printk message ** > [3430014.181123] usb 1-2: Product: USB Audio > > Signed-off-by: John Ogness Reviewed-by: Petr Mladek Best Regards, Petr