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 DC6BA56B6B; Thu, 25 Jan 2024 13:35:26 +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=1706189728; cv=none; b=obfSBng0cOwdtozF4BHiYL/bLaOYR8T+BbdbR6p5VbL97FrYt4rvmd3W2ip1UmMOjGIRDOu9p2emE6UN9mDgP0obgwTl8Pyh4SOAiQwKAWAQxTgiwOZUhdAXk9xs1Wo3hRDOGfjmEa1cNiQ5StZwkd4RYyPJC1vP4YcCIj7zfMk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706189728; c=relaxed/simple; bh=fvn+bMBhFq4DGQCYdmmItxFzpZ4dLpUiVSBLUvy+Xqw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Si0y0WkVvixUTCpvq3bV0NXZiwcSZkRbDQm4vGIr/BzOaDFk0Mqbs9ywGWPAnXuV6E8ywJKBV31WeO4afKQvqP/P9RuQdK69V6jyVUA77WPzdQs10AA38xlZwwx0xfYPqeHXguvnKpRm/KwJ9W+nId8y+2x5g+oy92OMieWevBY= 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=EveXoCaV; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=PQTGwAQR; 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="EveXoCaV"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="PQTGwAQR" Date: Thu, 25 Jan 2024 14:35:23 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1706189725; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=F9UO/TwyZdEj3iKgu2t8LOSQIGAMLuKX9wZHWL1TwD8=; b=EveXoCaVPjB1/4K0mdWTh9NDiOdMTJleMucr6NgKSgbgC2399afEmy+ZEW40cCnhH51PdY +QE+IsM91122AOyYOCtk8MYz6t+X5nfg7ILPP4DZkQquAWR1my5xaEvi0Vczkp+9eaq/4m RKvfSoiff/CV/OSvBA+e4L4u+Q1sSIw7aaKapdsDiJ2287lOr2vtYF6WFtjnpF4XlmT/ZN tbJle9lLFLfrDv3lj9KFHg+yQZDxYbchvOArQaZj3rdqULeNVQhBVHf79cRhcnMQzFsHVl VGw4caYJZhzO9KJeMLVYzFzYxnFpba0JZY/Jo7kA0kVgeK4kfFEvsZtO2+SgXA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1706189725; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=F9UO/TwyZdEj3iKgu2t8LOSQIGAMLuKX9wZHWL1TwD8=; b=PQTGwAQRZ+rmvGxCERiEX0EX037zJJjnB0weA+PXdhNzvdUHYsjjwae7uRf0zZ5h4Izbkj ucUMPr/Mi82ZpMCg== From: Sebastian Andrzej Siewior To: "Chang, Junxiao" Cc: John Ogness , "tglx@linutronix.de" , "rostedt@goodmis.org" , "linux-kernel@vger.kernel.org" , "Li, Hao3" , "Li, Lili" , "Gao, Jianfeng" , "linux-rt-users@vger.kernel.org" Subject: Re: RE: [PATCH 1/2] printk: nbcon: move locked_port flag to struct uart_port Message-ID: <20240125133523.W7aDeBqt@linutronix.de> References: <20240123054033.183114-1-junxiao.chang@intel.com> <20240123054033.183114-2-junxiao.chang@intel.com> <87le8f9i75.fsf@jogness.linutronix.de> <20240124100524.ZyAPfPU5@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=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: On 2024-01-25 01:08:24 [+0000], Chang, Junxiao wrote: >=20 > Issue could be reproduced with our hardware every time. My cmdline is: > BOOT_IMAGE=3D(hd0,gpt2)/boot/bzImage-linux-intel-iot-lts-rt-6.6-kernel > root=3DPARTLABEL=3Dprimary rootwait console=3DttyS0,115200 console=3Dtty0 > init=3D/sbin/preinit-env console=3DttyS4,115200n8 console=3DttyS5,115200n8 >=20 > If you would like to try any debug patch with my ADL hardware, please fee= l free to let me know. >=20 > For console pointer sharing issue, from code logic point of view, the cal= l chain looks like: > serial8250_register_8250_port -> uart_add_one_port -> serial_ctrl_registe= r_port -> serial_core_register_port -> serial_core_add_one_port >=20 > In API serial_core_add_one_port, uart_port's console pointer is assigned = with driver's console pointer: > uport->cons =3D drv->cons; > Driver's console pointer points to static structure "univ8250_console" wh= ich is defined in 8250_core.c >=20 > That is, all 8250 serial devices' console pointer are same, they point to= univ8250_console. Okay, So that I see this and the unbalanced acquire/ release part with the attached patch. I leave it to John=E2=80=A6 Btw. You don't see kernel log output on ttyS4 + ttyS5, right? Just a login prompt. =E2=80=A6 > Thanks, > Junxiao Sebastian