From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) (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 8BE451843; Thu, 21 Dec 2023 02:21:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=flygoat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flygoat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=flygoat.com header.i=@flygoat.com header.b="eBwbc/vS"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="9b+5WMMO" Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.nyi.internal (Postfix) with ESMTP id A2DC55C02BB; Wed, 20 Dec 2023 21:21:46 -0500 (EST) Received: from imap44 ([10.202.2.94]) by compute3.internal (MEProxy); Wed, 20 Dec 2023 21:21:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=flygoat.com; h= cc:cc:content-transfer-encoding:content-type:content-type:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to; s=fm3; t=1703125306; x=1703211706; bh=u4Mi26pZJKyRO9fetP7V1s8Zt2g/ERIujlW54YGgiXg=; b= eBwbc/vSeN+oifqqPfn4rQ/wC99kqiy8XKqgN9vcENnhpxuZ8mnCTDfv6tmg1C1h W2Nh7VL9JRYhls71S8OhCWLnNJ++aGMBEUjotmCXGdb5aqkeRtYcp9QRN2z5lbSf rvEPMkfELnbPokg7TndubGCSNpeX29e9WnA4b6rG6+xKBDtPzz1teZq5JHn7Lpii PU0Apxl8D2oifv4LqwVOW5+urQxuCi8xhvYW935HXzXypsC7iOzAho0T02PSgk02 kNE1Q6NTLzsaapCb1ftPAEc8/T+B3RqVuln7QpS0Gei1SKgbclBLGFvRhJrO0gsw 93Mt5Uy6HeZGcSI3exjUIQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:content-type:date:date:feedback-id:feedback-id :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to:x-me-proxy:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm2; t=1703125306; x= 1703211706; bh=u4Mi26pZJKyRO9fetP7V1s8Zt2g/ERIujlW54YGgiXg=; b=9 b+5WMMODPhB1eHvwmjFnIAKgsdqhCJoNNOMCKPcjBrCAxSwg8RAWkgs0O/zuGKtQ qDWqoc7fNqNuDxSnO+FDUaJpp1Nv/0OyYd0UVcgw4GJiFZSfDxhxJ1jdZmAD4PUU pILlpUJDDwb55rFNLJO9ZEMEY90qXqUevrgVzBV6KoQPe1HJ/R/Zy8gVXlBeGzsR NhWE22gslYkkzPTIgXTqiaJIL7m/djwFZHWFKLdm+7kQCrwCznWJF4LK59ch+JNW SiO50nvhFXU0osca0XuXBZcMpn5bHlgybkeRTugL8et5XhZ5veHY76xxLucQZ2Hd RwiumlKRu9NKuPPIzSsqw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvkedrvddufedggeeiucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne cujfgurhepofgfggfkjghffffhvfevufgtgfesthhqredtreerjeenucfhrhhomhepfdfl ihgrgihunhcujggrnhhgfdcuoehjihgrgihunhdrhigrnhhgsehflhihghhorghtrdgtoh hmqeenucggtffrrghtthgvrhhnpeeihfdukeelvdduiedtieetieekvdegjefhteelhfdv veelvddvffeflefglefhueenucffohhmrghinhepgihktggurdgtohhmnecuvehluhhsth gvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomhepjhhirgiguhhnrdihrghn ghesfhhlhihgohgrthdrtghomh X-ME-Proxy: Feedback-ID: ifd894703:Fastmail Received: by mailuser.nyi.internal (Postfix, from userid 501) id 5C2BD36A0076; Wed, 20 Dec 2023 21:21:46 -0500 (EST) X-Mailer: MessagingEngine.com Webmail Interface User-Agent: Cyrus-JMAP/3.9.0-alpha0-1364-ga51d5fd3b7-fm-20231219.001-ga51d5fd3 Precedence: bulk X-Mailing-List: linux-mips@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <96543d4c-f08e-443d-9a85-9257fc4f4b6c@app.fastmail.com> In-Reply-To: References: <20231029-mips_debug_ll-v1-0-d7a491e8c278@flygoat.com> Date: Thu, 21 Dec 2023 02:21:26 +0000 From: "Jiaxun Yang" To: "Thomas Bogendoerfer" Cc: "linux-mips@vger.kernel.org" , linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/8] MIPS: Unify low-level debugging functionalities Content-Type: text/plain;charset=utf-8 Content-Transfer-Encoding: quoted-printable =E5=9C=A82023=E5=B9=B412=E6=9C=8820=E6=97=A5=E5=8D=81=E4=BA=8C=E6=9C=88 = =E4=B8=8B=E5=8D=889:18=EF=BC=8CThomas Bogendoerfer=E5=86=99=E9=81=93=EF=BC=9A > On Sun, Oct 29, 2023 at 02:53:01AM +0000, Jiaxun Yang wrote: >> The plan is to elimiate platform specific early_printk and >> cps-vec-ns16550 by debug_ll and earlycon. > > https://xkcd.com/927/ ? > > sorry I don't think that just another new function is good approach. > Doing this will end up with another method for early debugging and > all other will stay. To summarize how are we going to handle low-level debugging after this s= eries: 1. You are lucky enough that the problem happens after console system in= itialized and you have stack working: go earlycon, or on very few old platforms= with platform early_printk 2. You are debugging zboot: debug_ll 3. You are debugging SMP bootstrap code like cps-vec: debug_ll 4. Your kernel crashed at the middle of no where before trap_init: debug= _ll Thanks > > Thomas. > > --=20 > Crap can work. Given enough thrust pigs will fly, but it's not necessa= rily a > good idea. [ RFC1925, 2= .3 ] --=20 - Jiaxun