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 5DA5923E25C for ; Mon, 10 Feb 2025 15:39:07 +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=1739201949; cv=none; b=t4g8IutfmHiof6fqPtjM8LX3VImRWKCpWrjkh8pWDVUNdutieGnJSYpWuw1OzelZBr57PynvIRt8gKBJCpsdTWLXv6JnqkEWKBE0CuArHqGAIco9AYJDXP8I0K6mLWiKeK/SDm1pZxKURLXCUEYmrxK7POGtXsaXkeUyEYagP2o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739201949; c=relaxed/simple; bh=bhIHagS9meSabUPfTGuF7xlaMWOXvPmjoZ4/jfSEJsI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GTW46702Y3t+rOEOOILPN0cIAa/arqlj4Wz+5ripMF/9bxplkY+oC6FLWFZFaDNZzwFtIW2Bm+KFh7283NGvnhdDwiWyN2wB63L8f72RbasttXGUA10Hms3mWOCa+smk/r8aJfVGvGilRpee+eknCvYVWJxyBDQEghlbswv00B0= 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=qPV+niyt; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=JC0Ek3bS; 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="qPV+niyt"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="JC0Ek3bS" Date: Mon, 10 Feb 2025 16:39:02 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1739201945; 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=FVUBiaoeWeksMfqaUXNGg5STI1bae+8Yqz5cnicePdE=; b=qPV+niytIhYOhSM7bRzAb3GXPXTNY9jj6pj718SCdZX+U5XVSAcgRr1JLZodYs/9TFUSQt jTYU6SV2RiLnrzyV2jZDlWgwA+0bquQFo03QwdnTXBDhwoYoe980wGtHj4QxOr06RT4DSt 8ddXsI2fpEn0ubX+eaF5UTWuqud2TYsdIroRau2Wndbgs7his95TPoNyABloBlr/7Xw/8B bDKfEPenzMJSWoeKq9+icGVHgTD7Rkxg33pUjFZJJ/YkgFjPMFLrW73YmrnhMNCOtBBhkp QAgElWCt1siSQL7Evu4w9YM3as5CrBCeEYAFvv9c01I61W2gqIxxSA/IPmg7IQ== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1739201945; 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=FVUBiaoeWeksMfqaUXNGg5STI1bae+8Yqz5cnicePdE=; b=JC0Ek3bSh7t7IktBNjUPgmVDll0jqwdgwkJ2nqdgT6WYgw2HTZbpzp2lOtqAK28AbE3d/0 9HFPIP14YS4FHwAQ== From: Sebastian Andrzej Siewior To: "Russell King (Oracle)" Cc: linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, Ben Segall , Catalin Marinas , Dietmar Eggemann , Ingo Molnar , Juri Lelli , Mel Gorman , Peter Zijlstra , Shrikanth Hegde , Steven Rostedt , Thomas Gleixner , Valentin Schneider , Vincent Guittot , Will Deacon , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v2 3/9] arm: Rely on generic printing of preemption model. Message-ID: <20250210153902.06VTSS6d@linutronix.de> References: <20250203141632.440554-1-bigeasy@linutronix.de> <20250203141632.440554-4-bigeasy@linutronix.de> <20250210120429.iFfBClW1@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 In-Reply-To: On 2025-02-10 15:16:11 [+0000], Russell King (Oracle) wrote: > On Mon, Feb 10, 2025 at 01:04:29PM +0100, Sebastian Andrzej Siewior wrote: > > On 2025-02-03 15:16:26 [+0100], To linux-kernel@vger.kernel.org wrote: > > > __die() invokes later __show_regs() -> show_regs_print_info() which > > > prints the current preemption model. > > > Remove it from the initial line. > > > > > > Cc: Russell King > > > Cc: linux-arm-kernel@lists.infradead.org > > > Signed-off-by: Sebastian Andrzej Siewior > > > > Is it okay, to route this via the sched tree? > > Sorry, its not obvious where show_regs_print_info() prints this. > dump_stack_print_info() itself doesn't directly. print_worker_info() > doesn't. print_stop_info() doesn't. Not sure whether print_scx_info() > does. > > Maybe showing example output would help? Patch 2/9 adds this. [ https://lore.kernel.org/all/20250203141632.440554-3-bigeasy@linutronix.de/ ] This this applied, die("test") on ARM ends as: [ 1.595106] Kernel panic - not syncing: test [ 1.596044] CPU: 3 UID: 0 PID: 1 Comm: swapper/0 Tainted: G W 6.14.0-rc2-00009-gb80a798df08c-dirty #13 PREEMPT [ 1.596768] Tainted: [W]=WARN [ 1.596946] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 02/02/2022 [ 1.597407] Call trace: [ 1.598183] unwind_backtrace from show_stack+0x10/0x14 [ 1.599231] show_stack from dump_stack_lvl+0x50/0x64 [ 1.599492] dump_stack_lvl from panic+0x114/0x358 [ 1.599824] panic from kernel_init+0x64/0x74 [ 1.600048] kernel_init from ret_from_fork+0x14/0x38 [ 1.600349] Exception stack(0xdf829fb0 to 0xdf829ff8) [ 1.600730] 9fa0: 00000000 00000000 00000000 00000000 [ 1.601102] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 1.601447] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 [ 1.603163] ---[ end Kernel panic - not syncing: test ]--- Sebastian