From owner-freebsd-current@freebsd.org Tue Nov 5 18:22:16 2019 Return-Path: Delivered-To: freebsd-current@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id B95C21B006F for ; Tue, 5 Nov 2019 18:22:16 +0000 (UTC) (envelope-from markjdb@gmail.com) Received: from mail-qk1-x741.google.com (mail-qk1-x741.google.com [IPv6:2607:f8b0:4864:20::741]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 476ygW6v2jz3N2X for ; Tue, 5 Nov 2019 18:22:15 +0000 (UTC) (envelope-from markjdb@gmail.com) Received: by mail-qk1-x741.google.com with SMTP id i19so12938002qki.2 for ; Tue, 05 Nov 2019 10:22:15 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=YCcUpewmaYssxBlffsrLmYPNIG5E93qZeM9xZMWfzWY=; b=HoHEfhMwQiD3tVqc+cPmn367+Nqup/7nKQupGngVGR1eV5w8H/9iz8fwwHqYxMPayo wfd6p9QEDLxYqnmaieOuxHg0Zji+HC34aas2j5ezs+mwnuj90917i+rg6PhtyHaq7632 yDm4od4K05H6fkk1tsHmlb9wj46UTr0HOReAYjh8fBK0ojjUzqehPq4D34qhXewB3ImG /UZ3NDCwIXcF9PhV56V367qebEUoyrxM66eji7s3DgF89PwQ5jXLExcnN3QyH0OQMEjK mqpavW297kUuXWErMVouC5oQDI8Z2+JFxVysrjcOjiZm04gvxFn1HrphcfK8lJdYFagg +kug== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to:user-agent; bh=YCcUpewmaYssxBlffsrLmYPNIG5E93qZeM9xZMWfzWY=; b=Sqi0eOU8k9kDC0Pk6v3DNtCpjNFiSJBIC/xeZkztoRlcMcnTw0MwRpKm3HosT39bZi Qo1hrYw18Em4DncMtyH+y7LZuQ6g89qiIUdB4sC6Dj+gi8jChVOanULzsJOPlMtG7WcC zgcRUgb6ivkFJQ7E7PiBz9D4N8Qx0vQ0ddhwCmLAByx+SpoXtIPdF9ese8Ua3wopgtTU 2DtFKB0FS+xwkBuitktsC6/4cb8x9uc6jkhFAMkTR5T8jNqu9E6/F0c/SM9QLKSq+re2 cQlgZmTjDfw+wKJOKqAw9LxcibuB5LoWviNMWJXVhNUUk9OLoKybJDUku+WlsJHTaQBy /9og== X-Gm-Message-State: APjAAAVlXUdtRJt+2Q0UtSNbQWLie41hNajj9BtsMiukyhxYxdKePXV7 rpGlbWDqaJkPB/vO9pGEadT+6JrtPBY= X-Google-Smtp-Source: APXvYqxuc1mxPQ04pUkf55JmaUGuxjVFwX745upoE1nBrhPrAEZcsT9QA2gVhmx7Na3mgnHqIOA7jw== X-Received: by 2002:a37:a58b:: with SMTP id o133mr10806335qke.418.1572978134893; Tue, 05 Nov 2019 10:22:14 -0800 (PST) Received: from raichu (toroon0560w-lp130-05-69-158-183-252.dsl.bell.ca. [69.158.183.252]) by smtp.gmail.com with ESMTPSA id u11sm8790140qtg.11.2019.11.05.10.22.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 05 Nov 2019 10:22:14 -0800 (PST) Sender: Mark Johnston Date: Tue, 5 Nov 2019 13:22:12 -0500 From: Mark Johnston To: Brennan Vincent Cc: freebsd-current@freebsd.org Subject: Re: Kernel panics sometimes resulting in no core dump. Message-ID: <20191105182212.GB96050@raichu> References: <9C7D409D-7305-4E3A-9F66-F518A8D321B8@umanwizard.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <9C7D409D-7305-4E3A-9F66-F518A8D321B8@umanwizard.com> User-Agent: Mutt/1.12.2 (2019-09-21) X-Rspamd-Queue-Id: 476ygW6v2jz3N2X X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20161025 header.b=HoHEfhMw; dmarc=none; spf=pass (mx1.freebsd.org: domain of markjdb@gmail.com designates 2607:f8b0:4864:20::741 as permitted sender) smtp.mailfrom=markjdb@gmail.com X-Spamd-Result: default: False [-2.09 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20161025]; NEURAL_HAM_MEDIUM(-1.00)[-0.999,0]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2607:f8b0:4000::/36:c]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-current@freebsd.org]; DMARC_NA(0.00)[freebsd.org]; RCVD_COUNT_THREE(0.00)[3]; MIME_TRACE(0.00)[0:+]; TO_MATCH_ENVRCPT_SOME(0.00)[]; DKIM_TRACE(0.00)[gmail.com:+]; RCPT_COUNT_TWO(0.00)[2]; RCVD_IN_DNSWL_NONE(0.00)[1.4.7.0.0.0.0.0.0.0.0.0.0.0.0.0.0.2.0.0.4.6.8.4.0.b.8.f.7.0.6.2.list.dnswl.org : 127.0.5.0]; IP_SCORE(-0.39)[ip: (2.46), ipnet: 2607:f8b0::/32(-2.36), asn: 15169(-2.02), country: US(-0.05)]; FORGED_SENDER(0.30)[markj@freebsd.org,markjdb@gmail.com]; MID_RHS_NOT_FQDN(0.50)[]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:2607:f8b0::/32, country:US]; FROM_NEQ_ENVFROM(0.00)[markj@freebsd.org,markjdb@gmail.com]; RCVD_TLS_ALL(0.00)[] X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 05 Nov 2019 18:22:16 -0000 On Tue, Nov 05, 2019 at 12:44:06PM -0500, Brennan Vincent wrote: > (Note: I have also posted this to the forums, but upon reading the forum guidelines more carefully I realized the mailing list is probably a better venue. So if you are also a forum reader, I apologize for the extra churn.) > > Hello, I am running 13-CURRENT (compiled recently from source using default build settings) and recently I have been kernel panics every so often. They can happen at any time but seem to be more likely when the system is running a graphical environment and is at high load (e.g., during `make -j64 buildworld`). > > I have configured my system to collect core dumps: my swap partition is 50 GB (large enough to contain any conceivable minidump), `dumpon` reports that it is indeed configured as a dump partition, and I have `savecore_enable="YES"` in /etc/rc.conf. I also have the sysctl `debug.debugger_on_panic` set to 0, which seems to be necessary for core dumps to happen (instead of breaking into the debugger on panic). Before, when that sysctl was set to 1, my graphical environment would hand; now it reboots. The changing behavior depending on the value of `debug.debugger_on_panic` is what makes me think this really is a kernel panic, as opposed to some other possible issue that could cause a crash. > > The weird thing is that when I manually cause a panic via `sudo sysctl debug.kdb.panic=1` , my system reboots as expected, and a core dump **does** get generated and saved in /var/crash! So it's only the mysterious random crashes that aren't causing core dumps. > > Can anyone help me figure out why core dumps are not getting generated, and how I can possibly debug what is going on? Are you using one of the DRM graphics drivers? I've found that setting dev.drm.skip_ddb="1" in loader.conf is sometimes necessary.