From owner-freebsd-current@freebsd.org Sat Jul 1 14:44:18 2017 Return-Path: Delivered-To: freebsd-current@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 38FF3D8BC15 for ; Sat, 1 Jul 2017 14:44:18 +0000 (UTC) (envelope-from oleg@theweb.org.ua) Received: from oleg.opentransfer.com (oleg.opentransfer.com [91.217.144.197]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "oleg-10.opentransfer.com", Issuer "oleg-10.opentransfer.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id A8C786428B; Sat, 1 Jul 2017 14:44:17 +0000 (UTC) (envelope-from oleg@theweb.org.ua) Received: from asus.theweb.org.ua ([10.0.8.4]) by oleg.opentransfer.com (8.15.2/8.15.2) with ESMTPS id v61Ep62k006135 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Sat, 1 Jul 2017 17:51:08 +0300 (EEST) (envelope-from oleg@theweb.org.ua) Received: from asus.theweb.org.ua (localhost [127.0.0.1]) by asus.theweb.org.ua (8.15.2/8.15.2) with ESMTPS id v61Ei0hT070069 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Sat, 1 Jul 2017 17:44:00 +0300 (EEST) (envelope-from oleg@theweb.org.ua) Received: (from oleg@localhost) by asus.theweb.org.ua (8.15.2/8.15.2/Submit) id v61EhvRP070056; Sat, 1 Jul 2017 17:43:57 +0300 (EEST) (envelope-from oleg@theweb.org.ua) X-Authentication-Warning: asus.theweb.org.ua: oleg set sender to oleg@theweb.org.ua using -f From: "Oleg V. Nauman" To: Mark Millard Cc: FreeBSD Current , glebius@freebsd.org, imb@protected-networks.net, Hans Petter Selasky , iz-rpi03@hs-karlsruhe.de Subject: Re: HEAD/i386 r320212: three reproducible panics [see also bugzilla 220404 about a type of problem introduced in head -r329722 ] Date: Sat, 01 Jul 2017 17:43:57 +0300 Message-ID: <3277054.IUbe9d2na6@asus.theweb.org.ua> Organization: Private person User-Agent: KMail/4.14.10 (FreeBSD/12.0-CURRENT; KDE/4.14.30; amd64; ; ) In-Reply-To: <285F63EB-9DC3-46DC-9849-3B47FDC719AE@dsl-only.net> References: <285F63EB-9DC3-46DC-9849-3B47FDC719AE@dsl-only.net> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.23 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: Sat, 01 Jul 2017 14:44:18 -0000 On Friday 30 June 2017 22:45:39 Mark Millard wrote: > [Just for the 3rd backtrace example. . .] > > Oleg V. Nauman oleg at theweb.org.ua wrote on > Fri Jun 23 16:58:07 UTC 2017 : > > .. . . > > > __curthread () at ./machine/pcpu.h:225 > > 225 __asm("movl %%fs:%1,%0" : "=r" (td) > > (kgdb) #0 __curthread () at ./machine/pcpu.h:225 > > #1 doadump (textdump=-968633856) at ../../../kern/kern_shutdown.c:318 > > #2 0xc06e88c4 in kern_reboot (howto=) > > > > at ../../../kern/kern_shutdown.c:386 > > > > #3 0xc06e8c5b in vpanic (fmt=, > > > > ap=0xefd5c73c "\340\334\235\300\310\370\266\306\001") > > at ../../../kern/kern_shutdown.c:779 > > > > #4 0xc06e8b1b in panic (fmt=0xc092e18e "%s") > > > > at ../../../kern/kern_shutdown.c:710 > > > > #5 0xc08eed21 in trap_fatal (frame=0xefd5c878, eva=) > > > > at ../../../i386/i386/trap.c:978 > > > > #6 0xc08eea38 in trap (frame=) > > > > at ../../../i386/i386/trap.c:704 > > > > #7 > > #8 0xc6bcda1b in ?? () > > #9 0xc0770281 in unp_connect2 (so=, so2=, > > > > req=) at ../../../kern/uipc_usrreq.c:1497 > > > > #10 0xc076ff17 in unp_connectat (fd=, so=, > > > > nam=, td=) > > at ../../../kern/uipc_usrreq.c:1446 > > > > #11 0xc076d510 in unp_connect (so=0xc71c9400, nam=0xc662d500, > > > > td=) at ../../../kern/uipc_usrreq.c:1310 > > > > #12 uipc_connect (so=0xc71c9400, nam=0xc662d500, td=) > > > > at ../../../kern/uipc_usrreq.c:587 > > > > #13 0xc076a042 in kern_connectat (td=, dirfd=-100, > > > > fd=, sa=0xc662d500) at > > ../../../kern/uipc_syscalls.c:505 > > > > #14 0xc0769f49 in sys_connect (td=0xc6bcda18, uap=0xc6b6f988) > > > > at ../../../kern/uipc_syscalls.c:470 > > > > #15 0xc08ef679 in syscallenter (td=) > > > > at ../../../i386/i386/../../kern/subr_syscall.c:132 > > > > #16 syscall (frame=) at ../../../i386/i386/trap.c:1103 > > #17 > > #18 0x283a4747 in ?? () > > Backtrace stopped: Cannot access memory at address 0xbfbfe794 > > There are problems with a union having fields > that interfere with each other. The details of > the layout and interference likely vary from > TARGET_ARCH to TARGET_ARCH. This is from > new material added in head -r319722 and > involves /head/sys/sys/socketvar.h and > the new union in struct socket. > > See bugzilla 220404 and its analysis of a > repeatable crash on 32-bit powerpc for > head -r320482 (I'd made a large jump from > well before -r319722): > > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=220404 > > It also involves unp_connect2, unp_connect, > kern_connectat, sys_connect and is likely > involved. But different aliasing in the > union across architectures likely lead to > varying details for the behavior that results > from the bad handling of union use. Subscribed, thank you. > > === > Mark Millard > markmi at dsl-only.net