From owner-freebsd-bugs@freebsd.org Thu Sep 17 07:53:47 2020 Return-Path: Delivered-To: freebsd-bugs@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 CC24F3FFCCB for ; Thu, 17 Sep 2020 07:53:47 +0000 (UTC) (envelope-from google@oprs.eu) Received: from mail-oi1-f194.google.com (mail-oi1-f194.google.com [209.85.167.194]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 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 4BsTk30rf5z4sDr for ; Thu, 17 Sep 2020 07:53:46 +0000 (UTC) (envelope-from google@oprs.eu) Received: by mail-oi1-f194.google.com with SMTP id v20so1475486oiv.3 for ; Thu, 17 Sep 2020 00:53:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=mBh9t9Ss8K6RHeh315z66bFybebUofDdcaIX9jFxW7Q=; b=lU4+dFldBT9+o+mvdOh+0LfsdyGZpsgp3kq3BEI4p0HWd0mjAhg00XPLunoRyeNo71 cVJM1i5Sog+9WPa07oa9hGfIaepmm2CQog+7BJ2w6Ed4qkUNXCPj7WOBashkkrHLLJAt 5ZfFzeyE4BugleMx0fUn4FVGrWVPkeSbKKwVBH0/kdkD8N6N/d7HKpPKQOF43ju2LERf CamwUo9wm7emIksWX/iT/Vs6ysXPCV5oAqQuVIwEKPUXiQhuKjIepH1YQVh6wzHaoN75 7Frwcp6mVdq8tYWupf6g3hDok76Ra6xiYdTVqKf1AQLmMtBYhXCXT2P60uhMsoo8Q3A3 8zPQ== X-Gm-Message-State: AOAM531tbus7FsS24JPBPd7PTEsXIyzcd5HlecYmuvU6PsUH/JsRRF49 XKJHCFJA+LCt4TVHmbn/KnoUMwz0lPEXnupm54oyhJF1u5CQ0w== X-Google-Smtp-Source: ABdhPJxX+Hx0076n3am8GnaNNTwsP/pVDF1MHydbvsoA59+oYdPEnK+N4KqW/oBiJB9xmBNHQn/JbPu8gkjFtyv3z+c= X-Received: by 2002:a05:6808:2c5:: with SMTP id a5mr5208104oid.123.1600329224944; Thu, 17 Sep 2020 00:53:44 -0700 (PDT) MIME-Version: 1.0 From: Olivier Piras Date: Thu, 17 Sep 2020 09:53:33 +0200 Message-ID: Subject: kgmon -b causes processes to crash To: freebsd-bugs@freebsd.org X-Rspamd-Queue-Id: 4BsTk30rf5z4sDr X-Spamd-Bar: +++ Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=none (mx1.freebsd.org: domain of google@oprs.eu has no SPF policy when checking 209.85.167.194) smtp.mailfrom=google@oprs.eu X-Spamd-Result: default: False [3.52 / 15.00]; RCVD_TLS_ALL(0.00)[]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_SPAM_SHORT(0.44)[0.439]; MIME_GOOD(-0.10)[multipart/alternative,text/plain]; TO_DN_NONE(0.00)[]; PREVIOUSLY_DELIVERED(0.00)[freebsd-bugs@freebsd.org]; AUTH_NA(1.00)[]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_SPAM_MEDIUM(0.96)[0.957]; DMARC_NA(0.00)[oprs.eu]; NEURAL_SPAM_LONG(0.92)[0.924]; RCVD_IN_DNSWL_NONE(0.00)[209.85.167.194:from]; R_SPF_NA(0.00)[no SPF record]; FORGED_SENDER(0.30)[freebsd@oprs.eu,google@oprs.eu]; RWL_MAILSPIKE_POSSIBLE(0.00)[209.85.167.194:from]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+,1:+,2:~]; ASN(0.00)[asn:15169, ipnet:209.85.128.0/17, country:US]; FROM_NEQ_ENVFROM(0.00)[freebsd@oprs.eu,google@oprs.eu]; MAILMAN_DEST(0.00)[freebsd-bugs]; RCVD_COUNT_TWO(0.00)[2] Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.33 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Sep 2020 07:53:47 -0000 Hi, I'm getting a strange behaviour while trying to perform some basic kernel profiling with kgmon and gprof on -CURRENT. context: . Installed last week's -CURRENT snapshot from an .iso on a spare machine. . Updated /usr/src, compiled world and the kernel (make -j4 kernel CONFIGARGS=3D-p). . rebooted, then make installworld; mergemaster -Ui . rebooted again. problem: root@current:~ # kgmon -b kgmon: kernel profiling is running. Segmentati=EF=BF=BD^3=EF=BF=BD=EF=BF=BD=EF=BF=BD oprs@current% id : jemalloc_extent.c:463: Failed assertion: "!extent_heap_empty(&extents->heaps[i])" Abort trap (core dumped) >From that point on, the system is totally unusable (processes crash repeatedly). The kernel itself seems to be running though; I can still ping the machine, in fact my ssh session is still up at this point. After rebooting (reset from kdb), dmesg shows a lot of process crashes: pid 941 (csh), jid 0, uid 0: exited on signal 11 (core dumped) pid 931 (login), jid 0, uid 0: exited on signal 11 pid 946 (getty), jid 0, uid 0: exited on signal 6 (core dumped) pid 947 (getty), jid 0, uid 0: exited on signal 6 (core dumped) pid 948 (getty), jid 0, uid 0: exited on signal 6 (core dumped) [...] My first instinct was to rebuild the kernel again, this time with world already installed, as I was suspecting some kind of inconsistency between libkvm and the kernel, but obviously the problem is still there. Am I doing something wrong here ? I'd like to get your opinion before I investigate further, and possibly create a bug report. Regards, -Olivier.