From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9DE0C433DB for ; Thu, 4 Mar 2021 02:20:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A67B564FC1 for ; Thu, 4 Mar 2021 02:20:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230462AbhCDCUB (ORCPT ); Wed, 3 Mar 2021 21:20:01 -0500 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:50359 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230112AbhCDCTc (ORCPT ); Wed, 3 Mar 2021 21:19:32 -0500 Received: from compute3.internal (compute3.nyi.internal [10.202.2.43]) by mailout.nyi.internal (Postfix) with ESMTP id 2751C5C0125; Wed, 3 Mar 2021 21:18:22 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute3.internal (MEProxy); Wed, 03 Mar 2021 21:18:22 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dxuuu.xyz; h= date:from:to:cc:subject:message-id:references:mime-version :content-type:in-reply-to; s=fm2; bh=F/RocdRF7Pqs28TM5H8sAhTjZ7h Jr93UFoPWh+J/1D0=; b=IYJa6Hc7mVyAfj+W6Cizf+Cly5Vn81aImA/4slh9FTA qU3vaENIj2hEp7wyh/gmsguDkPrC3n3LQcRBTbNK6HHMwpSEbgmdw1ewyXhkOync RsAtC/ygUL9JHT5Lv8o9F2Ys4iwpob8ynMUoU2N9pXg8KD/9JueFnNGr/dW/rB7P sQh2DPDvKKbf66wOKv08FMIrIyPALi0C5mbCyCdKAh8PkK4rWIcbXDIKMg4redTY +0QvgbKGueh4vl6Xjn+VFcJfif3Kx1G/aTb0jjen6xy85i2eFeFBwN0YAxA2bIhk uPBjVC0z9RrxdhSgnWRXx8+WZK4UD/tiGrmSx36CGuQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=F/Rocd RF7Pqs28TM5H8sAhTjZ7hJr93UFoPWh+J/1D0=; b=H77+7gZme140r8DsW3ySnv OgTzSNDmUbOIhQSK+pBapV10FtOTDlrBieMHu6Zb2LrKez42x5COtzZ53NhJqxRG htnOirQaLIx30aWCouCSG/fsQpQ7FOvpgk1vi+tAgM+tcJseP3YEKmmotkug3daG m+QkXhVGYjxHq3pJW26bT6GD6OOuaDwjePJAO95P4/rwL2ZSRx5tt4QuIO9ZCMPB 0rDqiZX9LwtC/8XKtDk+XzRz7v3zJP618okWdewq4u5sCzqqxnYYgYDKbjnPh4GX 7ZsGQxBozF0mSwehH67L70rv7DBMUY5sBqJAs1njsxviLNyqCm2DzXt40oVpFcnw == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledruddtfedggedvucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddmne gfrhhlucfvnfffucdlfeehmdenucfjughrpeffhffvuffkfhggtggujgesthdtredttddt vdenucfhrhhomhepffgrnhhivghlucgiuhcuoegugihusegugihuuhhurdighiiiqeenuc ggtffrrghtthgvrhhnpeeuuddvjeefffelgfeuveehfeegfeetfeetueduudfhudfhheev leetveduleehjeenucfkphepieelrddukedurddutdehrdeigeenucevlhhushhtvghruf hiiigvpedtnecurfgrrhgrmhepmhgrihhlfhhrohhmpegugihusegugihuuhhurdighiii X-ME-Proxy: Received: from maharaja.localdomain (c-69-181-105-64.hsd1.ca.comcast.net [69.181.105.64]) by mail.messagingengine.com (Postfix) with ESMTPA id 111E61080057; Wed, 3 Mar 2021 21:18:20 -0500 (EST) Date: Wed, 3 Mar 2021 18:18:19 -0800 From: Daniel Xu To: Steven Rostedt Cc: Masami Hiramatsu , linux-kernel@vger.kernel.org, "bpf@vger.kernel.org" , kuba@kernel.org Subject: Re: Broken kretprobe stack traces Message-ID: <20210304021819.hgam3z3xurxcq3re@maharaja.localdomain> References: <1fed0793-391c-4c68-8d19-6dcd9017271d@www.fastmail.com> <20210303134828.39922eb167524bc7206c7880@kernel.org> <20210303092604.59aea82c@gandalf.local.home> <20210303195812.scqvwddmi4vhgii5@maharaja.localdomain> <4d68e8d9-38b0-4f32-90b6-1639558fce51@www.fastmail.com> <20210303153740.4c0cc0c5@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210303153740.4c0cc0c5@gandalf.local.home> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 03, 2021 at 03:37:40PM -0500, Steven Rostedt wrote: > On Wed, 03 Mar 2021 12:13:08 -0800 > "Daniel Xu" wrote: > > > On Wed, Mar 3, 2021, at 11:58 AM, Daniel Xu wrote: > > > On Wed, Mar 03, 2021 at 09:26:04AM -0500, Steven Rostedt wrote: > > > > On Wed, 3 Mar 2021 13:48:28 +0900 > > > > Masami Hiramatsu wrote: > > > > > > > > > > > > > > > > > > > > > I think (can't prove) this used to work: > > > > > > > > Would be good to find out if it did. > > > > > > I'm installing some older kernels now to check. Will report back. > > > > Yep, works in 4.11. So there was a regression somewhere. > > Care to bisect? ;-) Took a while (I'll probably be typing "test_regression.sh" in my sleep tonight) but I've bisected it down to f95b23a112f1 ("Merge branch 'x86/urgent' into x86/asm, to pick up dependent fixes"). I think I saw the default option for stack unwinder change from frame pointers -> ORC so that may be the root cause. Not sure, though. Need to look more closely at the commits in the merge commit. <...> Daniel