From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) (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 AF0D01E0DCB; Thu, 19 Jun 2025 09:10:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750324228; cv=none; b=kDZFOoY1PTS70ji5XyHSN6wcNh8Lx6O3WAfCrv+LqD+xtw75kQRZZxpve+VHItlpFpwrDuPZqVwr4BINFHs4CH+dQPS26So0PVQ226s2cqBBbxR+hFTDlDDN4uArHFH5da0Hlm1/KrAxyxbaN82CnPPX58hQLR2/0kP7vTi0Bvo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750324228; c=relaxed/simple; bh=X9Ur4oICRVpAYe+lohYqKv4M0W5+UI7MMTETEAjmmgA=; h=Date:From:To:CC:Subject:In-Reply-To:References:Message-ID: MIME-Version:Content-Type; b=UuroD/VKk5vbnzAFh9wnztCs+7KB3vmHYoNl65HpoCm1VqWpnUqzpf0fAYfeP2rV9GQAH2HGWoqZ+xYSIxJP/pC0P42Dxf4jFbaiJ8FVv4Snf5aHr3MpM9Wa3k8iDcUYW8LbO1zlWI5LKiP23GQ8e7yyqSFwSSW8VfWcyoHvD7g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 3A72A1607B5; Thu, 19 Jun 2025 09:10:24 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf20.hostedemail.com (Postfix) with ESMTPA id 05D4420026; Thu, 19 Jun 2025 09:10:20 +0000 (UTC) Date: Thu, 19 Jun 2025 05:10:20 -0400 From: Steven Rostedt To: Peter Zijlstra CC: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org, Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Ingo Molnar , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Jens Remus , Linus Torvalds , Andrew Morton Subject: =?US-ASCII?Q?Re=3A_=5BPATCH_v10_07/14=5D_unwind=5Fuser/deferre?= =?US-ASCII?Q?d=3A_Make_unwind_deferral_requests_NMI-safe?= User-Agent: K-9 Mail for Android In-Reply-To: <20250619084813.GG1613633@noisy.programming.kicks-ass.net> References: <20250611005421.144238328@goodmis.org> <20250611010428.938845449@goodmis.org> <20250619083415.GZ1613376@noisy.programming.kicks-ass.net> <20250619043733.2a74d431@batman.local.home> <20250619084427.GA1613376@noisy.programming.kicks-ass.net> <20250619084813.GG1613633@noisy.programming.kicks-ass.net> Message-ID: <66B9E72C-4FDF-46DF-9231-BED06A6000D9@goodmis.org> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Stat-Signature: 5u6tcifhicbkngw4cdyjd46w7i7yqabo X-Rspamd-Server: rspamout04 X-Rspamd-Queue-Id: 05D4420026 X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18IqjclQyx/l3AVNRVrVgUJZj9ZVpWbu7Q= X-HE-Tag: 1750324220-266712 X-HE-Meta: U2FsdGVkX19nSMfWqL4SvKuyY/SxEm8yaKdZ24faUL3mw6DIjEBvVzSdy4eLizzyBXsRqtSr/wR8M3sE3NdZfV3o3xBJwCVAX7udrhIwovODF86IS5bRRq/s58yiuQqqfschJjiQMnHnlQNfRvYMvdYeg9xEi1ZW+8b7jjC6cxJRs/ILbZr3bDaX3weqjgUuETtmQPKam0BrQphxDkSA14AiV7WuENKRqM+guMuWCZV7c6cDM5ulB3FVYG1exQMgNQENbSp6xYS4E6Qm0mJhzWHItbz4b6ij/q38s5m19FcroGV7whvFTVfgiKYZnvUEB6rrhJySry3O99uikWGjjK+5Rx7aTNaNUMVZh70RgIppVF8RX5yKchNI5WHwHHFYutH/OGemyrlmsnARNQpPTQ== On June 19, 2025 4:48:13 AM EDT, Peter Zijlstra w= rote: >On Thu, Jun 19, 2025 at 10:44:27AM +0200, Peter Zijlstra wrote: > >> Luckily, x86 dropped support for !CMPXCHG8B right along with !TSC=2E So= on >> x86 we good with timestamps, even on 32bit=2E > >Well, not entirely true, local_clock() is not guaranteed monotonic=2E So >you might be in for quite a bit of hurt if you rely on that=2E > As long as it is monotonic per task=2E If it is not, then pretty much all = tracers that use it are broken=2E -- Steve=20