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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 818BCCD1297 for ; Mon, 10 Nov 2025 04:59:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:Mime-Version:References:In-Reply-To:Message-Id:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ui6c9sDU4Xjl521hdn4D+HAAkgKIV4EpgnYw7ivvhlA=; b=s24S1cOJYRSzEo30bUBLrTm4Ne zpGHL66SDhFkjOo8KQgDj7J0l1/1oYTu1T7UzPiT1WwYmw9iOxz9msnRySqQXvzHPEhRK2NGbc197 WxpFN3UfEpiq2SPY1n9NSeFhigbqjlmlGxqDwod2sJ3KQn9lT/eh4dDoJzpRx4I44cB8n938IeNHt RO5/QN9NeXJa5WGzB64/37WrRcs5wcwwEa858/RsfHq+btHfVzaEFwyt2wPlN69uLHoMpIDKKU4SD X0r2cpYbjNstTkW02zROr/TPzQZa79x6f7/JMQirljsnyKEzzcxVZ1KNSupmYmPYMB5hAQBQEue54 6cKyvbYg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vIJzR-00000004kKb-2lOf; Mon, 10 Nov 2025 04:58:53 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vIJzN-00000004kJH-32eo for linux-arm-kernel@lists.infradead.org; Mon, 10 Nov 2025 04:58:52 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id 84C7360008; Mon, 10 Nov 2025 04:58:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1E88C4CEF5; Mon, 10 Nov 2025 04:58:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1762750728; bh=nphcQOI1kfRbhu/YEFcCiq+ww3xH/5WIF7mQO+nNk/s=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=mpeSBHUrB/nAOomS9Mm987ApUXi1jovyAG4bwh99uEGzMB114QdOPyCRJQ9fuRbiy UbseNPen+CZyVShhms1MusQb73Tc3A1nNEtM0OqILMCVf0yx1zrsFwPYjIbKdvLMZd OkyB5VhJ1H55wWqlrAg7KcJELMO5u2v1DWbz26ILez61BWbKSmoqcaSGAg4YE5rPxS dHN0ZRmTThIuJ0cqZdxKsqG31LUYoUn6xR6Zb/wvxwiQngoWFlaKblpcwOG6wh4vwn Cf/7Qmi5D2h15g5XLyO0/gMlmPJOS7JKVtZJgfObUE+uF/8nGAtTwf4+LUjCDsYdaf Jqps5kxDE7Zsw== Date: Mon, 10 Nov 2025 13:58:44 +0900 From: Masami Hiramatsu (Google) To: Ingo Molnar , Will Deacon , Kyle Huey Cc: Peter Zijlstra , Arnaldo Carvalho de Melo , Namhyung Kim , Steven Rostedt , Mark Rutland , Alexander Shishkin , Jiri Olsa , Ian Rogers , Adrian Hunter , Mathieu Desnoyers , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Will Deacon , Catalin Marinas , linux-arm-kernel@lists.infradead.org, "Masami Hiramatsu (Google)" Subject: Re: [PATCH 0/2] tracing/wprobe: Fix to avoid inifinite watchpoint exception on arm64 Message-Id: <20251110135844.1c205d59be44d76169fc5e54@kernel.org> In-Reply-To: <176179481538.959775.12326313742393696258.stgit@devnote2> References: <176179481538.959775.12326313742393696258.stgit@devnote2> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Ingo, Will, Ping? I also found that Kyle made a change on this area recently. Thank you, On Thu, 30 Oct 2025 12:26:55 +0900 "Masami Hiramatsu (Google)" wrote: > Hi, > > Here are patches which fixes a wprobe bug reported by Mark Brown on > arm64[1]. The root cause was that the infinite watchpoint exception on > the same instruction, because arm64 watchpoint exception happens before > the memory access has done, it needs to configure a single-step after > calling overflow handler. It does that only for the default overflow > handlers, and not for custom overflow handler registered via > hw_breakpoint interface. > > [1] https://lore.kernel.org/all/aPvwGhMBJqMKcC9D@finisterre.sirena.org.uk/ > > To fix this issue, this series introduces default_overflow_compatible > flag in the perf_event and use it for identifying default overflow > handlers instead of checking handler functions everytime[1/2], and > set it in wprobe[2/2]. > > Thank you, > > --- > > Masami Hiramatsu (Google) (2): > perf: Introduce default_overflow_compatible flag > tracing: wprobe: Make wprobe_handler default overflow_handler compatible > > > include/linux/perf_event.h | 9 ++------- > kernel/events/core.c | 2 ++ > kernel/trace/trace_wprobe.c | 7 +++++++ > 3 files changed, 11 insertions(+), 7 deletions(-) > > -- > Masami Hiramatsu (Google) -- Masami Hiramatsu (Google)