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 9B149EE01F8 for ; Wed, 11 Sep 2024 00:41:13 +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=be/lBKLkJBm4wBZxOWo0wUi469hne3ePmwLEGbLfpWc=; b=rNOCpJGTig5ViNJuTVedd6XEXm gsUV3ZmpB97Z4c+TLg2uqprtWa29bJsm7YT7cfj+OXKPB1evwNxAzmmQtSq9q6xO6Zt+mYZEjknuW TFjHGkReWnitZg/tQJ6zhSOUNUjcMmzWhN9kbAeHWCH3BJiF+5QCCKbAa5W/V2gb3JB04p9yTqvo5 lzq6jLVgaJgNli2B6mTO9bXMdbvxcLut92xRUf/obrOvmAFIeIIoI25TO/WpIWWzkdLuJePIxfSSA rLwEeTsZHU0l773207NJG+qUt/RLXHiWBIWnGNUyQrIJ21boYNmQtqOWmj4EmvkW+elqYknGPaUm5 Mt6E/mrg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1soBPo-00000007cUB-1usx; Wed, 11 Sep 2024 00:41:00 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1soBOm-00000007cMb-24Cs for linux-arm-kernel@lists.infradead.org; Wed, 11 Sep 2024 00:39:58 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 0FBF6A43FD2; Wed, 11 Sep 2024 00:39:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BFBE4C4CEC3; Wed, 11 Sep 2024 00:39:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726015195; bh=/fBDpPiu3lGHYDzGSOLr2nCGAJ0lbLinn72VPH8yw4U=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NDHN0VU14VplbHJbatz0aF9iTnC0LJne7hqG/Os83afPXIv/xvjD7G7fqIy31pT1E MGq9Fyilb5XGLAeM+AlG8wjuD9s6KfmLwnqh3qhkGR5h7boQnt3+CeERiIDjwwDuDB 1ODWrwjxGxTpW8vAqKphnEuYaAXOGl98YZJ0OTkeuMPLutqojv/ZE7bldUXbefcASD 3yeaYSu41uhSTnngfAY6DNzoRZyQiGy1J8phr+B5Ld2b9F15vHcD3+yCzZ5tls1m/m 2hhqSjmSG9YMgkMbya6FmdFaCjt4dBXUEEQX/W/mTD0bP3vvzeu5mnao0XFI0+lE4y Q4bd/jxlBxnIw== Date: Wed, 11 Sep 2024 09:39:49 +0900 From: Masami Hiramatsu (Google) To: Andrii Nakryiko Cc: Steven Rostedt , Masami Hiramatsu , bpf , Linux trace kernel , adubey@linux.ibm.com, "Naveen N. Rao" , KP Singh , linux-arm-kernel , Mark Rutland , Will Deacon , Alexei Starovoitov , Catalin Marinas , Florent Revest , Puranjay Mohan Subject: Re: Unsupported CONFIG_FPROBE and CONFIG_RETHOOK on ARM64 Message-Id: <20240911093949.40e65804d0e517a1fa1cba11@kernel.org> In-Reply-To: References: <20240910145431.20e9d2e5@gandalf.local.home> X-Mailer: Sylpheed 3.7.0 (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-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240910_173956_656684_CD2AD8A3 X-CRM114-Status: GOOD ( 15.15 ) 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 On Tue, 10 Sep 2024 13:29:57 -0700 Andrii Nakryiko wrote: > You are probably talking about [0]. But I was asking about [1], i.e., > adding HAVE_RETHOOK support to ARM64. Despite all your emotions above, > can I still get a meaningful answer as for why that wasn't landed and > what prevents it from landing right now before Masami's 20-patch > series lands? As I replied to your last email, Mark discovered that [1] is incorrect. From the bpf perspective, it may be fine that struct pt_regs is missing some architecture-specific registers, but from an API perspective, it is a problem. Actually kretprobes on arm64 still does not do it correctly, but I also know most of users does not care. So currently I keep it as it is. But after fixing this issue on fprobe. I would like to update kretprobe so that it will use sw-breakpoint to handle it. It will increase the overhead of kretprobe, but it should be replaced by fprobe at that moment. Thank you, > > [0] https://lore.kernel.org/linux-trace-kernel/172398527264.293426.2050093948411376857.stgit@devnote2/ > [1] https://lore.kernel.org/bpf/164338038439.2429999.17564843625400931820.stgit@devnote2/ > > > > > Again, just letting you know. > > > > -- Steve -- Masami Hiramatsu (Google)