From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 837F04A29; Wed, 11 Sep 2024 23:53:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726098832; cv=none; b=UF/PYpHeqgmWelTb7Qfx89nMEpWPvX/KXb8eD3+/GraMJe2ql8/zZgUwb9NYOjVtjBRkmpYQI2EC2TpkQ8/JbtLd77tjmPK0g3h60MTZB6LZZ6ZNEhFm+rcQRJe38OhgSgestueuQ+8kMWSvgIt8//Lx1jyXwXd+0dgyyoRj/10= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1726098832; c=relaxed/simple; bh=ewXwRnugXYXsCY1PEPRe8FMZ36d1aPzdmQ+2IRD3E9Y=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=YW/IOWkDqN/RmUAr5U3XnbV4opOv1hxh+xzSrO4auybFv+9rVHnY3TMiDgNcj0U71o+Ed8VLnmVY4JA4uLTW6ulWn6GNKLx/k1eraFPgxDAomRHOvAKNE2u/rs9JVZrBqzgConUIyYu8Wsuj5laFrLweWiW9uBs2zGBL0MQXwek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kaZCSVQO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="kaZCSVQO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE15EC4CEC0; Wed, 11 Sep 2024 23:53:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1726098832; bh=ewXwRnugXYXsCY1PEPRe8FMZ36d1aPzdmQ+2IRD3E9Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=kaZCSVQO0u6e+HbGwoP4zYmk/jYQzfn5J732qvCqqSPW8stpMt8w5hrBnXi7Dz3G/ NvbDtN5fKUKfkJCUd74GRfgrFSnZH6L03ekj8Jh4vF//7vX/vxDni+iZpwfVbG912M ID1CzANATF3wV+55XPl03UjM6ErAAbr580xRA9QjF22hFoaoIFt0mxE4CfD0B9+HDv HZLk6XMrUW+LQaYkOD4L8m79USeoTSJTXj9t0M7SFO1wSa3icN4Kp6u8vUabGBcBJL 8cpZhcywe6DIyWmmIIXKGy2kW54GVy+s6n61Sv0bThZA7smsZdiNPpAfdNorxykaIV 741p9enWKkYXw== Date: Thu, 12 Sep 2024 08:53:46 +0900 From: Masami Hiramatsu (Google) To: Andrii Nakryiko Cc: Mark Rutland , Jiri Olsa , Steven Rostedt , bpf , Linux trace kernel , adubey@linux.ibm.com, "Naveen N. Rao" , KP Singh , linux-arm-kernel , Will Deacon , Alexei Starovoitov , Catalin Marinas , Florent Revest , Puranjay Mohan Subject: Re: Unsupported CONFIG_FPROBE and CONFIG_RETHOOK on ARM64 Message-Id: <20240912085346.154b18ca686c7c4595e93c9a@kernel.org> In-Reply-To: References: <20240911091343.77c60bc2e5d96cbfd8787c19@kernel.org> <20240912001848.d9629a1579ea3ef6531a9a0b@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 11 Sep 2024 13:18:12 -0700 Andrii Nakryiko wrote: > > > So while I get the desire to have a clean and nice > > > end goal, and that it might take a bit longer to get everything right. > > > But, maybe, landing a stop-gap solution meanwhile (especially as > > > isolated and thus easily backportable as the patch [0] you referenced) > > > is an OK path forward? > > > > I had not realized that the PSTATE register was not saved correctly > > at that point. This is one reason why I decided to move in the > > current fprobe-on-fgraph direction. > > Sure, but you said yourself, the same problem exists with current > kretprobe implementation, so this won't regress anything. And yes, > your fprobe-on-fgraph series is supposed to fix this for good, which > is great, but that's a separate topic. It does not regress kretprobe, but introduces the same problem to fprobe. And since fprobe-on-fgraph was boosted by this problem, I think that is not a separate topic. Thank you, -- Masami Hiramatsu (Google)