From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mta0.migadu.com (out-242.mta0.migadu.com [91.218.175.242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C10AB445AF6 for ; Wed, 12 Aug 2026 13:13:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.242 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786540410; cv=none; b=YSTHPH/m/0BlTBbecZ9hMGExhUBnc2BWFUWcmkphTi9sUP8EBurDikl5zgNViE8x35cIaezvWsVd8anjgNHEEM9wKjdCoBw2IoRjkzMiaVBVXMm8u5tQmkyv9HajyUNhMR927UP+QM+liWOTSGsL2ciAwByFXty8OBob7RzPyNs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786540410; c=relaxed/simple; bh=7NbnZ3oa/RtGinQgKVF9pKDMVERXfqX9/LOk9QyatAs=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=cnuFOl6d48Iw4JE2KP3Pyp+6MUfE4VLudIYjIpmAZA1lTl7nIGd/oWk2NLWT2ip2vAPlZbW9yOJ0N+Cf4Cw61DLMjnSpI9Rbjh8rtliFpC9y/umeck8SxBiAh5/sQZZuFpOJRyKdpmgjqkqZx8Hbfd+nJSWBvUnKz5W7Io+iwcQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=lvuqJamf; arc=none smtp.client-ip=91.218.175.242 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="lvuqJamf" X-Envelope-To: linux-kernel@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=7NbnZ3oa/RtGinQgKVF9pKDMVERXfqX9/LOk9QyatAs=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1786540406; v=1; x=1787145206; b=lvuqJamfxASnuuzwCd7cyQM0Z5BLRyt9NrIJ6PnfMfQeHV8V1tlFXa/OVEAOtwC+ldnVtsL2 8umyFKHZKediIRklOJJkjIYttu49vO8qZRUlvJ1hrvforo9t7IT7GIvVaCQ2QME+Ud+FA7BjGOX 8riMOxU45MW5a/RdLt0POz/s= X-Envelope-To: linux-kernel@vger.kernel.org Received: from linux.dev (54.71.19.239) by smtp.migadu.com with ESMTPS id ee06e5b49e57f9a5; Wed, 12 Aug 2026 13:13:26 +0000 Date: Wed, 12 Aug 2026 13:13:12 +0000 From: "Jose Fernandez (Anthropic)" To: Mark Rutland Cc: Steven Rostedt , Masami Hiramatsu , Catalin Marinas , Will Deacon , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Sami Tolvanen , Leon Hwang , Ihor Solodrai , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev, bpf@vger.kernel.org, Florent Revest , Puranjay Mohan , Xu Kuohai Subject: Re: [PATCH 0/2] arm64: ftrace: support DIRECT_CALLS without CALL_OPS Message-ID: References: <20260609-arm64-ftrace-direct-calls-v1-0-4a46f266697f@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Wed, Jul 29, 2026 at 02:02:52PM +0000, Jose Fernandez (Anthropic) wrote: > One idea I would like your opinion on is an in-range > allocation preference for BPF trampolines, since execmem seems to > have the shape for it on arm64 already. [...] Hi Mark, Quick update on this, also for the others on the thread waiting on the perf side. After some internal discussion we decided to try adding CALL_OPS support on kCFI kernels directly, instead of the in-range allocation above. The section argument Sami added to -fpatchable-function-entry in clang 21 turns out to be enough to do it with kernel changes only. We have it working as a local series and I plan to send it as an RFC in the next couple of weeks. Mentioning it now in case you are already looking at this or have thoughts before then. Thanks, Jose