From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out30-100.freemail.mail.aliyun.com (out30-100.freemail.mail.aliyun.com [115.124.30.100]) (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 27216443C34; Thu, 8 Oct 2026 11:47:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=115.124.30.100 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791460071; cv=none; b=k8Pv6uw8ifoqIIEJOzIoYgmmo5AopaSZYlzJSP2DAeO3Y+1XTmRfwplCc/Vn62+vuNRpvsDy7IqOLput02xyvIdEa/5SixvVPXmzbp/82zx2ebMgztGqOd9iAbyawjgE2LotRQ8lf2FpS84LQeNbAqEGC7BdjCTt9eSqyXGy1fk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791460071; c=relaxed/simple; bh=OUNZ/VZ8OrrRrCTA8+5HB6ElWjtVTJ5aPjr31lVAvcA=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=u7BN8Ue3ZXfPAHP4kAHtQcl4N/6zfCbhw4zCycXWzPHWApjOG+sEJhKCJ5LvuXIJBDTuzHuUaciMi8jDubHuanlxDZEJvBcArVt/UUTigE6Mldg1LQJYlMQ5NKKoTrQBS+8ucrYm1J1g7kZL/k3F1mU/4WNfpI/N1wAUFm/GwT0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com; spf=pass smtp.mailfrom=linux.alibaba.com; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b=d9SfD7/i; arc=none smtp.client-ip=115.124.30.100 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.alibaba.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.alibaba.com header.i=@linux.alibaba.com header.b="d9SfD7/i" DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1791460059; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=2uRUiMGM/3kM5oFgvWkstit41ISjJ8dKFkmnjBOgzTY=; b=d9SfD7/i3F8/7mhWPtNs4PbENsPzHePZ1tusqOfNzF5OEb5MFFoyDHTotZ1yhdHWLAPcOqQcJ7vrppp+F7wUyLx6J0Kmq+NKypSW6hYOV3xee4wMei9wClqocofEV3QaqZCjRJjxL3enc1nYpJX9r9cQ+T9pDtH57kKkJMPiO58= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R191e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037009110;MF=xueshuai@linux.alibaba.com;NM=1;PH=DS;RN=34;SR=0;TI=SMTPD_---0XCP.Q2W_1791459729; Received: from 30.246.161.100(mailfrom:xueshuai@linux.alibaba.com fp:SMTPD_---0XCP.Q2W_1791459729 cluster:ay36) by smtp.aliyun-inc.com; Thu, 08 Oct 2026 19:42:10 +0800 Message-ID: Date: Thu, 8 Oct 2026 19:42:08 +0800 Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 0/7] riscv: Add reliable stack unwinding for livepatch To: Martin Kaiser , Palmer Dabbelt , Paul Walmsley Cc: pjw@kernel.org, aou@eecs.berkeley.edu, alex@ghiti.fr, linux-riscv@lists.infradead.org, oleg@redhat.com, rostedt@goodmis.org, mhiramat@kernel.org, mark.rutland@arm.com, peterz@infradead.org, mingo@redhat.com, acme@kernel.org, namhyung@kernel.org, alexander.shishkin@linux.intel.com, jolsa@kernel.org, irogers@google.com, adrian.hunter@intel.com, james.clark@linaro.org, jpoimboe@kernel.org, jikos@kernel.org, mbenes@suse.cz, pmladek@suse.com, joe.lawrence@redhat.com, shuah@kernel.org, mpdesouza@suse.com, oliver.yang@linux.alibaba.com, zhuo.song@linux.alibaba.com, jkchen@linux.alibaba.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, live-patching@vger.kernel.org, linux-kselftest@vger.kernel.org References: <20260914092648.51254-1-xueshuai@linux.alibaba.com> From: Shuai Xue In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/29/26 3:28 PM, Martin Kaiser wrote: > Thus wrote Shuai Xue (xueshuai@linux.alibaba.com): > >> Hi, > >> This is v6 of the RISC-V reliable stack unwinding series for livepatch. >> Wang Han has left our team, so I am taking over this series from now on. > >> The series adds explicit frame-record metadata, preserves the frame >> pointer through dynamic ftrace, and replaces the open-coded stack walker >> with a conservative frame-pointer based unwinder. It then enables the >> RISC-V livepatch capability and adds the syscall-wrapper selftest prefix. > >> Changes since v5: >> * Rebase onto the current riscv/for-next; no functional changes. >> * Fold in the tags collected from the v5 thread: >> - Reviewed-by: Shuai Xue on 2/7, 3/7, 4/7 and 6/7 >> - Acked-by: Miroslav Benes on 7/7 >> * Add my sign-off as the new sender. > >> Since the patches are otherwise identical to v5, the v5 validation >> results still apply. For reference, from the v5 cover letter: >> * Built Linux 7.2.0-rc6 with riscv64-unknown-linux-gnu-gcc 15.2.0 >> and binutils 2.46. >> * Standard livepatch configuration built successfully, including >> Image, vmlinux, modules, compile_commands.json and GDB scripts. >> * CONFIG_IRQ_STACKS=n variant linked successfully with GCC. >> * QEMU 8.2.2, 1 CPU: livepatch selftests PASS: 7, SKIP: 1, >> FAIL: 0; ftrace function graph 3 passed, 0 failed, 3 unsupported. >> * QEMU 8.2.2, 4 CPUs: livepatch selftests PASS: 7, SKIP: 1, >> FAIL: 0; ftrace function graph 3 passed, 0 failed, 3 unsupported. >> * No BUG, WARNING, Oops, panic, unreliable stack or Call Trace found >> by the validation log scans. Expected negative livepatch errors are >> part of the selftests. > >> v5 was posted in early August and has been quiet since then. I would >> appreciate it if the series could be considered for the upcoming merge >> window. Happy to address any remaining feedback. > >> Base: >> riscv/for-next 77ae27fd98f3 ("Merge tag 'printk-for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux") > >> Previous versions: >> v5: https://lore.kernel.org/r/20260804103626.2803112-1-wanghan@linux.alibaba.com >> v4 RESEND: https://lore.kernel.org/r/20260629072713.3273743-1-wanghan@linux.alibaba.com >> v3: https://lore.kernel.org/r/cover.194d76e3a15b.v3.riscv-livepatch.wanghan@linux.alibaba.com >> v2: https://lore.kernel.org/r/20260528082310.1994388-1-wanghan@linux.alibaba.com >> v1: https://lore.kernel.org/r/20260527123530.2593918-1-wanghan@linux.alibaba.com > >> Assisted-by: Qoder:Qwen-3.8-MAX-Preview > > Thanks for these patches. > > I tried them on a standard rv64 qemu and on a rv64 cheri system > (cheri-linux.org). The latter needed some minor tweaks, but in > both cases, I could get livepatch to work. > > Reviewed-by: Martin Kaiser > Tested-by: Martin Kaiser Hi Martin, Thank you very much for testing the series and for the tags! It is great to hear that livepatch works both on a standard rv64 QEMU and on the rv64 CHERI system. Could you share what the minor tweaks for CHERI were? If any of them are generic -- for example frame-record size/alignment or pointer-width assumptions in the unwinder -- it may be worth folding them into this series, so the cheri-linux tree has less to carry downstream. If they are purely CHERI-specific, a pointer to your tree would still be a useful reference. +Palmer, Paul, gentle ping on this series. It has been under review since late May (v1 on May 27, now in its sixth revision) and the tags collected so far are: * Acked-by: Miroslav Benes (7/7, livepatch) * Reviewed-by: Marcos Paulo de Souza (7/7) * Reviewed-by: Martin Kaiser (whole series) * Tested-by: Martin Kaiser (whole series, rv64 QEMU and rv64 CHERI, livepatch working on both) * Reviewed-by: Shuai Xue (2/7, 3/7, 4/7, 6/7) v6 still applies cleanly onto the current riscv/for-next (52318cf0fa6e). If it helps, I can send a v7 that folds in Martin's Reviewed-by/Tested-by tags. Could the series be considered for the upcoming 7.4 merge window? Thanks, Shuai Xue