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 5857F623; Tue, 30 Jul 2024 13:04:24 +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=1722344665; cv=none; b=KadhSg9JOSSQlgPTTtag6XYl0eQz+YdqDKZR+5i20RBWdUAzwP5vM3RQjHAE4NKKXisVu6XDLq2p9MqhRkGAWXaY+tl28aUuaGv6EEkUehj1Oj6gctH79wAQ6UhLjBdqmLVGp302+oM6nmVXkQ+mNX67/GgNJ1pymdpElt/yNSI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722344665; c=relaxed/simple; bh=Vds91/wtGjgWmouaxLlCIsUy+law5p/u5wFwIQDfHaU=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=EW9oSL/IFAS/VnrES/0WsOqGzLWhrRln/sQZXBLQXSiv4dKJUVF4U2fG1y5aMnDR9lASEkvWJ+IgjhzbO3k2teU3sDq9UK/dA6XebfT+auN+uHlf/o+S5FaIA2mAWnwujbREnYz+5TXFdChZDq0DP6Zg2+ocAbEiPNI0qlcj+ag= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=kfHN9phs; 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="kfHN9phs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 210EFC32782; Tue, 30 Jul 2024 13:04:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722344664; bh=Vds91/wtGjgWmouaxLlCIsUy+law5p/u5wFwIQDfHaU=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=kfHN9phsPk9frydWNCHlfkOLGu1hsD7bZCcTVbqpHQnGCM41VuzFJjkYE2djFG/uU 2uQNIzZEO4uRvgdwdthH5H8IGcbtGoX+ECVQ7fnSmod/4yUb+NuLhkvM5n34ZEzfAH 3hmavpi+iGBFebQcExbEO1JQAuTUVuJgVuQId4WL+Bx6QxwllIXLF6S73YIb/h9OFN X8WN8M8qvMoZNG4Fxy0d5lpg6G3GUvkFch1inmJZhaWgfPsUgQHnX/uBIhEx8+Boew L0NAa7sO5Ufy370etXsv1fB27rAPYtcQLMAv8SU1XjK1QMAutFY5nt8cwOOhv71z42 bhpJniyvcYe8Q== Date: Tue, 30 Jul 2024 22:04:17 +0900 From: Masami Hiramatsu (Google) To: Song Liu Cc: live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, jpoimboe@kernel.org, jikos@kernel.org, mbenes@suse.cz, pmladek@suse.com, joe.lawrence@redhat.com, nathan@kernel.org, morbo@google.com, justinstitt@google.com, mcgrof@kernel.org, thunder.leizhen@huawei.com, kees@kernel.org, kernel-team@meta.com, mmaurer@google.com, samitolvanen@google.com, mhiramat@kernel.org, rostedt@goodmis.org Subject: Re: [PATCH 3/3] tracing/kprobes: Use APIs that matches symbols with .llvm. suffix Message-Id: <20240730220417.33bd5f0d75c3742c413136d1@kernel.org> In-Reply-To: <20240730005433.3559731-4-song@kernel.org> References: <20240730005433.3559731-1-song@kernel.org> <20240730005433.3559731-4-song@kernel.org> X-Mailer: Sylpheed 3.7.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-trace-kernel@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 Mon, 29 Jul 2024 17:54:33 -0700 Song Liu wrote: > Use the new kallsyms APIs that matches symbols name with .llvm. > suffix. This allows userspace tools to get kprobes on the expected > function name, while the actual symbol has a .llvm. suffix. > _kprobe_addr@kernel/kprobes.c may also fail with this change. Thanks, > This only effects kernel compared with CONFIG_LTO_CLANG. > > Signed-off-by: Song Liu > --- > kernel/trace/trace_kprobe.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index 61a6da808203..c319382c1a09 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -202,7 +202,8 @@ unsigned long trace_kprobe_address(struct trace_kprobe *tk) > > if (tk->symbol) { > addr = (unsigned long) > - kallsyms_lookup_name(trace_kprobe_symbol(tk)); > + kallsyms_lookup_name_or_prefix(trace_kprobe_symbol(tk)); > + > if (addr) > addr += tk->rp.kp.offset; > } else { > @@ -766,8 +767,13 @@ static unsigned int number_of_same_symbols(const char *mod, const char *func_nam > { > struct sym_count_ctx ctx = { .count = 0, .name = func_name }; > > - if (!mod) > + if (!mod) { > kallsyms_on_each_match_symbol(count_symbols, func_name, &ctx.count); > + if (IS_ENABLED(CONFIG_LTO_CLANG) && !ctx.count) { > + kallsyms_on_each_match_symbol_or_prefix( > + count_symbols, func_name, &ctx.count); > + } > + } > > module_kallsyms_on_each_symbol(mod, count_mod_symbols, &ctx); > > -- > 2.43.0 > -- Masami Hiramatsu (Google)