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 D11E730F547; Thu, 9 Apr 2026 08:29:58 +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=1775723398; cv=none; b=fzQPi4pOhKzmjQH/WlMbJGC6oAioedMVR1FqP2Tnsvz3n/gZk0w9HcaGw/bKJDZyMY3ucDrmpvSo5Nkz7T61guOi7n64Ozy1kKF6m52XBhNLRzdETL60tB3wbiIKzWgnAOr4TCKCN40uHMgdYmIan7DVGGXdKaO88RuMoW8Z6jE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775723398; c=relaxed/simple; bh=90J5dcfEqJG4NnUKBW+CcbW1udft49rP02t6iqdqqMA=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=DYo7yRlcNgXZOxtyzuVv39Nty6B5neZZX5s4FwCXLa/BNR1CL3efp3XoP9BcOUjgFw/8kW+g3y9U+USzP8vx88x+fom1nXU5A0N1u65s2ugtElMyHWIDTyCXT0bin+Tw2SPOwr+yCoijbYxIi6PDH+VAjrqhm16vo4Rp1LOKKZo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Td+xSAcb; 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="Td+xSAcb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5FA41C4CEF7; Thu, 9 Apr 2026 08:29:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775723398; bh=90J5dcfEqJG4NnUKBW+CcbW1udft49rP02t6iqdqqMA=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Td+xSAcb0HzHDfuaJow2c9iq30FYW8xG98M8Jas8AAvcLrBe2iMcNDeOWmsnrLa96 ApNFD9C3W5dMhN0RNmajj865lSI32ldRvRo1O9OV6SdM4kHeMhat3LV7xU1jxVvP8R 6QSoXl29YCDlBuTEZ0f5QXqgSENsm3WjJPeu3UpKBWHfGXG2p1soJK99si+2b4Cmc7 BlJMg9Zp0WFsVTGQmrpehjYwp6aLOn7nr53b+y4Hg7mX54rAKGZX8RviJnOcXysBe/ IyyRgJrbuGyHtTnTIYKaV8bT9waqYb+S8Ml/kyU4dha6HmK3tkJvgZLRaezNPe2xwD QajDQ0EJYVjfA== Date: Thu, 9 Apr 2026 17:29:55 +0900 From: Masami Hiramatsu (Google) To: Cao Ruichuang Cc: rostedt@goodmis.org, mathieu.desnoyers@efficios.com, shuah@kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH] selftests/ftrace: Account for fprobe attachment at creation Message-Id: <20260409172955.98e2d20a7f7736a1a9834816@kernel.org> In-Reply-To: <177571189990.17594.14983613605049028604@163.com> References: <20260407115751.96184-1-create0818@163.com> <20260408094920.417cbb5e64220afc2bf1b2aa@kernel.org> <177571189990.17594.14983613605049028604@163.com> X-Mailer: Sylpheed 3.8.0beta1 (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 Thu, 09 Apr 2026 13:18:19 +0800 Cao Ruichuang wrote: > Hi Masami, > > I reran this in a clean QEMU boot environment with only the minimal > tracefs setup and the add_remove_fprobe sequence. > > I saw the same behavior there: after creating myevent1/2/3, > enabled_functions went from 2 to 4 before any event was enabled, and > enabling myevent1/2/3 did not increase the count further. After cleanup, > it returned to the original baseline again. Hmm, that does not mean test failure but could be a bug. Can you dump the enabled_functions and share it when the test failed? > So this does not look like a dirty tracing environment issue. The > failing testcase assumption appears to be that the attachment happens on > enable, while on the current kernel it is already visible after create. What kernel are you using? I need to check why this happens. I guess there is a change which introduces this issue. Thank you, > > Thanks, > Cao Ruichuang > -- Masami Hiramatsu (Google)