From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) (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 F00AF3C33; Sat, 30 Aug 2025 01:25:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.17 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756517152; cv=none; b=tdApICa6c21c8X1hqbEJ7z8pr+U04k0MeGS73I1nlxn5XMAXbXXSvJI4x4tanuywSIe085yeby3ntxmhs67awc8MsKX8SsftCAYSKhc0Qj5ZsWcu07bexZn/O5vfg3VHpBGECQazzflOHnjdp1s7axfqYAKHHogs/4nR/qIRlGY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756517152; c=relaxed/simple; bh=aQfMa7G8xSMpwFrU9h8/JS2wva8i/q2sArpym3zZluI=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=A7VeXe9GCsNsBO6er9ttEc6UkradYJ+wD5/PPci51htgOimF73XGwchvJeInII0rdeHaaWp/BKDGQSlpj9kOGdhDIinPEVFA4zeO5j0dWGFKBjRfCBYHTRdRev1X/QkY5l4cXEtDTM5oLJwuqxQIEcPRsJBmBRbw9vqqBhykfd0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 172A613ACBE; Sat, 30 Aug 2025 01:25:47 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: rostedt@goodmis.org) by omf16.hostedemail.com (Postfix) with ESMTPA id E042F2000E; Sat, 30 Aug 2025 01:25:41 +0000 (UTC) Date: Fri, 29 Aug 2025 21:26:05 -0400 From: Steven Rostedt To: Linus Torvalds Cc: Arnaldo Carvalho de Melo , Steven Rostedt , linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org, Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Peter Zijlstra , Ingo Molnar , Jiri Olsa , Arnaldo Carvalho de Melo , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Jens Remus , Andrew Morton , Florian Weimer , Sam James , Kees Cook , "Carlos O'Donell" Subject: Re: [PATCH v6 5/6] tracing: Show inode and device major:minor in deferred user space stacktrace Message-ID: <20250829212605.445e1479@gandalf.local.home> In-Reply-To: <20250829212023.4ab9506f@gandalf.local.home> References: <20250828180300.591225320@kernel.org> <20250829110639.1cfc5dcc@gandalf.local.home> <20250829121900.0e79673c@gandalf.local.home> <20250829124922.6826cfe6@gandalf.local.home> <6B146FF6-B84E-40A2-A4FA-ABD5576BF463@gmail.com> <20250829141142.3ffc8111@gandalf.local.home> <20250829171855.64f2cbfc@gandalf.local.home> <20250829190935.7e014820@gandalf.local.home> <20250829212023.4ab9506f@gandalf.local.home> X-Mailer: Claws Mail 3.20.0git84 (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 X-Rspamd-Server: rspamout04 X-Rspamd-Queue-Id: E042F2000E X-Stat-Signature: p96rn3iquaawkxjothy37xu4s1xjpczj X-Session-Marker: 726F737465647440676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX1+MiEqrAYBwDRHk7XtPOHKUXUWRtT2lBTA= X-HE-Tag: 1756517141-622699 X-HE-Meta: U2FsdGVkX18XdQHVzdi5IJHrLJr+zTe1edsim9VGa7GrXpnPXGndCYwFdLFmXWnDDCkMD6Hu+g2C6VTyhqEJPVL66Oxj08WcZVP/wngTqUz66NLXCZuJ/AxtejyOt3HUXYr2WQeUh23p6pynBSTDsOOkxVGlKSCEBGj/PbddJvtn3zmUeMJ9SrkgUQqlvl++6DLMpVDNAQzS0ywOqeFFYw4mN1/DIs/AfKuDBKFi0DVJMPhmuyfmky3qUzUUBoyX8KvbzBBF2r8NU2sBSun7P2re1IbqDUFcTJrgZzbzSOlzzG9PQUcDrzoePRWAWpSsw+ZJEeBLK11Q6p6MkWHmVgoZq3RqNx2GlLupjuTdPICSB2iu/x6d8W8fhryIqMmx On Fri, 29 Aug 2025 21:20:23 -0400 Steven Rostedt wrote: > > I'm done arguing. You're not listening, so I'll just let you know that > > I am listening. I'm just not understanding you. BTW, I'm not arguing with you. I'm really trying hard to figure out what it is that you want me to do. I'm looking for that "don't use dentry outside of VFS" moment. I get we have in the call stack the offsets of the file and a magical hash value that represents that vma. What I don't get is what is user space suppose to match that magical hash value to? Do you want me to trace all mmaps and trigger an event for them that show the hash value and the path names? If that's the case, what do I do about the major use case of tracing an application after it has mapped all it's memory to files? What about wasted ring buffer space for recording every mmap when the majority of them will not be used. It could risk dropping events of the mmaps we care about. Again, I'm not arguing with you. I'm trying to figure out what you are suggesting. -- Steve