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Date: Thu, 1 Feb 2024 07:44:31 -0800
From: Greg KH <gregkh@linuxfoundation.org>
To: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org,
	stable@vger.kernel.org
Subject: Re: [PATCH] tracing/timerlat: Move hrtimer_init to timerlat_fd open()
Message-ID: <2024020109-duffel-finally-4f0b@gregkh>
References: <7324dd3fc0035658c99b825204a66049389c56e3.1706798888.git.bristot@kernel.org>
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In-Reply-To: <7324dd3fc0035658c99b825204a66049389c56e3.1706798888.git.bristot@kernel.org>

On Thu, Feb 01, 2024 at 04:13:39PM +0100, Daniel Bristot de Oliveira wrote:
> Currently, the timerlat's hrtimer is initialized at the first read of
> timerlat_fd, and destroyed at close(). It works, but it causes an error
> if the user program open() and close() the file without reading.

What error exactly happens?  Userspace, or the kernel crashes?

thanks,

greg k-h