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Date:   Thu, 26 Nov 2020 06:52:45 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     "J. Avila" <elavila@google.com>
Cc:     rostedt@goodmis.org, mingo@redhat.com, john.stultz@linaro.org,
        linux-kernel@vger.kernel.org, kernel-team@android.com
Subject: Re: Potential Issue in Tracing Ring Buffer
Message-ID: <X79CrSX1rnpnbqPd@kroah.com>
References: <20201124223917.795844-1-elavila@google.com>
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On Tue, Nov 24, 2020 at 10:39:17PM +0000, J. Avila wrote:
> Hello,
> 
> In the ftrace logs we've collected internally, we have found that there are
> situations where time seems to go backwards; this breaks userspace tools which
> expect time to always go forward in these logs. For example, in this snippet
> from a db845c running a 5.10-rc4 kernel[1] (thanks for getting us the trace,
> John!), we see:

Does the patch at:
	https://lore.kernel.org/r/20201125225654.1618966-1-minchan@kernel.org

resolve this issue for you?

thanks,

greg kh-