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Date:   Fri, 11 Feb 2022 12:09:38 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc:     johannes@sipsolutions.net, linux-kernel@vger.kernel.org,
        rafael@kernel.org, robdclark@gmail.com,
        dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org,
        freedreno@lists.freedesktop.org, seanpaul@chromium.org,
        swboyd@chromium.org, nganji@codeaurora.org,
        aravindh@codeaurora.org, khsieh@codeaurora.org, daniel@ffwll.ch,
        dmitry.baryshkov@linaro.org
Subject: Re: [PATCH] devcoredump: increase the device delete timeout to 10
 mins
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On Tue, Feb 08, 2022 at 11:44:32AM -0800, Abhinav Kumar wrote:
> There are cases where depending on the size of the devcoredump and the speed
> at which the usermode reads the dump, it can take longer than the current 5 mins
> timeout.
> 
> This can lead to incomplete dumps as the device is deleted once the timeout expires.
> 
> One example is below where it took 6 mins for the devcoredump to be completely read.
> 
> 04:22:24.668 23916 23994 I HWDeviceDRM::DumpDebugData: Opening /sys/class/devcoredump/devcd6/data
> 04:28:35.377 23916 23994 W HWDeviceDRM::DumpDebugData: Freeing devcoredump node

What makes this so slow?  Reading from the kernel shouldn't be the
limit, is it where the data is being sent to?

> Increase the timeout to 10 mins to accommodate system delays and large coredump
> sizes.

Nit, please wrap your changelog texts at 72 columns.

And what is "large"?

thanks,

greg k-h