Re: [PATCH -next] panic: complete the flush of the hard deadlock log messages to the serial port

From: xuqiang (M)
Date: Tue Dec 08 2020 - 03:35:40 EST



在 2020/11/24 11:22, xuqiang (M) 写道:

在 2020/11/24 3:52, Andrew Morton 写道:
On Mon, 23 Nov 2020 13:13:59 +0000 Xu Qiang <xuqiang36@xxxxxxxxxx> wrote:

when hardlockup_all_cpu_backtrace is on, and there are
a large number of cores in the system, it takes
a long time to output the hard deadlock logs of all cores
to the serial port. When the console_flush_on_panic function
in panic is executed, console_locked is still held.
As a result, garbled characters are displayed in the serial port log.

To solve this problem, wait for a maximum of 10s for the serial port
to be released before console_flush_on_panic.
Wouldn't it be better to wait until all the printing of all those
backtraces has completed?


.

The fear that there may be some unexpected abnormal situation,

resulting in the serial port has been occupied without release.


Thanks

        Xu.

Hi, Are there any other questions about this patch?


Thanks

        Xu.