From mboxrd@z Thu Jan  1 00:00:00 1970
From: Lakshmi Narasimhan Sundararajan <lsundararajan@purestorage.com>
Date: Wed, 10 Nov 2021 18:41:40 +0530
Subject: Need clarification
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Hi LVM Team!
A very good day to you.

I have the following observation, and I need your inputs to understand behavior.

1/ create a volume group on a single block device.
2/ create a logical volume on the volume group.
3/ pump IO to the dm device
4/ while IOs are active, force kernel crash through the sysrq interface.

This results in a kernel hang. possibly because of IOs waiting to be
serviced still.
This behavior is seen over thin pool, thin device as well.

1/ Is this behavior known or understood well as to why the kernel does
not complete a shutdown?
2/ Is there any configuration with the lvm/dm layer that can allow the
kernel to proceed to complete shutdown and reboot failing those
incomplete IOs?

Please advise.

Thanks
LN