Comment 14 for bug 2048945

Overview:

Several users report that after upgrading from 6.4.12 to 6.5 the process scsi_eh_1 will constantly consume >10% CPU resources. This happens most often in VMs.

Steps to Reproduce:

- Create a VM (e.g. VMware Fusion)
- Create an SCSI disk
- Connect a virtual CD ROM (IDE)
- Boot a 6.4.12 kernel
- Boot a 6.5 kernel

Actual Results:

- no issues for the 6.4.12 kernel
- scsi_eh consumes too much CPU with the 6.5 kernel

Expected Results:

scsi_eh should not consume significant resources.

Build Date & Hardware:

Linux arch 6.5.2-arch1-1 #1 SMP PREEMPT_DYNAMIC Wed, 06 Sep 2023 21:01:01 +0000 x86_64 GNU/Linux
inside a VMware Fusion VM

Additional Builds and Platforms:

Other users were able to reproduce the error on bare metal hardware.

Additional Information:

More details can be found in this thread:
https://bbs.archlinux.org/viewtopic.php?id=288723

The users loqs and leonshaw helped to narrow it down to this commit:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=624885209f31eb9985bf51abe204ecbffe2fdeea

good: 6.4.0-rc1-1-00007-g152e52fb6ff1
bad: 6.4.0-rc1-1-00008-g624885209f31