[PATCH 0/1][focal:linux] Revert "cifs: Set CIFS_MOUNT_USE_PREFIX_PATH flag on setting cifs_sb->prepath."

[Tim Gardner]

BugLink: https://bugs.launchpad.net/bugs/1923670

[Impact]

Stable updates v5.4.101 contains a2c5e4a083a7e24b35b3eb808b760af6de15bac2 (cifs:
Set CIFS_MOUNT_USE_PREFIX_PATH flag on setting cifs_sb->prepath.) which has
caused a regression for consumers of The Microsoft Distributed File System.
Upstream stable has decided to revert it in v5.4.112 for now until a root
cause is determined.

[Test Plan]

Mount a DFS share and list sub folders.

[Where problems could occur]

The intent of the original patch was to correct the output from /proc/*/*mount*.
Existing DFS consumers have obviously not encountered the bug that the patch purported
to fix, so reverting should not cause a regression.

[Other Info]

The bug report has some good discussion and diagnostics.