2cf3f8133b
Commit ccaa66c8dd27 reinstated the kmap/kunmap that had been dropped in
commit 8c945d32e604 ("btrfs: compression: drop kmap/kunmap from lzo").
However, it seems to have done so incorrectly due to the change not
reverting cleanly, and lzo_decompress_bio() ended up not having a
matching "kunmap()" to the "kmap()" that was put back.
Also, any assert that the page pointer is not NULL should be before the
kmap() of said pointer, since otherwise you'd just oops in the kmap()
before the assert would even trigger.
I noticed this when trying to verify my btrfs merge, and things not
adding up. I'm doing this fixup before re-doing my merge, because this
commit needs to also be backported to 5.15 (after verification from the
btrfs people).
Fixes: ccaa66c8dd27 ("Revert 'btrfs: compression: drop kmap/kunmap from lzo'")
Cc: David Sterba <dsterba@suse.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.