Re: [iproute PATCH] tc: u32: Fix key folding in sample option

Hi,

On Tue, Feb 02, 2021 at 07:30:51PM +0100, Phil Sutter wrote:

In between Linux kernel 2.4 and 2.6, key folding for hash tables changed
in kernel space. When iproute2 dropped support for the older algorithm,
the wrong code was removed and kernel 2.4 folding method remained in
place. To get things functional for recent kernels again, restoring the
old code alone was not sufficient - additional byteorder fixes were
needed.

While being at it, make use of ffs() and thereby align the code with how
kernel determines the shift width.

Fixes: 267480f55383c ("Backout the 2.4 utsname hash patch.")
Signed-off-by: Phil Sutter <phil@nwl.cc>

Seems this patch fell off the table? Or was there an objection I missed?

FWIW, the related kernel selftests patch[1] which asserts this patch's
change is upstream already.

Cheers, Phil

[1] 373e13bc63639 ("selftests: tc-testing: u32: Add tests covering
sample option")