Re: [PATCH 5.8 574/633] selftests/bpf: Fix overflow tests to reflect iter size increase

From: Alan Maguire
Date: Tue Oct 27 2020 - 12:39:01 EST


On Tue, 27 Oct 2020, Greg Kroah-Hartman wrote:

> From: Alan Maguire <alan.maguire@xxxxxxxxxx>
>
> [ Upstream commit eb58bbf2e5c7917aa30bf8818761f26bbeeb2290 ]
>
> bpf iter size increase to PAGE_SIZE << 3 means overflow tests assuming
> page size need to be bumped also.
>

Alexei can correct me if I've got this wrong but I don't believe
it's a stable backport candidate.

This selftests change should only be relevant when the BPF iterator
size has been bumped up as it was in

af65320 bpf: Bump iter seq size to support BTF representation of large
data structures

...so I don't _think_ this commit belongs in stable unless the
above commit is backported also (and unless I'm missing something
I don't see a burning reason to do that currently).

Backporting this alone will likely induce bpf test failures.
Apologies if the "Fix" in the title was misleading; it should
probably have been "Update" to reflect the fact it's not fixing
an existing bug but rather updating the test to operate correctly
in the context of other changes in the for-next patch series
it was part of.

Thanks!

Alan