Re: [PATCH v7 0/8] selftests/cgroup: improve zswap tests robustness and support large page sizes

Andrew Morton
2026-04-24T10:06:10Z

On Fri, 24 Apr 2026 12:00:51 +0800 Li Wang <li.wang@linux.dev> wrote:

> This patchset aims to fix various spurious failures and improve the overall
> robustness of the cgroup zswap selftests.

Great, thanks, I'll queue this in mm.git's mm-new branch. Next week
I'll move it into mm-unstable, where it will receive liunx-next
exposure.

> The primary motivation is to make the tests compatible with architectures
> that use non-4K page sizes (such as 64K on ppc64le and arm64). Currently,
> the tests rely heavily on hardcoded 4K page sizes and fixed memory limits.

Well that's an oops.

> On 64K page size systems, these hardcoded values lead to sub-page granularity
> accesses, incorrect page count calculations, and insufficient memory pressure
> to trigger zswap writeback, ultimately causing the tests to fail.

I assume you've been testing on arm64 or ppc?

> Additionally, this series addresses OOM kills occurring in test_swapin_nozswap
> by dynamically scaling memory limits, and prevents spurious test failures
> when zswap is built into the kernel but globally disabled.