Re: [PATCH v2] x86/mm: Drop 4MB restriction on minimal NUMA node memory size

From: Ingo Molnar
Date: Wed Oct 18 2023 - 08:45:02 EST



* Qi Zheng <zhengqi.arch@xxxxxxxxxxxxx> wrote:

> > While I agree with dropping the limitation, and I agree that
> > 9391a3f9c7f1 should have provided more of a justification, I believe a
> > core MM fix is in order as well, for it to not crash. [ If it's fixed
> > upstream already, please reference the relevant commit ID. ]
>
> Agree. I posted a fixed patchset[1] before, maybe we can reconsider it.
> :)
>
> [1]. https://lore.kernel.org/lkml/20230215152412.13368-1-zhengqi.arch@xxxxxxxxxxxxx/
>
> For memoryless node, this patchset skip it and fallback to other nodes
> when build its zonelists.

Mind resubmitting that to the MM folks, with the NULL dereference crash
mentioned prominently? Feel free to Cc: me.

Fixing hypothetical robustness problems is good, fixing specific crashes is
better. :-)

Thanks,

Ingo