Re: [PATCH] x86/mm/32: Bring back vmalloc faulting on x86_32

[Joerg Roedel]

Hi Andy,

On Thu, Sep 03, 2020 at 07:52:35AM -0700, Andy Lutomirski wrote:
> Does this mean we can get rid of arch_sync_kernel_mappings()?  Or
> should we consider adding some locking to make it non-racy again?

Well, removing arch_sync_kernel_mappings() would mean to re-introduce
vmalloc_sync_all() calls all over the place, I am not in favour for
that.

I also thought about locking, but that is not easily doable without
destroying performance/scalability of the vmalloc alloc/free path for
other architectures too. It _could_ be done, but the effort is large and
touches a lot of generic page-table allocation code just for x86-32.
This seemed not worth it while thinking about it.

Regards,

	Joerg