Quoting Andrew Morton (2020-08-21 23:34:12)
On Fri, 21 Aug 2020 14:37:46 +0200 Joerg Roedel joro@8bytes.org wrote:
The __apply_to_page_range() function is also used to change and/or allocate page-table pages in the vmalloc area of the address space. Make sure these changes get synchronized to other page-tables in the system by calling arch_sync_kernel_mappings() when necessary.
Tested-by: Chris Wilson chris@chris-wilson.co.uk #x86-32 Cc: stable@vger.kernel.org # v5.8+
I'm trying to figure out how you figured out that this is 5.8+. Has a particular misbehaving commit been identified?
The two commits of relevance, in my eyes, were
2ba3e6947aed ("mm/vmalloc: track which page-table levels were modified") 86cf69f1d893 ("x86/mm/32: implement arch_sync_kernel_mappings()")
I can reproduce the failure on v5.8, but not on v5.7. A bisect would seem to be plausible. -Chris