On Tue, Dec 22, 2020 at 7:01 PM Andreas Larsson <andreas@xxxxxxxxxxx> wrote: > > Unfortunately I did not see this problem before I encountered it in > master. Commit 3293efa9780712ad8504689e0c296d2bd33827d5 > ... > > I will have to continue to dig deeper into this in January. If anyone > has any ideas how this could stem from this kmap patch, I am all ears. I don't immediately see it, but an easy thing to try would be to disable CONFIG_HIGHMEM. I don't know what the limits are on sparc, but you can often change the virtual address layout to reserve enough space for mapping all of the physical memory, as e.g. CONFIG_VMSPLIT_2G does on x86 or arm. There is also some discussion about eventually removing highmem support from the kernel entirely. Arnd