On Thu, Feb 10, 2022 at 09:35:10PM +1100, Alistair Popple wrote: > I got the following build error: > > /data/source/linux/mm/migrate_device.c: In function ‘migrate_vma_collect_pmd’: > /data/source/linux/mm/migrate_device.c:242:3: error: implicit declaration of function ‘flush_tlb_range’; did you mean ‘flush_pmd_tlb_range’? [-Werror=implicit-function-declaration] > 242 | flush_tlb_range(walk->vma, start, end); > | ^~~~~~~~~~~~~~~ > | flush_pmd_tlb_range > > Including asm/tlbflush.h in migrate_device.c fixed it for me. Yes, the buildbot also complained about this, but somehow in my test configfs it got pulled in implicitly.