On Tue, Dec 17, 2024 at 09:23:07AM +0100, Thomas Bogendoerfer wrote: > On Thu, Dec 12, 2024 at 03:36:45PM +0000, Lorenzo Stoakes wrote: > > Currently the only user of mmap_region() outside of the memory management > > code is the MIPS VDSO implementation. > > > > This uses mmap_region() to map a 'delay slot emulation page' at the top of > > the stack which is read-only and executable. > > > > This mapping requires that an already-acquired mmap write lock is utilised > > and that uffd and populate logic is ignored. This rules out vm_mmap(), > > however do_mmap() fits the bill. > > > > Adapt this code to use do_mmap() and then once done, make mmap_region() > > internal and userland testable, and avoid any other uses of mmap_region(), > > which is absolutely and strictly an internal mm function which bypasses a > > great number of checks and logic. > > > > REVIEWERS NOTES: > > > > Thomas - I lack the hardware or set up to test this beyond a simple > > cross-compilation test, so I need some input from you MIPS guys as to > > whether this is workable. > > > > I've therefore sent this as an RFC so we can be sure this is suitable! > > Please could you check to make sure this change is OK and I haven't missed > > anything? > > conversation looks correct, but this patch doesn't apply to upstream v6.13-rc1. > Which tree are you using ? Thanks, yeah mm-unstable as Liam points out but clearly not the tip one :) Let me rebase and resend. Thanks! > > Thomas. > > -- > Crap can work. Given enough thrust pigs will fly, but it's not necessarily a > good idea. [ RFC1925, 2.3 ] >
