On 2/8/24 18:36, Alexei Starovoitov wrote:
I'm inclined to tackle wrap32 issue differently and simply
disallow [user_vm_start, user_vm_end] combination
where lower 32-bit can wrap.
In other words it would mean that mmap() of len=4Gb will be
aligned to 4Gb,
while mmap() of len=1M will be offsetted in such a way
that both addr and add+1M have the same upper 32-bit.
(It's not the same as 1M aligned).
With that I will remove vmap_pages_range_wrap32() and
do single normal vmap_pages_range() without extra tricks.
wdyt?
SGTM.
knowing that you can't wrap the lower 32 removes a lot of headaches.
and the restriction of aligning a 4GB mapping to 4GB boundary is pretty
sane. TBH doing it elsewhere is just asking for heartache. =)
barret
