On Mon, 13 Nov 2017 10:29:19 +0530 "Aneesh Kumar K.V" <aneesh.ku...@linux.vnet.ibm.com> wrote:
> Nicholas Piggin <npig...@gmail.com> writes: > > > When allocating VA space with a hint that crosses 128TB, the SLB addr_limit > > variable is not expanded if addr is not > 128TB, but the slice allocation > > looks at task_size, which is 512TB. This results in slice_check_fit() > > incorrectly succeeding because the slice_count truncates off bit 128 of the > > requested mask, so the comparison to the available mask succeeds. > > > > Fix this by using mm->context.addr_limit instead of mm->task_size for > > testing allocation limits. This causes such allocations to fail. > > > > Also note that this change the rule from > 128TB to >-128TB to select > the larger address space. I guess that is correct because without '>=' we > won't be able to allocate anything starting from 128TB (except MAP_FIXED). Oh yes, thanks. That should at least be in the changelog. Probably split into its own patch really. Thanks, Nick
