[PATCH v2 0/6] mm: Stop alaising VM_FAULT_HINDEX_MASK in arch code

[Palmer Dabbelt]

When reviewing
<https://lore.kernel.org/r/20221029084715.3669204-1-tongtiangen@huawei.com>
I noticed that the arch-specific VM_FAULT flags used by arm and s390
alias with VM_FAULT_HINDEX_MASK.  I'm not sure if it's possible to
manifest this as a bug, but it certainly seems fragile.

I'm including that original patch this time in the hope that makes it
easier for folks to review.  There were some boring conflicts so I
figured I'd rebase rather than pinging again.

Changes since v1 <20221203030356.3917-1-palmer at rivosinc.com>:

* Add the original patch, and reorder the RISC-V stuff first.
* Rebased on v6.3-rc2
* Moved the comment about VM_FAULT_ARCH_* to the patch that adds those,
  rather than the patch that adds 0s.