On 19.03.23 01:15, Rick Edgecombe wrote:
From: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx> The x86 Control-flow Enforcement Technology (CET) feature includes a new type of memory called shadow stack. This shadow stack memory has some unusual properties, which requires some core mm changes to function properly. Future patches will introduce a new VM flag VM_SHADOW_STACK that will be VM_HIGH_ARCH_BIT_5. VM_HIGH_ARCH_BIT_1 through VM_HIGH_ARCH_BIT_4 are bits 32-36, and bit 37 is the unrelated VM_UFFD_MINOR_BIT. For the sake of order, make all VM_HIGH_ARCH_BITs stay together by moving VM_UFFD_MINOR_BIT from 37 to 38. This will allow VM_SHADOW_STACK to be introduced as 37. Co-developed-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx> Signed-off-by: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx> Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> Reviewed-by: Axel Rasmussen <axelrasmussen@xxxxxxxxxx> Acked-by: Mike Rapoport (IBM) <rppt@xxxxxxxxxx> Acked-by: Peter Xu <peterx@xxxxxxxxxx> Tested-by: Pengfei Xu <pengfei.xu@xxxxxxxxx> Tested-by: John Allen <john.allen@xxxxxxx> Tested-by: Kees Cook <keescook@xxxxxxxxxxxx> ---
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> -- Thanks, David / dhildenb