[PATCH 19/31] x86, pkeys: optimize fault handling in access_error()

2016-01-29 Thread Dave Hansen
From: Dave Hansen We might not strictly have to make modifictions to access_error() to check the VMA here. If we do not, we will do this: 1. app sets VMA pkey to K 2. app touches a !present page 3. do_page_fault(), allocates and maps page, sets pte.pkey=K 4. return to userspace 5. touch instruc

[PATCH 19/31] x86, pkeys: optimize fault handling in access_error()

2016-01-06 Thread Dave Hansen
From: Dave Hansen We might not strictly have to make modifictions to access_error() to check the VMA here. If we do not, we will do this: 1. app sets VMA pkey to K 2. app touches a !present page 3. do_page_fault(), allocates and maps page, sets pte.pkey=K 4. return to userspace 5. touch instruc