Re: [Crash-utility] [PATCH v1] arm64: fix kernel memory map handling for kaslr-enabled

----- Original Message ----- > On Tue, May 24, 2016 at 09:35:54AM -0400, Dave Anderson wrote: > > > > > > ----- Original Message ----- > > > > > > > > > > Now that PHYS_OFFSET is defined as "memstart_addr", we can get the value > > > > > if we can access this symbol (on a live system). > > > > > > > > When PHYS_OFFSET/memstart_addr is bumped up from the actual base of physical > > > > memory, is the physical memory below it no longer used/accessible? > > > > > > Yes, it is! That is what Ard has managed to do in his series of > > > KASLR-related patches. > > > > How is it accessed via a kernel virtual address? Or is only accessible when > > mapped into a vmalloc() or user-space address? > > Through a linear(unity) mapping above PAGE_OFFSET. I'm still confused... Does PAGE_OFFSET+0 still refer to PHYS_OFFSET?

I'm trying to wrap my head around how __virt_to_phys() would work for the memory below the bumped-up PHYS_OFFSET. Dave -- Crash-utility mailing list Crash-utility(a)redhat.com https://www.redhat.com/mailman/listinfo/crash-utility