Logan Gunthorpe bfeb022f8f mm/memory_hotplug: add pgprot_t to mhp_params ... devm_memremap_pages() is currently used by the PCI P2PDMA code to create struct page mappings for IO memory. At present, these mappings are created with PAGE_KERNEL which implies setting the PAT bits to be WB. However, on x86, an mtrr register will typically override this and force the cache type to be UC-. In the case firmware doesn't set this register it is effectively WB and will typically result in a machine check exception when it's accessed. Other arches are not currently likely to function correctly seeing they don't have any MTRR registers to fall back on. To solve this, provide a way to specify the pgprot value explicitly to arch_add_memory(). Of the arches that support MEMORY_HOTPLUG: x86_64, and arm64 need a simple change to pass the pgprot_t down to their respective functions which set up the page tables. For x86_32, set the page tables explicitly using _set_memory_prot() (seeing they are already mapped). For ia64, s390 and sh, reject anything but PAGE_KERNEL settings -- this should be fine, for now, seeing these architectures don't support ZONE_DEVICE. A check in __add_pages() is also added to ensure the pgprot parameter was set for all arches. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Eric Badger <ebadger@gigaio.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200306170846.9333-7-logang@deltatee.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2020-04-10 15:36:21 -07:00
..
pat	x86/mm: introduce __set_memory_prot()	2020-04-10 15:36:21 -07:00
amdtopology.c
cpu_entry_area.c
debug_pagetables.c
dump_pagetables.c
extable.c
fault.c	mm/vma: make vma_is_accessible() available for general use	2020-04-07 10:43:37 -07:00
highmem_32.c
hugetlbpage.c
ident_map.c
init_32.c	mm/memory_hotplug: add pgprot_t to mhp_params	2020-04-10 15:36:21 -07:00
init_64.c	mm/memory_hotplug: add pgprot_t to mhp_params	2020-04-10 15:36:21 -07:00
init.c	x86/mm: thread pgprot_t through init_memory_mapping()	2020-04-10 15:36:21 -07:00
iomap_32.c
ioremap.c
kasan_init_64.c
kaslr.c
kmmio.c
maccess.c
Makefile
mem_encrypt_boot.S
mem_encrypt_identity.c
mem_encrypt.c
mm_internal.h	x86/mm: thread pgprot_t through init_memory_mapping()	2020-04-10 15:36:21 -07:00
mmap.c
mmio-mod.c
numa_32.c
numa_64.c
numa_emulation.c
numa_internal.h
numa.c
pf_in.c
pf_in.h
pgtable_32.c
pgtable.c
physaddr.c
physaddr.h
pkeys.c	mm/vma: introduce VM_ACCESS_FLAGS	2020-04-10 15:36:21 -07:00
pti.c
setup_nx.c
srat.c
testmmiotrace.c
tlb.c