linux/arch/powerpc
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
..
boot powerpc updates for 5.7 2020-04-05 11:12:59 -07:00
configs powerpc updates for 5.7 #2 2020-04-09 11:01:42 -07:00
crypto crypto: remove CRYPTO_TFM_RES_BAD_KEY_LEN 2020-01-09 11:30:53 +08:00
include powerpc/mm: thread pgprot_t through create_section_mapping() 2020-04-10 15:36:21 -07:00
kernel powerpc updates for 5.7 #2 2020-04-09 11:01:42 -07:00
kexec powerpc updates for 5.7 2020-04-05 11:12:59 -07:00
kvm virtio: fixes, vdpa 2020-04-08 10:51:53 -07:00
lib powerpc/64/sstep: Ifdef the deprecated fast endian switch syscall 2020-04-01 13:42:13 +11:00
math-emu
mm mm/memory_hotplug: add pgprot_t to mhp_params 2020-04-10 15:36:21 -07:00
net treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
oprofile powerpc updates for 5.6 2020-02-04 13:06:46 +00:00
perf powerpc updates for 5.7 #2 2020-04-09 11:01:42 -07:00
platforms powerpc updates for 5.7 #2 2020-04-09 11:01:42 -07:00
purgatory .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
sysdev powerpc/xive: Add a debugfs file to dump internal XIVE state 2020-03-27 00:20:38 +11:00
tools powerpc: Do not consider weak unresolved symbol relocations as bad 2020-01-31 20:17:22 +11:00
xmon powerpc: Make setjmp/longjmp signature standard 2020-04-01 14:30:51 +11:00
Kbuild powerpc/kexec: Move kexec files into a dedicated subdir. 2019-11-21 15:41:34 +11:00
Kconfig powerpc updates for 5.7 #2 2020-04-09 11:01:42 -07:00
Kconfig.debug powerpc/ptdump: Only enable PPC_CHECK_WX with STRICT_KERNEL_RWX 2020-01-23 21:31:13 +11:00
Makefile powerpc: Suppress .eh_frame generation 2020-04-01 14:30:51 +11:00
Makefile.postlink powerpc: Do not consider weak unresolved symbol relocations as bad 2020-01-31 20:17:22 +11:00