linux/arch
Mark Brown 92ac6fd162 arm64: Don't use KPTI where we have E0PD
Since E0PD is intended to fulfil the same role as KPTI we don't need to
use KPTI on CPUs where E0PD is available, we can rely on E0PD instead.
Change the check that forces KPTI on when KASLR is enabled to check for
E0PD before doing so, CPUs with E0PD are not expected to be affected by
meltdown so should not need to enable KPTI for other reasons.

Since E0PD is a system capability we will still enable KPTI if any of
the CPUs in the system lacks E0PD, this will rewrite any global mappings
that were established in systems where some but not all CPUs support
E0PD.  We may transiently have a mix of global and non-global mappings
while booting since we use the local CPU when deciding if KPTI will be
required prior to completing CPU enumeration but any global mappings
will be converted to non-global ones when KPTI is applied.

KPTI can still be forced on from the command line if required.

Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-01-15 14:11:17 +00:00
..
alpha alpha: use pgtable-nopud instead of 4level-fixup 2019-12-04 19:44:14 -08:00
arc treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
arm KVM/arm fixes for .5.5, take #1 2019-12-18 17:47:38 +01:00
arm64 arm64: Don't use KPTI where we have E0PD 2020-01-15 14:11:17 +00:00
c6x c6x: use pgtable-nopud instead of 4level-fixup 2019-12-04 19:44:15 -08:00
csky dma-mapping updates for 5.5-rc1 2019-11-28 11:16:43 -08:00
h8300 h8300: Move EXCEPTION_TABLE to RO_DATA segment 2019-11-04 18:12:55 +01:00
hexagon Kbuild updates for v5.5 2019-12-02 17:35:04 -08:00
ia64 drm msm + fixes for 5.5-rc1 2019-12-06 10:28:09 -08:00
m68k Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu 2019-12-05 12:20:42 -08:00
microblaze microblaze: use pgtable-nopmd instead of 4level-fixup 2019-12-04 19:44:15 -08:00
mips Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-12-22 09:54:33 -08:00
nds32 nds32: use pgtable-nopmd instead of 4level-fixup 2019-12-04 19:44:15 -08:00
nios2 nios2: Fix ioremap 2019-12-12 16:34:33 +08:00
openrisc OpenRISC updates for 5.5 2019-12-02 17:18:43 -08:00
parisc parisc: Fix compiler warnings in debug_core.c 2019-12-20 21:01:42 +01:00
powerpc PPC: 2019-12-22 10:26:59 -08:00
riscv RISC-V updates for v5.5-rc3 2019-12-22 10:22:47 -08:00
s390 s390/ftrace: save traced function caller 2019-12-18 23:29:26 +01:00
sh Wimplicit-fallthrough patches for 5.5-rc2 2019-12-14 16:10:22 -08:00
sparc treewide: Use sizeof_field() macro 2019-12-09 10:36:44 -08:00
um um: add support for folded p4d page tables 2019-12-04 19:44:15 -08:00
unicore32 generic ioremap support 2019-11-28 10:57:12 -08:00
x86 PPC: 2019-12-22 10:26:59 -08:00
xtensa arch: sembuf.h: make uapi asm/sembuf.h self-contained 2019-12-04 19:44:14 -08:00
.gitignore
Kconfig arch/Kconfig: fix indentation 2019-12-04 19:44:12 -08:00