arm64: Force KPTI to be disabled on Cavium ThunderX
authorMarc Zyngier <marc.zyngier@arm.com>
Mon, 29 Jan 2018 11:59:56 +0000 (11:59 +0000)
committerCatalin Marinas <catalin.marinas@arm.com>
Tue, 6 Feb 2018 22:53:20 +0000 (22:53 +0000)
commit6dc52b15c4a48052ade2529d639eee401d76e469
treed17838e0b7e96b777a1adfc6902d42d92971e31f
parentf992b4dfd58be07e31a42bc940a53b3e4b282616
arm64: Force KPTI to be disabled on Cavium ThunderX

Cavium ThunderX's erratum 27456 results in a corruption of icache
entries that are loaded from memory that is mapped as non-global
(i.e. ASID-tagged).

As KPTI is based on memory being mapped non-global, let's prevent
it from kicking in if this erratum is detected.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
[will: Update comment]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
arch/arm64/kernel/cpufeature.c