arm64: fix erroneous __raw_read_system_reg() cases
authorMark Rutland <mark.rutland@arm.com>
Thu, 2 Feb 2017 17:32:14 +0000 (17:32 +0000)
committerWill Deacon <will.deacon@arm.com>
Thu, 2 Feb 2017 18:34:38 +0000 (18:34 +0000)
commit7d0928f18bf890d2853281f59aba0dd5a46b34f9
treee2fbef6264e8608440f16922cc497933393495cf
parentf85279b4bd481a1a0697c1d2a8a5f15de216b120
arm64: fix erroneous __raw_read_system_reg() cases

Since it was introduced in commit da8d02d19ffdd201 ("arm64/capabilities:
Make use of system wide safe value"), __raw_read_system_reg() has
erroneously mapped some sysreg IDs to other registers.

For the fields in ID_ISAR5_EL1, our local feature detection will be
erroneous. We may spuriously detect that a feature is uniformly
supported, or may fail to detect when it actually is, meaning some
compat hwcaps may be erroneous (or not enforced upon hotplug).

This patch corrects the erroneous entries.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Fixes: da8d02d19ffdd201 ("arm64/capabilities: Make use of system wide safe value")
Reported-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm64/kernel/cpufeature.c