kernel.git/arch/arm64/kernel/ssbd.c, branch linux-4.14.yHosts the 0x221E linux distro kernel.
https://git.0xinfinity.dev/distro/kernel.git/atom?h=linux-4.14.y2019-10-29T08:17:24Zarm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL32019-10-29T08:17:24ZWill Deacon2019-10-24T12:48:18Zurn:sha1:8a235006cd422ad1c8ad1e3c2cfde1281ac52e48
[ Upstream commit 8f04e8e6e29c93421a95b61cad62e3918425eac7 ]
On CPUs with support for PSTATE.SSBS, the kernel can toggle the SSBD
state without needing to call into firmware.
This patch hooks into the existing SSBD infrastructure so that SSBS is
used on CPUs that support it, but it's all made horribly complicated by
the very real possibility of big/little systems that don't uniformly
provide the new capability.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
[ardb: add #include of asm/compat.h]
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arm64: ssbd: Add prctl interface for per-thread mitigation2018-07-22T12:28:51ZMarc Zyngier2018-07-20T09:53:08Zurn:sha1:b769d86ea9d4b2d77387791cc747462b19e8af22
commit 9cdc0108baa8ef87c76ed834619886a46bd70cbe upstream.
If running on a system that performs dynamic SSBD mitigation, allow
userspace to request the mitigation for itself. This is implemented
as a prctl call, allowing the mitigation to be enabled or disabled at
will for this particular thread.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>