Commit Graph

4 Commits

Author SHA1 Message Date
Anisse Astier adeaa21a4b arm64: ssbd: explicitly depend on <linux/prctl.h>
Fix ssbd.c which depends implicitly on asm/ptrace.h including
linux/prctl.h (through for example linux/compat.h, then linux/time.h,
linux/seqlock.h, linux/spinlock.h and linux/irqflags.h), and uses
PR_SPEC* defines.

This is an issue since we'll soon be removing the include from
asm/ptrace.h.

Fixes: 9cdc0108ba ("arm64: ssbd: Add prctl interface for per-thread mitigation")
Cc: stable@vger.kernel.org
Signed-off-by: Anisse Astier <aastier@freebox.fr>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-06-17 18:38:10 +01:00
Will Deacon 8f04e8e6e2 arm64: ssbd: Add support for PSTATE.SSBS rather than trapping to EL3
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>
2018-09-14 17:46:19 +01:00
Will Deacon 2d1b2a91d5 arm64: ssbd: Drop #ifdefs for PR_SPEC_STORE_BYPASS
Now that we're all merged nicely into mainline, there's no need to check
to see if PR_SPEC_STORE_BYPASS is defined.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-14 17:46:15 +01:00
Marc Zyngier 9cdc0108ba arm64: ssbd: Add prctl interface for per-thread mitigation
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>
2018-05-31 18:00:52 +01:00