Commits
Marc Zyngier committed 71d65a3fc62
arm64: Introduce a way to disable the 32bit vdso commit 97884ca8c2925d14c32188e865069f21378b4b4f upstream. [this is a redesign rather than a backport] We have a class of errata (grouped under the ARM64_WORKAROUND_1418040 banner) that force the trapping of counter access from 32bit EL0. We would normally disable the whole vdso for such defect, except that it would disable it for 64bit userspace as well, which is a shame. Instead, add a new vdso_clock_mode, which signals that the vdso isn't usable for compat tasks. This gets checked in the new vdso_clocksource_ok() helper, now provided for the 32bit vdso. Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200706163802.1836732-2-maz@kernel.org Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>