arm64: trap userspace "dc cvau" cache operation on errata-affected core
The ARM errata 819472, 826319, 827319 and 824069 for affected
Cortex-A53 cores demand to promote "dc cvau" instructions to
"dc civac". Since we allow userspace to also emit those instructions,
we should make sure that "dc cvau" gets promoted there too.
So lets grasp the nettle here and actually trap every userland cache
maintenance instruction once we detect at least one affected core in
the system.
We then emulate the instruction by executing it on behalf of userland,
promoting "dc cvau" to "dc civac" on the way and injecting access
fault back into userspace.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
[catalin.marinas@arm.com: s/set_segfault/arm64_notify_segfault/]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 751e901..cc06794 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -98,11 +98,11 @@
SCTLR_ELx_SA | SCTLR_ELx_I)
/* SCTLR_EL1 specific flags. */
+#define SCTLR_EL1_UCI (1 << 26)
#define SCTLR_EL1_SPAN (1 << 23)
#define SCTLR_EL1_SED (1 << 8)
#define SCTLR_EL1_CP15BEN (1 << 5)
-
/* id_aa64isar0 */
#define ID_AA64ISAR0_RDM_SHIFT 28
#define ID_AA64ISAR0_ATOMICS_SHIFT 20