[Qemu-devel] [PATCH] target-arm: correctly UNDEF writes to FPINST/FPINST2 from EL0

[Peter Maydell]

The ARM ARM requires that the FPINST and FPINST2 VFP control
registers are not accessible to code at EL0. We were already
correctly implementing this for reads of these registers; add
the missing check for the write code path.

Signed-off-by: Peter Maydell <address@hidden>
---
 target-arm/translate.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/target-arm/translate.c b/target-arm/translate.c
index 8a2994f..d8ee2e4 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -3199,6 +3199,9 @@ static int disas_vfp_insn(CPUARMState * env, DisasContext 
*s, uint32_t insn)
                             break;
                         case ARM_VFP_FPINST:
                         case ARM_VFP_FPINST2:
+                            if (IS_USER(s)) {
+                                return 1;
+                            }
                             tmp = load_reg(s, rd);
                             store_cpu_field(tmp, vfp.xregs[rn]);
                             break;
-- 
1.9.1