[v5,02/10] arm: traps: check if SMC was conditional before handling it

Commit Message

Volodymyr Babchuk Aug. 31, 2017, 8:09 p.m. UTC

Trapped SMC instruction can fail condition check on ARMv8 architecture
(ARM DDI 0487B.a page D7-2271). So we need to check if condition was meet.

Signed-off-by: Volodymyr Babchuk <[e-mail]>
Reviewed-by: Julien Grall <[e-mail]>
---

 * added Julien's R-b tag
---
xen/arch/arm/traps.c | 6 ++++++
 1 file changed, 6 insertions(+)

Patch

diff --git a/xen/arch/arm/traps.c b/xen/arch/arm/traps.c
index 4569c62..9132fe1 100644
--- a/xen/arch/arm/traps.c
+++ b/xen/arch/arm/traps.c
@@ -2159,6 +2159,12 @@  static void do_trap_smc(struct cpu_user_regs *regs, const union hsr hsr)
 {
     int rc = 0;
 
+    if ( !check_conditional_instr(regs, hsr) )
+    {
+        advance_pc(regs, hsr);
+        return;
+    }
+
     if ( current->domain->arch.monitor.privileged_call_enabled )
         rc = monitor_smc();