[Xen-devel] [PATCH] arm/monitor: flush the icache during SMC traps

[Tamas K Lengyel <tamas.lengyel@xxxxxxxxxxxx>]

During an SMC trap it is possible that the user may change the memory
from where the SMC was fetched. However, without flushing the icache
the SMC may still trigger if the pCPU was idle during the trap. Flush
the icache to ensure consistency.

Signed-off-by: Tamas K Lengyel <tamas.lengyel@xxxxxxxxxxxx>
---
Cc: Razvan Cojocaru <rcojocaru@xxxxxxxxxxxxxxx>
Cc: Stefano Stabellini <sstabellini@xxxxxxxxxx>
Cc: Julien Grall <julien.grall@xxxxxxx>
---
 xen/arch/arm/monitor.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/xen/arch/arm/monitor.c b/xen/arch/arm/monitor.c
index 59ce8f635f..ae1b97993f 100644
--- a/xen/arch/arm/monitor.c
+++ b/xen/arch/arm/monitor.c
@@ -63,6 +63,9 @@ int monitor_smc(void)
         .reason = VM_EVENT_REASON_PRIVILEGED_CALL
     };
 
+    /* Nuke the icache as the memory may get changed underneath us. */
+    invalidate_icache();
+
     return monitor_traps(current, 1, &req);
 }
 
-- 
2.11.0


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel