[PULL,19/38] target/ricsv: Flush the TLB on virtulisation mode changes

Commit Message

Palmer Dabbelt March 3, 2020, 12:48 a.m. UTC

From: Alistair Francis <[e-mail]>

To ensure our TLB isn't out-of-date we flush it on all virt mode
changes. Unlike priv mode this isn't saved in the mmu_idx as all
guests share V=1. The easiest option is just to flush on all changes.

Signed-off-by: Alistair Francis <[e-mail]>
Reviewed-by: Palmer Dabbelt <[e-mail]>
Signed-off-by: Palmer Dabbelt <[e-mail]>
---
 target/riscv/cpu_helper.c | 5 +++++
 1 file changed, 5 insertions(+)

Patch

diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c
index ccf67aca05..a8b114ae16 100644
--- a/target/riscv/cpu_helper.c
+++ b/target/riscv/cpu_helper.c
@@ -181,6 +181,11 @@  void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable)
         return;
     }
 
+    /* Flush the TLB on all virt mode changes. */
+    if (get_field(env->virt, VIRT_ONOFF) != enable) {
+        tlb_flush(env_cpu(env));
+    }
+
     env->virt = set_field(env->virt, VIRT_ONOFF, enable);
 }