commit 66c6b40aba13807506f20c7522f4930c9ffc76ce
author Matheus Ferst <matheus.ferst@eldorado.org.br> Thu Oct 14 19:32:31 2021 -0300
committer David Gibson <david@gibson.dropbear.id.au> Thu Oct 21 11:42:47 2021 +1100
tree d1658e09ad6da6d61eebcbe4c2a323bf4fcf2c68
parent 252fcf36bba483493365e91c2f98569de29a43fd

linux-user/ppc: Fix XER access in save/restore_user_regs

We should use cpu_read_xer/cpu_write_xer to save/restore the complete
register since some of its bits are in other fields of CPUPPCState. A
test is added to prevent future regressions.

Fixes: da91a00f191f ("target-ppc: Split out SO, OV, CA fields from XER")
Signed-off-by: Matheus Ferst <matheus.ferst@eldorado.org.br>
Message-Id: <20211014223234.127012-2-matheus.ferst@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

linux-user/ppc/signal.c

diff --git a/linux-user/ppc/signal.c b/linux-user/ppc/signal.c
index c37744c..90a0369 100644
--- a/linux-user/ppc/signal.c
+++ b/linux-user/ppc/signal.c
@@ -242,7 +242,7 @@
     __put_user(env->nip, &frame->mc_gregs[TARGET_PT_NIP]);
     __put_user(env->ctr, &frame->mc_gregs[TARGET_PT_CTR]);
     __put_user(env->lr, &frame->mc_gregs[TARGET_PT_LNK]);
-    __put_user(env->xer, &frame->mc_gregs[TARGET_PT_XER]);
+    __put_user(cpu_read_xer(env), &frame->mc_gregs[TARGET_PT_XER]);
 
     for (i = 0; i < ARRAY_SIZE(env->crf); i++) {
         ccr |= env->crf[i] << (32 - ((i + 1) * 4));
@@ -315,6 +315,7 @@
 {
     target_ulong save_r2 = 0;
     target_ulong msr;
+    target_ulong xer;
     target_ulong ccr;
 
     int i;
@@ -330,9 +331,11 @@
     __get_user(env->nip, &frame->mc_gregs[TARGET_PT_NIP]);
     __get_user(env->ctr, &frame->mc_gregs[TARGET_PT_CTR]);
     __get_user(env->lr, &frame->mc_gregs[TARGET_PT_LNK]);
-    __get_user(env->xer, &frame->mc_gregs[TARGET_PT_XER]);
-    __get_user(ccr, &frame->mc_gregs[TARGET_PT_CCR]);
 
+    __get_user(xer, &frame->mc_gregs[TARGET_PT_XER]);
+    cpu_write_xer(env, xer);
+
+    __get_user(ccr, &frame->mc_gregs[TARGET_PT_CCR]);
     for (i = 0; i < ARRAY_SIZE(env->crf); i++) {
         env->crf[i] = (ccr >> (32 - ((i + 1) * 4))) & 0xf;
     }