i386: split svm_helper into sysemu and stub-only user

For now we just copy over the previous user stubs, but really,

everything that requires s->cpl == 0 should be impossible
to trigger from user-mode emulation.

Later on we should add a check that asserts this easily f.e.:

static bool check_cpl0(DisasContext *s)
{
     int cpl = s->cpl;
 #ifdef CONFIG_USER_ONLY
     assert(cpl == 3);
 #endif
     if (cpl != 0) {
         gen_exception(s, EXCP0D_GPF, s->pc_start - s->cs_base);
         return false;
     }
     return true;
}

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210322132800.7470-17-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

2 files changed, 77 insertions, 0 deletions

diff --git a/target/i386/tcg/user/meson.build b/target/i386/tcg/user/meson.build
index 2ab8bd903c..3edaee7402 100644
--- a/target/i386/tcg/user/meson.build
+++ b/target/i386/tcg/user/meson.build
@@ -1,4 +1,5 @@
 i386_user_ss.add(when: ['CONFIG_TCG', 'CONFIG_USER_ONLY'], if_true: files(
   'excp_helper.c',
   'misc_stubs.c',
+  'svm_stubs.c',
 ))
diff --git a/target/i386/tcg/user/svm_stubs.c b/target/i386/tcg/user/svm_stubs.c
new file mode 100644
index 0000000000..97528b56ad
--- /dev/null
+++ b/target/i386/tcg/user/svm_stubs.c
@@ -0,0 +1,76 @@
+/*
+ *  x86 SVM helpers (user-mode)
+ *
+ *  Copyright (c) 2003 Fabrice Bellard
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "exec/helper-proto.h"
+#include "tcg/helper-tcg.h"
+
+void helper_vmrun(CPUX86State *env, int aflag, int next_eip_addend)
+{
+}
+
+void helper_vmmcall(CPUX86State *env)
+{
+}
+
+void helper_vmload(CPUX86State *env, int aflag)
+{
+}
+
+void helper_vmsave(CPUX86State *env, int aflag)
+{
+}
+
+void helper_stgi(CPUX86State *env)
+{
+}
+
+void helper_clgi(CPUX86State *env)
+{
+}
+
+void helper_skinit(CPUX86State *env)
+{
+}
+
+void helper_invlpga(CPUX86State *env, int aflag)
+{
+}
+
+void cpu_vmexit(CPUX86State *nenv, uint32_t exit_code, uint64_t exit_info_1,
+                uintptr_t retaddr)
+{
+    assert(0);
+}
+
+void helper_svm_check_intercept_param(CPUX86State *env, uint32_t type,
+                                      uint64_t param)
+{
+}
+
+void cpu_svm_check_intercept_param(CPUX86State *env, uint32_t type,
+                                   uint64_t param, uintptr_t retaddr)
+{
+}
+
+void helper_svm_check_io(CPUX86State *env, uint32_t port, uint32_t param,
+                         uint32_t next_eip_addend)
+{
+}