x86/module: Fix the paravirt vs alternative order

commit 5adf349439d29f92467e864f728dfc23180f3ef9 upstream.

Ever since commit

  4e6292114c74 ("x86/paravirt: Add new features for paravirt patching")

there is an ordering dependency between patching paravirt ops and
patching alternatives, the module loader still violates this.

Fixes: 4e6292114c74 ("x86/paravirt: Add new features for paravirt patching")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220303112825.068773913@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 867a341a0c7e84cbad83b7f2ec286f86a50c88b0..32e546e41629637a86e90e71d749e629b93095a4 100644 (file)
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -270,6 +270,14 @@ int module_finalize(const Elf_Ehdr *hdr,
                        orc_ip = s;
        }
 
+       /*
+        * See alternative_instructions() for the ordering rules between the
+        * various patching types.
+        */
+       if (para) {
+               void *pseg = (void *)para->sh_addr;
+               apply_paravirt(pseg, pseg + para->sh_size);
+       }
        if (alt) {
                /* patch .altinstructions */
                void *aseg = (void *)alt->sh_addr;
@@ -283,11 +291,6 @@ int module_finalize(const Elf_Ehdr *hdr,
                                            tseg, tseg + text->sh_size);
        }
 
-       if (para) {
-               void *pseg = (void *)para->sh_addr;
-               apply_paravirt(pseg, pseg + para->sh_size);
-       }
-
        /* make jump label nops */
        jump_label_apply_nops(me);