Merge tag 'for-5.15/parisc' of git://git.kernel.org/pub/scm/linux/kernel/git/deller...

[linux-2.6-microblaze.git] / arch / s390 / kernel / module.c

diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
index 4055f1c..b01ba46 100644 (file)
--- a/arch/s390/kernel/module.c
+++ b/arch/s390/kernel/module.c
@@ -14,6 +14,7 @@
 #include <linux/elf.h>
 #include <linux/vmalloc.h>
 #include <linux/fs.h>
+#include <linux/ftrace.h>
 #include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/kasan.h>
@@ -23,6 +24,8 @@
 #include <asm/alternative.h>
 #include <asm/nospec-branch.h>
 #include <asm/facility.h>
+#include <asm/ftrace.lds.h>
+#include <asm/set_memory.h>
 
 #if 0
 #define DEBUGP printk
@@ -48,6 +51,13 @@ void *module_alloc(unsigned long size)
        return p;
 }
 
+#ifdef CONFIG_FUNCTION_TRACER
+void module_arch_cleanup(struct module *mod)
+{
+       module_memfree(mod->arch.trampolines_start);
+}
+#endif
+
 void module_arch_freeing_init(struct module *mod)
 {
        if (is_livepatch_module(mod) &&
@@ -466,6 +476,30 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
                                    write);
 }
 
+#ifdef CONFIG_FUNCTION_TRACER
+static int module_alloc_ftrace_hotpatch_trampolines(struct module *me,
+                                                   const Elf_Shdr *s)
+{
+       char *start, *end;
+       int numpages;
+       size_t size;
+
+       size = FTRACE_HOTPATCH_TRAMPOLINES_SIZE(s->sh_size);
+       numpages = DIV_ROUND_UP(size, PAGE_SIZE);
+       start = module_alloc(numpages * PAGE_SIZE);
+       if (!start)
+               return -ENOMEM;
+       set_memory_ro((unsigned long)start, numpages);
+       end = start + size;
+
+       me->arch.trampolines_start = (struct ftrace_hotpatch_trampoline *)start;
+       me->arch.trampolines_end = (struct ftrace_hotpatch_trampoline *)end;
+       me->arch.next_trampoline = me->arch.trampolines_start;
+
+       return 0;
+}
+#endif /* CONFIG_FUNCTION_TRACER */
+
 int module_finalize(const Elf_Ehdr *hdr,
                    const Elf_Shdr *sechdrs,
                    struct module *me)
@@ -473,6 +507,9 @@ int module_finalize(const Elf_Ehdr *hdr,
        const Elf_Shdr *s;
        char *secstrings, *secname;
        void *aseg;
+#ifdef CONFIG_FUNCTION_TRACER
+       int ret;
+#endif
 
        if (IS_ENABLED(CONFIG_EXPOLINE) &&
            !nospec_disable && me->arch.plt_size) {
@@ -507,6 +544,14 @@ int module_finalize(const Elf_Ehdr *hdr,
                if (IS_ENABLED(CONFIG_EXPOLINE) &&
                    (str_has_prefix(secname, ".s390_return")))
                        nospec_revert(aseg, aseg + s->sh_size);
+
+#ifdef CONFIG_FUNCTION_TRACER
+               if (!strcmp(FTRACE_CALLSITE_SECTION, secname)) {
+                       ret = module_alloc_ftrace_hotpatch_trampolines(me, s);
+                       if (ret < 0)
+                               return ret;
+               }
+#endif /* CONFIG_FUNCTION_TRACER */
        }
 
        jump_label_apply_nops(me);