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-rw-r--r--arch/s390/kernel/module.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
index 4055f1c49814..b01ba460b7ca 100644
--- 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);