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Diffstat (limited to 'arch/s390/kernel')
-rw-r--r--arch/s390/kernel/ftrace.c37
-rw-r--r--arch/s390/kernel/mcount.S9
-rw-r--r--arch/s390/kernel/setup.c2
3 files changed, 47 insertions, 1 deletions
diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 1db9cc795034..d8b96c5923c0 100644
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -158,9 +158,38 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec)
return 0;
}
+static struct ftrace_hotpatch_trampoline *ftrace_get_trampoline(struct dyn_ftrace *rec)
+{
+ struct ftrace_hotpatch_trampoline *trampoline;
+ struct ftrace_insn insn;
+ s64 disp;
+ u16 opc;
+
+ if (copy_from_kernel_nofault(&insn, (void *)rec->ip, sizeof(insn)))
+ return ERR_PTR(-EFAULT);
+ disp = (s64)insn.disp * 2;
+ trampoline = (void *)(rec->ip + disp);
+ if (get_kernel_nofault(opc, &trampoline->brasl_opc))
+ return ERR_PTR(-EFAULT);
+ if (opc != 0xc015)
+ return ERR_PTR(-EINVAL);
+ return trampoline;
+}
+
int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
unsigned long addr)
{
+ struct ftrace_hotpatch_trampoline *trampoline;
+ u64 old;
+
+ trampoline = ftrace_get_trampoline(rec);
+ if (IS_ERR(trampoline))
+ return PTR_ERR(trampoline);
+ if (get_kernel_nofault(old, &trampoline->interceptor))
+ return -EFAULT;
+ if (old != old_addr)
+ return -EINVAL;
+ s390_kernel_write(&trampoline->interceptor, &addr, sizeof(addr));
return 0;
}
@@ -188,6 +217,12 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
{
+ struct ftrace_hotpatch_trampoline *trampoline;
+
+ trampoline = ftrace_get_trampoline(rec);
+ if (IS_ERR(trampoline))
+ return PTR_ERR(trampoline);
+ s390_kernel_write(&trampoline->interceptor, &addr, sizeof(addr));
/* Expect brcl 0x0,... */
return ftrace_patch_branch_mask((void *)rec->ip, 0xc004, true);
}
@@ -301,7 +336,7 @@ void kprobe_ftrace_handler(unsigned long ip, unsigned long parent_ip,
regs = ftrace_get_regs(fregs);
p = get_kprobe((kprobe_opcode_t *)ip);
- if (unlikely(!p) || kprobe_disabled(p))
+ if (!regs || unlikely(!p) || kprobe_disabled(p))
goto out;
if (kprobe_running()) {
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
index a06eb86c178f..9d90b8bc6692 100644
--- a/arch/s390/kernel/mcount.S
+++ b/arch/s390/kernel/mcount.S
@@ -25,6 +25,7 @@ ENDPROC(ftrace_stub)
#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
#define STACK_PTREGS_ORIG_GPR2 (STACK_PTREGS + __PT_ORIG_GPR2)
+#define STACK_PTREGS_FLAGS (STACK_PTREGS + __PT_FLAGS)
#ifdef __PACK_STACK
/* allocate just enough for r14, r15 and backchain */
#define TRACED_FUNC_FRAME_SIZE 24
@@ -55,6 +56,14 @@ ENDPROC(ftrace_stub)
.if \allregs == 1
stg %r14,(STACK_PTREGS_PSW)(%r15)
stosm (STACK_PTREGS_PSW)(%r15),0
+#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES
+ mvghi STACK_PTREGS_FLAGS(%r15),_PIF_FTRACE_FULL_REGS
+#else
+ lghi %r14,_PIF_FTRACE_FULL_REGS
+ stg %r14,STACK_PTREGS_FLAGS(%r15)
+#endif
+ .else
+ xc STACK_PTREGS_FLAGS(8,%r15),STACK_PTREGS_FLAGS(%r15)
.endif
lg %r14,(__SF_GPRS+8*8)(%r1) # restore original return address
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index f2c25d113e7b..05327be3a982 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -800,6 +800,8 @@ static void __init check_initrd(void)
static void __init reserve_kernel(void)
{
memblock_reserve(0, STARTUP_NORMAL_OFFSET);
+ memblock_reserve(OLDMEM_BASE, sizeof(unsigned long));
+ memblock_reserve(OLDMEM_SIZE, sizeof(unsigned long));
memblock_reserve(__amode31_base, __eamode31 - __samode31);
memblock_reserve(__pa(sclp_early_sccb), EXT_SCCB_READ_SCP);
memblock_reserve(__pa(_stext), _end - _stext);