4 files changed, 26 insertions, 22 deletions

diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 524d23b8610c..4f289ff0b7fe 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -599,10 +599,10 @@ static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste)
         skey = page_get_storage_key(address);
         bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
         /* Clear page changed & referenced bit in the storage key */
-        if (bits) {
-                skey ^= bits;
-                page_set_storage_key(address, skey, 1);
-        }
+        if (bits & _PAGE_CHANGED)
+                page_set_storage_key(address, skey ^ bits, 1);
+        else if (bits)
+                page_reset_referenced(address);
         /* Transfer page changed & referenced bit to guest bits in pgste */
         pgste_val(pgste) |= bits << 48;         /* RCP_GR_BIT & RCP_GC_BIT */
         /* Get host changed & referenced bits from pgste */
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 450931a45b68..573bc29551ef 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -296,13 +296,6 @@ static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
                      ((data & PSW_MASK_EA) && !(data & PSW_MASK_BA))))
                         /* Invalid psw mask. */
                         return -EINVAL;
-                if (addr == (addr_t) &dummy->regs.psw.addr)
-                        /*
-                         * The debugger changed the instruction address,
-                         * reset system call restart, see signal.c:do_signal
-                         */
-                        task_thread_info(child)->system_call = 0;
-
                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 
         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
@@ -614,11 +607,6 @@ static int __poke_user_compat(struct task_struct *child,
                         /* Transfer 31 bit amode bit to psw mask. */
                         regs->psw.mask = (regs->psw.mask & ~PSW_MASK_BA) |
                                 (__u64)(tmp & PSW32_ADDR_AMODE);
-                        /*
-                         * The debugger changed the instruction address,
-                         * reset system call restart, see signal.c:do_signal
-                         */
-                        task_thread_info(child)->system_call = 0;
                 } else {
                         /* gpr 0-15 */
                         *(__u32*)((addr_t) &regs->psw + addr*2 + 4) = tmp;
@@ -905,6 +893,14 @@ static int s390_last_break_get(struct task_struct *target,
         return 0;
 }
 
+static int s390_last_break_set(struct task_struct *target,
+                               const struct user_regset *regset,
+                               unsigned int pos, unsigned int count,
+                               const void *kbuf, const void __user *ubuf)
+{
+        return 0;
+}
+
 #endif
 
 static int s390_system_call_get(struct task_struct *target,
@@ -951,6 +947,7 @@ static const struct user_regset s390_regsets[] = {
                 .size = sizeof(long),
                 .align = sizeof(long),
                 .get = s390_last_break_get,
+                .set = s390_last_break_set,
         },
 #endif
         [REGSET_SYSTEM_CALL] = {
@@ -1116,6 +1113,14 @@ static int s390_compat_last_break_get(struct task_struct *target,
         return 0;
 }
 
+static int s390_compat_last_break_set(struct task_struct *target,
+                                      const struct user_regset *regset,
+                                      unsigned int pos, unsigned int count,
+                                      const void *kbuf, const void __user *ubuf)
+{
+        return 0;
+}
+
 static const struct user_regset s390_compat_regsets[] = {
         [REGSET_GENERAL] = {
                 .core_note_type = NT_PRSTATUS,
@@ -1139,6 +1144,7 @@ static const struct user_regset s390_compat_regsets[] = {
                 .size = sizeof(long),
                 .align = sizeof(long),
                 .get = s390_compat_last_break_get,
+                .set = s390_compat_last_break_set,
         },
         [REGSET_SYSTEM_CALL] = {
                 .core_note_type = NT_S390_SYSTEM_CALL,
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index e58a462949b1..e54c4ff8abaa 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -579,7 +579,7 @@ static unsigned long __init find_crash_base(unsigned long crash_size,
                 *msg = "first memory chunk must be at least crashkernel size";
                 return 0;
         }
-        if (is_kdump_kernel() && (crash_size == OLDMEM_SIZE))
+        if (OLDMEM_BASE && crash_size == OLDMEM_SIZE)
                 return OLDMEM_BASE;
 
         for (i = MEMORY_CHUNKS - 1; i >= 0; i--) {
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 05a85bc14c98..7f6f9f354545 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -460,9 +460,9 @@ void do_signal(struct pt_regs *regs)
                                                      regs->svc_code >> 16);
                                 break;
                         }
-                        /* No longer in a system call */
-                        clear_thread_flag(TIF_SYSCALL);
                 }
+                /* No longer in a system call */
+                clear_thread_flag(TIF_SYSCALL);
 
                 if ((is_compat_task() ?
                      handle_signal32(signr, &ka, &info, oldset, regs) :
@@ -486,6 +486,7 @@ void do_signal(struct pt_regs *regs)
         }
 
         /* No handlers present - check for system call restart */
+        clear_thread_flag(TIF_SYSCALL);
         if (current_thread_info()->system_call) {
                 regs->svc_code = current_thread_info()->system_call;
                 switch (regs->gprs[2]) {
@@ -500,9 +501,6 @@ void do_signal(struct pt_regs *regs)
                         regs->gprs[2] = regs->orig_gpr2;
                         set_thread_flag(TIF_SYSCALL);
                         break;
-                default:
-                        clear_thread_flag(TIF_SYSCALL);
-                        break;
                 }
         }