Merge remote-tracking branch 'borntraeger/s390-for-1.6' into staging

* borntraeger/s390-for-1.6:
  s390: Implement dump-guest-memory support for target s390x
  s390x/kvm: Remove redundant return code
  s390x/kvm: Reworked/fixed handling of cc3 in kvm_handle_css_inst()
  s390x/ioinst: Fixed priority of operand exceptions
  s390x/ioinst: Fixed alignment check in SCHM instruction
  s390x/ioinst: Throw addressing exception when memory_map failed
  s390x/ioinst: Add missing alignment checks for IO instructions
  s390/sclpconsole: handle char layer busy conditions

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

8 files changed, 283 insertions, 91 deletions

diff --git a/hw/char/sclpconsole.c b/hw/char/sclpconsole.c
index bcc7893230..eb3988c2e4 100644
--- a/hw/char/sclpconsole.c
+++ b/hw/char/sclpconsole.c
@@ -184,8 +184,6 @@ static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
 static ssize_t write_console_data(SCLPEvent *event, const uint8_t *buf,
                                   size_t len)
 {
-    ssize_t ret = 0;
-    const uint8_t *iov_offset;
     SCLPConsole *scon = DO_UPCAST(SCLPConsole, event, event);
 
     if (!scon->chr) {
@@ -193,21 +191,7 @@ static ssize_t write_console_data(SCLPEvent *event, const uint8_t *buf,
         return len;
     }
 
-    iov_offset = buf;
-    while (len > 0) {
-        ret = qemu_chr_fe_write(scon->chr, buf, len);
-        if (ret == 0) {
-            /* a pty doesn't seem to be connected - no error */
-            len = 0;
-        } else if (ret == -EAGAIN || (ret > 0 && ret < len)) {
-            len -= ret;
-            iov_offset += ret;
-        } else {
-            len = 0;
-        }
-    }
-
-    return ret;
+    return qemu_chr_fe_write_all(scon->chr, buf, len);
 }
 
 static int write_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr)
diff --git a/include/elf.h b/include/elf.h
index cf0d3e2bd6..58bfbf8817 100644
--- a/include/elf.h
+++ b/include/elf.h
@@ -1348,11 +1348,17 @@ typedef struct elf64_shdr {
 
 /* Notes used in ET_CORE */
 #define NT_PRSTATUS	1
+#define NT_FPREGSET     2
 #define NT_PRFPREG	2
 #define NT_PRPSINFO	3
 #define NT_TASKSTRUCT	4
 #define NT_AUXV		6
 #define NT_PRXFPREG     0x46e62b7f      /* copied from gdb5.1/include/elf/common.h */
+#define NT_S390_PREFIX  0x305           /* s390 prefix register */
+#define NT_S390_CTRS    0x304           /* s390 control registers */
+#define NT_S390_TODPREG 0x303           /* s390 TOD programmable register */
+#define NT_S390_TODCMP  0x302           /* s390 TOD clock comparator register */
+#define NT_S390_TIMER   0x301           /* s390 timer register */
 
 
 /* Note header in a PT_NOTE section */
diff --git a/target-s390x/Makefile.objs b/target-s390x/Makefile.objs
index ab938e7ad8..f8731463ff 100644
--- a/target-s390x/Makefile.objs
+++ b/target-s390x/Makefile.objs
@@ -1,5 +1,5 @@
 obj-y += translate.o helper.o cpu.o interrupt.o
 obj-y += int_helper.o fpu_helper.o cc_helper.o mem_helper.o misc_helper.o
 obj-y += gdbstub.o
-obj-$(CONFIG_SOFTMMU) += ioinst.o
+obj-$(CONFIG_SOFTMMU) += ioinst.o arch_dump.o
 obj-$(CONFIG_KVM) += kvm.o
diff --git a/target-s390x/arch_dump.c b/target-s390x/arch_dump.c
new file mode 100644
index 0000000000..f3e5144cc1
--- /dev/null
+++ b/target-s390x/arch_dump.c
@@ -0,0 +1,212 @@
+/*
+ * writing ELF notes for s390x arch
+ *
+ *
+ * Copyright IBM Corp. 2012, 2013
+ *
+ *     Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "cpu.h"
+#include "elf.h"
+#include "exec/cpu-all.h"
+#include "sysemu/dump.h"
+#include "sysemu/kvm.h"
+
+
+struct S390xUserRegsStruct {
+    uint64_t psw[2];
+    uint64_t gprs[16];
+    uint32_t acrs[16];
+} QEMU_PACKED;
+
+typedef struct S390xUserRegsStruct S390xUserRegs;
+
+struct S390xElfPrstatusStruct {
+    uint8_t pad1[32];
+    uint32_t pid;
+    uint8_t pad2[76];
+    S390xUserRegs regs;
+    uint8_t pad3[16];
+} QEMU_PACKED;
+
+typedef struct S390xElfPrstatusStruct S390xElfPrstatus;
+
+struct S390xElfFpregsetStruct {
+    uint32_t fpc;
+    uint32_t pad;
+    uint64_t fprs[16];
+} QEMU_PACKED;
+
+typedef struct S390xElfFpregsetStruct S390xElfFpregset;
+
+typedef struct noteStruct {
+    Elf64_Nhdr hdr;
+    char name[5];
+    char pad3[3];
+    union {
+        S390xElfPrstatus prstatus;
+        S390xElfFpregset fpregset;
+        uint32_t prefix;
+        uint64_t timer;
+        uint64_t todcmp;
+        uint32_t todpreg;
+        uint64_t ctrs[16];
+    } contents;
+} QEMU_PACKED Note;
+
+static void s390x_write_elf64_prstatus(Note *note, S390CPU *cpu)
+{
+    int i;
+    S390xUserRegs *regs;
+
+    note->hdr.n_type = cpu_to_be32(NT_PRSTATUS);
+
+    regs = &(note->contents.prstatus.regs);
+    regs->psw[0] = cpu_to_be64(cpu->env.psw.mask);
+    regs->psw[1] = cpu_to_be64(cpu->env.psw.addr);
+    for (i = 0; i <= 15; i++) {
+        regs->acrs[i] = cpu_to_be32(cpu->env.aregs[i]);
+        regs->gprs[i] = cpu_to_be64(cpu->env.regs[i]);
+    }
+}
+
+static void s390x_write_elf64_fpregset(Note *note, S390CPU *cpu)
+{
+    int i;
+
+    note->hdr.n_type = cpu_to_be32(NT_FPREGSET);
+    note->contents.fpregset.fpc = cpu_to_be32(cpu->env.fpc);
+    for (i = 0; i <= 15; i++) {
+        note->contents.fpregset.fprs[i] = cpu_to_be64(cpu->env.fregs[i].ll);
+    }
+}
+
+
+static void s390x_write_elf64_timer(Note *note, S390CPU *cpu)
+{
+    note->hdr.n_type = cpu_to_be32(NT_S390_TIMER);
+    note->contents.timer = cpu_to_be64((uint64_t)(cpu->env.cputm));
+}
+
+static void s390x_write_elf64_todcmp(Note *note, S390CPU *cpu)
+{
+    note->hdr.n_type = cpu_to_be32(NT_S390_TODCMP);
+    note->contents.todcmp = cpu_to_be64((uint64_t)(cpu->env.ckc));
+}
+
+static void s390x_write_elf64_todpreg(Note *note, S390CPU *cpu)
+{
+    note->hdr.n_type = cpu_to_be32(NT_S390_TODPREG);
+    note->contents.todpreg = cpu_to_be32((uint32_t)(cpu->env.todpr));
+}
+
+static void s390x_write_elf64_ctrs(Note *note, S390CPU *cpu)
+{
+    int i;
+
+    note->hdr.n_type = cpu_to_be32(NT_S390_CTRS);
+
+    for (i = 0; i <= 15; i++) {
+        note->contents.ctrs[i] = cpu_to_be64(cpu->env.cregs[i]);
+    }
+}
+
+static void s390x_write_elf64_prefix(Note *note, S390CPU *cpu)
+{
+    note->hdr.n_type = cpu_to_be32(NT_S390_PREFIX);
+    note->contents.prefix = cpu_to_be32((uint32_t)(cpu->env.psa));
+}
+
+
+struct NoteFuncDescStruct {
+    int contents_size;
+    void (*note_contents_func)(Note *note, S390CPU *cpu);
+} note_func[] = {
+    {sizeof(((Note *)0)->contents.prstatus), s390x_write_elf64_prstatus},
+    {sizeof(((Note *)0)->contents.prefix),   s390x_write_elf64_prefix},
+    {sizeof(((Note *)0)->contents.fpregset), s390x_write_elf64_fpregset},
+    {sizeof(((Note *)0)->contents.ctrs),     s390x_write_elf64_ctrs},
+    {sizeof(((Note *)0)->contents.timer),    s390x_write_elf64_timer},
+    {sizeof(((Note *)0)->contents.todcmp),   s390x_write_elf64_todcmp},
+    {sizeof(((Note *)0)->contents.todpreg),  s390x_write_elf64_todpreg},
+    { 0, NULL}
+};
+
+typedef struct NoteFuncDescStruct NoteFuncDesc;
+
+
+static int s390x_write_all_elf64_notes(const char *note_name,
+                                       WriteCoreDumpFunction f,
+                                       S390CPU *cpu, int id,
+                                       void *opaque)
+{
+    Note note;
+    NoteFuncDesc *nf;
+    int note_size;
+    int ret = -1;
+
+    for (nf = note_func; nf->note_contents_func; nf++) {
+        note.hdr.n_namesz = cpu_to_be32(sizeof(note.name));
+        note.hdr.n_descsz = cpu_to_be32(nf->contents_size);
+        strncpy(note.name, note_name, sizeof(note.name));
+        (*nf->note_contents_func)(&note, cpu);
+
+        note_size = sizeof(note) - sizeof(note.contents) + nf->contents_size;
+        ret = f(&note, note_size, opaque);
+
+        if (ret < 0) {
+            return -1;
+        }
+
+    }
+
+    return 0;
+}
+
+
+int s390_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
+                              int cpuid, void *opaque)
+{
+    S390CPU *cpu = S390_CPU(cs);
+    return s390x_write_all_elf64_notes("CORE", f, cpu, cpuid, opaque);
+}
+
+int cpu_get_dump_info(ArchDumpInfo *info)
+{
+    info->d_machine = EM_S390;
+    info->d_endian = ELFDATA2MSB;
+    info->d_class = ELFCLASS64;
+
+    return 0;
+}
+
+ssize_t cpu_get_note_size(int class, int machine, int nr_cpus)
+{
+    int name_size = 8; /* "CORE" or "QEMU" rounded */
+    size_t elf_note_size = 0;
+    int note_head_size;
+    NoteFuncDesc *nf;
+
+    assert(class == ELFCLASS64);
+    assert(machine == EM_S390);
+
+    note_head_size = sizeof(Elf64_Nhdr);
+
+    for (nf = note_func; nf->note_contents_func; nf++) {
+        elf_note_size = elf_note_size + note_head_size + name_size +
+                        nf->contents_size;
+    }
+
+    return (elf_note_size) * nr_cpus;
+}
+
+int s390_cpu_write_elf64_qemunote(WriteCoreDumpFunction f,
+                                  CPUState *cpu, void *opaque)
+{
+    return 0;
+}
diff --git a/target-s390x/cpu-qom.h b/target-s390x/cpu-qom.h
index 0d63b1cf20..cbe2341b3b 100644
--- a/target-s390x/cpu-qom.h
+++ b/target-s390x/cpu-qom.h
@@ -74,6 +74,11 @@ static inline S390CPU *s390_env_get_cpu(CPUS390XState *env)
 void s390_cpu_do_interrupt(CPUState *cpu);
 void s390_cpu_dump_state(CPUState *cpu, FILE *f, fprintf_function cpu_fprintf,
                          int flags);
+int s390_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
+                              int cpuid, void *opaque);
+
+int s390_cpu_write_elf64_qemunote(WriteCoreDumpFunction f,
+                                  CPUState *cpu, void *opaque);
 hwaddr s390_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
 int s390_cpu_gdb_read_register(CPUState *cpu, uint8_t *buf, int reg);
 int s390_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
diff --git a/target-s390x/cpu.c b/target-s390x/cpu.c
index 9b824957f6..6be6c084a7 100644
--- a/target-s390x/cpu.c
+++ b/target-s390x/cpu.c
@@ -178,6 +178,8 @@ static void s390_cpu_class_init(ObjectClass *oc, void *data)
     cc->gdb_write_register = s390_cpu_gdb_write_register;
 #ifndef CONFIG_USER_ONLY
     cc->get_phys_page_debug = s390_cpu_get_phys_page_debug;
+    cc->write_elf64_note = s390_cpu_write_elf64_note;
+    cc->write_elf64_qemunote = s390_cpu_write_elf64_qemunote;
 #endif
     dc->vmsd = &vmstate_s390_cpu;
     cc->gdb_num_core_regs = S390_NUM_REGS;
diff --git a/target-s390x/ioinst.c b/target-s390x/ioinst.c
index 28c508d541..85fd285736 100644
--- a/target-s390x/ioinst.c
+++ b/target-s390x/ioinst.c
@@ -151,23 +151,24 @@ int ioinst_handle_msch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
     int cc;
     hwaddr len = sizeof(*schib);
 
-    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
-        program_interrupt(env, PGM_OPERAND, 2);
+    addr = decode_basedisp_s(env, ipb);
+    if (addr & 3) {
+        program_interrupt(env, PGM_SPECIFICATION, 2);
         return -EIO;
     }
-    trace_ioinst_sch_id("msch", cssid, ssid, schid);
-    addr = decode_basedisp_s(env, ipb);
     schib = s390_cpu_physical_memory_map(env, addr, &len, 0);
     if (!schib || len != sizeof(*schib)) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
         cc = -EIO;
         goto out;
     }
-    if (!ioinst_schib_valid(schib)) {
+    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid) ||
+        !ioinst_schib_valid(schib)) {
         program_interrupt(env, PGM_OPERAND, 2);
         cc = -EIO;
         goto out;
     }
+    trace_ioinst_sch_id("msch", cssid, ssid, schid);
     sch = css_find_subch(m, cssid, ssid, schid);
     if (sch && css_subch_visible(sch)) {
         ret = css_do_msch(sch, schib);
@@ -222,24 +223,25 @@ int ioinst_handle_ssch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
     int cc;
     hwaddr len = sizeof(*orig_orb);
 
-    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
-        program_interrupt(env, PGM_OPERAND, 2);
+    addr = decode_basedisp_s(env, ipb);
+    if (addr & 3) {
+        program_interrupt(env, PGM_SPECIFICATION, 2);
         return -EIO;
     }
-    trace_ioinst_sch_id("ssch", cssid, ssid, schid);
-    addr = decode_basedisp_s(env, ipb);
     orig_orb = s390_cpu_physical_memory_map(env, addr, &len, 0);
     if (!orig_orb || len != sizeof(*orig_orb)) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
         cc = -EIO;
         goto out;
     }
     copy_orb_from_guest(&orb, orig_orb);
-    if (!ioinst_orb_valid(&orb)) {
+    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid) ||
+        !ioinst_orb_valid(&orb)) {
         program_interrupt(env, PGM_OPERAND, 2);
         cc = -EIO;
         goto out;
     }
+    trace_ioinst_sch_id("ssch", cssid, ssid, schid);
     sch = css_find_subch(m, cssid, ssid, schid);
     if (sch && css_subch_visible(sch)) {
         ret = css_do_ssch(sch, &orb);
@@ -272,9 +274,13 @@ int ioinst_handle_stcrw(CPUS390XState *env, uint32_t ipb)
     hwaddr len = sizeof(*crw);
 
     addr = decode_basedisp_s(env, ipb);
+    if (addr & 3) {
+        program_interrupt(env, PGM_SPECIFICATION, 2);
+        return -EIO;
+    }
     crw = s390_cpu_physical_memory_map(env, addr, &len, 1);
     if (!crw || len != sizeof(*crw)) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
         cc = -EIO;
         goto out;
     }
@@ -294,18 +300,24 @@ int ioinst_handle_stsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
     SCHIB *schib;
     hwaddr len = sizeof(*schib);
 
-    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
-        program_interrupt(env, PGM_OPERAND, 2);
+    addr = decode_basedisp_s(env, ipb);
+    if (addr & 3) {
+        program_interrupt(env, PGM_SPECIFICATION, 2);
         return -EIO;
     }
-    trace_ioinst_sch_id("stsch", cssid, ssid, schid);
-    addr = decode_basedisp_s(env, ipb);
     schib = s390_cpu_physical_memory_map(env, addr, &len, 1);
     if (!schib || len != sizeof(*schib)) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
+        cc = -EIO;
+        goto out;
+    }
+
+    if (ioinst_disassemble_sch_ident(reg1, &m, &cssid, &ssid, &schid)) {
+        program_interrupt(env, PGM_OPERAND, 2);
         cc = -EIO;
         goto out;
     }
+    trace_ioinst_sch_id("stsch", cssid, ssid, schid);
     sch = css_find_subch(m, cssid, ssid, schid);
     if (sch) {
         if (css_subch_visible(sch)) {
@@ -345,9 +357,13 @@ int ioinst_handle_tsch(CPUS390XState *env, uint64_t reg1, uint32_t ipb)
     }
     trace_ioinst_sch_id("tsch", cssid, ssid, schid);
     addr = decode_basedisp_s(env, ipb);
+    if (addr & 3) {
+        program_interrupt(env, PGM_SPECIFICATION, 2);
+        return -EIO;
+    }
     irb = s390_cpu_physical_memory_map(env, addr, &len, 1);
     if (!irb || len != sizeof(*irb)) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
         cc = -EIO;
         goto out;
     }
@@ -580,7 +596,7 @@ int ioinst_handle_chsc(CPUS390XState *env, uint32_t ipb)
     }
     req = s390_cpu_physical_memory_map(env, addr, &map_size, 1);
     if (!req || map_size != TARGET_PAGE_SIZE) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
         ret = -EIO;
         goto out;
     }
@@ -625,12 +641,17 @@ int ioinst_handle_tpi(CPUS390XState *env, uint32_t ipb)
 
     trace_ioinst("tpi");
     addr = decode_basedisp_s(env, ipb);
+    if (addr & 3) {
+        program_interrupt(env, PGM_SPECIFICATION, 2);
+        return -EIO;
+    }
+
     lowcore = addr ? 0 : 1;
     len = lowcore ? 8 /* two words */ : 12 /* three words */;
     orig_len = len;
     int_code = s390_cpu_physical_memory_map(env, addr, &len, 1);
     if (!int_code || (len != orig_len)) {
-        program_interrupt(env, PGM_SPECIFICATION, 2);
+        program_interrupt(env, PGM_ADDRESSING, 2);
         ret = -EIO;
         goto out;
     }
@@ -663,7 +684,7 @@ int ioinst_handle_schm(CPUS390XState *env, uint64_t reg1, uint64_t reg2,
     update = SCHM_REG1_UPD(reg1);
     dct = SCHM_REG1_DCT(reg1);
 
-    if (update && (reg2 & 0x0000000000000fff)) {
+    if (update && (reg2 & 0x000000000000001f)) {
         program_interrupt(env, PGM_OPERAND, 2);
         return -EIO;
     }
diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index ab0e2b505f..26d18e3bcf 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -528,50 +528,19 @@ static int kvm_handle_css_inst(S390CPU *cpu, struct kvm_run *run,
         no_cc = 1;
         r = ioinst_handle_sal(env, env->regs[1]);
         break;
-    default:
-        r = -1;
+    case PRIV_SIGA:
+        /* Not provided, set CC = 3 for subchannel not operational */
+        r = 3;
         break;
+    default:
+        return -1;
     }
 
-    if (r >= 0) {
-        if (!no_cc) {
-            setcc(cpu, r);
-        }
-        r = 0;
-    } else if (r < -1) {
-        r = 0;
+    if (r >= 0 && !no_cc) {
+        setcc(cpu, r);
     }
-    return r;
-}
 
-static int is_ioinst(uint8_t ipa0, uint8_t ipa1, uint8_t ipb)
-{
-    int ret = 0;
-    uint16_t ipa = (ipa0 << 8) | ipa1;
-
-    switch (ipa) {
-    case IPA0_B2 | PRIV_CSCH:
-    case IPA0_B2 | PRIV_HSCH:
-    case IPA0_B2 | PRIV_MSCH:
-    case IPA0_B2 | PRIV_SSCH:
-    case IPA0_B2 | PRIV_STSCH:
-    case IPA0_B2 | PRIV_TPI:
-    case IPA0_B2 | PRIV_SAL:
-    case IPA0_B2 | PRIV_RSCH:
-    case IPA0_B2 | PRIV_STCRW:
-    case IPA0_B2 | PRIV_STCPS:
-    case IPA0_B2 | PRIV_RCHP:
-    case IPA0_B2 | PRIV_SCHM:
-    case IPA0_B2 | PRIV_CHSC:
-    case IPA0_B2 | PRIV_SIGA:
-    case IPA0_B2 | PRIV_XSCH:
-    case IPA0_B9 | PRIV_EQBS:
-    case IPA0_EB | PRIV_SQBS:
-        ret = 1;
-        break;
-    }
-
-    return ret;
+    return 0;
 }
 
 static int handle_priv(S390CPU *cpu, struct kvm_run *run,
@@ -587,15 +556,9 @@ static int handle_priv(S390CPU *cpu, struct kvm_run *run,
             r = kvm_sclp_service_call(cpu, run, ipbh0);
             break;
         default:
-            if (is_ioinst(ipa0, ipa1, ipb)) {
-                r = kvm_handle_css_inst(cpu, run, ipa0, ipa1, ipb);
-                if (r == -1) {
-                    setcc(cpu, 3);
-                    r = 0;
-                }
-            } else {
-                DPRINTF("KVM: unknown PRIV: 0x%x\n", ipa1);
-                r = -1;
+            r = kvm_handle_css_inst(cpu, run, ipa0, ipa1, ipb);
+            if (r == -1) {
+                DPRINTF("KVM: unhandled PRIV: 0x%x\n", ipa1);
             }
             break;
     }
@@ -730,7 +693,7 @@ out:
     return 0;
 }
 
-static int handle_instruction(S390CPU *cpu, struct kvm_run *run)
+static void handle_instruction(S390CPU *cpu, struct kvm_run *run)
 {
     unsigned int ipa0 = (run->s390_sieic.ipa & 0xff00);
     uint8_t ipa1 = run->s390_sieic.ipa & 0x00ff;
@@ -756,7 +719,6 @@ static int handle_instruction(S390CPU *cpu, struct kvm_run *run)
     if (r < 0) {
         enter_pgmcheck(cpu, 0x0001);
     }
-    return 0;
 }
 
 static bool is_special_wait_psw(CPUState *cs)
@@ -776,7 +738,7 @@ static int handle_intercept(S390CPU *cpu)
             (long)cs->kvm_run->psw_addr);
     switch (icpt_code) {
         case ICPT_INSTRUCTION:
-            r = handle_instruction(cpu, run);
+            handle_instruction(cpu, run);
             break;
         case ICPT_WAITPSW:
             /* disabled wait, since enabled wait is handled in kernel */