[Qemu-devel] [PATCH v5] s390: Implement dump-guest-memory support for target s390x

[Qemu-devel] [PATCH v5] s390: Implement dump-guest-memory support for target s390x

[Jens Freimann]

With this patch dump-guest-memory on s390 produces an ELF formatted,
crash-readable dump.
In order to implement this, the arch-specific part of dump-guest-memory
was added:
target-s390x/arch_dump.c contains the whole set of function for writing
Elf note sections of all types for s390x.

Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
[fixed indentation, use CamelCase, rename note_t to Note, use S390CPU]
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

---
v4->v5:
 - remove include of cpu-qom.h in arch_dump.c

---
 include/elf.h              |   6 ++
 target-s390x/Makefile.objs |   2 +-
 target-s390x/arch_dump.c   | 212 +++++++++++++++++++++++++++++++++++++++++++++
 target-s390x/cpu-qom.h     |   5 ++
 target-s390x/cpu.c         |   4 +
 5 files changed, 228 insertions(+), 1 deletion(-)
 create mode 100644 target-s390x/arch_dump.c

diff --git a/include/elf.h b/include/elf.h
index cf0d3e2..58bfbf8 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 4e63417..c34f654 100644
--- a/target-s390x/Makefile.objs
+++ b/target-s390x/Makefile.objs
@@ -1,4 +1,4 @@
 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-$(CONFIG_SOFTMMU) += ioinst.o
+obj-$(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 0000000..f3e5144
--- /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 ec32d21..4f38686 100644
--- a/target-s390x/cpu-qom.h
+++ b/target-s390x/cpu-qom.h
@@ -74,5 +74,10 @@ 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);
 
 #endif
diff --git a/target-s390x/cpu.c b/target-s390x/cpu.c
index c3697cd..71d9fc7 100644
--- a/target-s390x/cpu.c
+++ b/target-s390x/cpu.c
@@ -171,6 +171,10 @@ static void s390_cpu_class_init(ObjectClass *oc, void *data)
     cc->do_interrupt = s390_cpu_do_interrupt;
     cc->dump_state = s390_cpu_dump_state;
     dc->vmsd = &vmstate_s390_cpu;
+#ifndef CONFIG_USER_ONLY
+    cc->write_elf64_note = s390_cpu_write_elf64_note;
+    cc->write_elf64_qemunote = s390_cpu_write_elf64_qemunote;
+#endif
 }
 
 static const TypeInfo s390_cpu_type_info = {
-- 
1.8.2.2

Re: [Qemu-devel] [PATCH v5] s390: Implement dump-guest-memory support for target s390x

[Andreas Färber]

Am 10.07.2013 15:26, schrieb Jens Freimann:
> With this patch dump-guest-memory on s390 produces an ELF formatted,
> crash-readable dump.
> In order to implement this, the arch-specific part of dump-guest-memory
> was added:
> target-s390x/arch_dump.c contains the whole set of function for writing
> Elf note sections of all types for s390x.
> 
> Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
> Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
> [fixed indentation, use CamelCase, rename note_t to Note, use S390CPU]
> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
> 
> ---
> v4->v5:
>  - remove include of cpu-qom.h in arch_dump.c

Thanks,

Reviewed-by: Andreas Färber <afaerber@suse.de>

Andreas

-- 
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg

Re: [Qemu-devel] [PATCH v5] s390: Implement dump-guest-memory support for target s390x

[Christian Borntraeger]

Ping?


On 10/07/13 15:26, Jens Freimann wrote:
> With this patch dump-guest-memory on s390 produces an ELF formatted,
> crash-readable dump.
> In order to implement this, the arch-specific part of dump-guest-memory
> was added:
> target-s390x/arch_dump.c contains the whole set of function for writing
> Elf note sections of all types for s390x.
> 
> Signed-off-by: Ekaterina Tumanova <tumanova@linux.vnet.ibm.com>
> Signed-off-by: Jens Freimann <jfrei@linux.vnet.ibm.com>
> [fixed indentation, use CamelCase, rename note_t to Note, use S390CPU]
> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
> 
> ---
> v4->v5:
>  - remove include of cpu-qom.h in arch_dump.c
> 
> ---
>  include/elf.h              |   6 ++
>  target-s390x/Makefile.objs |   2 +-
>  target-s390x/arch_dump.c   | 212 +++++++++++++++++++++++++++++++++++++++++++++
>  target-s390x/cpu-qom.h     |   5 ++
>  target-s390x/cpu.c         |   4 +
>  5 files changed, 228 insertions(+), 1 deletion(-)
>  create mode 100644 target-s390x/arch_dump.c
> 
> diff --git a/include/elf.h b/include/elf.h
> index cf0d3e2..58bfbf8 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 4e63417..c34f654 100644
> --- a/target-s390x/Makefile.objs
> +++ b/target-s390x/Makefile.objs
> @@ -1,4 +1,4 @@
>  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-$(CONFIG_SOFTMMU) += ioinst.o
> +obj-$(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 0000000..f3e5144
> --- /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 ec32d21..4f38686 100644
> --- a/target-s390x/cpu-qom.h
> +++ b/target-s390x/cpu-qom.h
> @@ -74,5 +74,10 @@ 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);
> 
>  #endif
> diff --git a/target-s390x/cpu.c b/target-s390x/cpu.c
> index c3697cd..71d9fc7 100644
> --- a/target-s390x/cpu.c
> +++ b/target-s390x/cpu.c
> @@ -171,6 +171,10 @@ static void s390_cpu_class_init(ObjectClass *oc, void *data)
>      cc->do_interrupt = s390_cpu_do_interrupt;
>      cc->dump_state = s390_cpu_dump_state;
>      dc->vmsd = &vmstate_s390_cpu;
> +#ifndef CONFIG_USER_ONLY
> +    cc->write_elf64_note = s390_cpu_write_elf64_note;
> +    cc->write_elf64_qemunote = s390_cpu_write_elf64_qemunote;
> +#endif
>  }
> 
>  static const TypeInfo s390_cpu_type_info = {
>