Re: [PATCH v6 09/10] s390x: Add KVM PV dump interface

[Marc-André Lureau]

Hi Janosch

On Mon, Oct 17, 2022 at 12:53 PM Janosch Frank <frankja@linux.ibm.com> wrote:

Let's add a few bits of code which hide the new KVM PV dump API from
us via new functions.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
---
 hw/s390x/pv.c         | 51 +++++++++++++++++++++++++++++++++++++++++++
 include/hw/s390x/pv.h |  9 ++++++++
 2 files changed, 60 insertions(+)

diff --git a/hw/s390x/pv.c b/hw/s390x/pv.c
index 4c012f2eeb..728ba24547 100644
--- a/hw/s390x/pv.c
+++ b/hw/s390x/pv.c
@@ -175,6 +175,57 @@ bool kvm_s390_pv_info_basic_valid(void)
     return info_valid;
 }

+static int s390_pv_dump_cmd(uint64_t subcmd, uint64_t uaddr, uint64_t gaddr,
+                            uint64_t len)
+{
+    struct kvm_s390_pv_dmp dmp = {
+        .subcmd = subcmd,
+        .buff_addr = uaddr,
+        .buff_len = len,
+        .gaddr = gaddr,
+    };
+    int ret;
+
+    ret = s390_pv_cmd(KVM_PV_DUMP, (void *)&dmp);
+    if (ret) {
+        error_report("KVM DUMP command %ld failed", subcmd);
+    }
+    return ret;
+}
+
+int kvm_s390_dump_cpu(S390CPU *cpu, void *buff)
+{
+    struct kvm_s390_pv_dmp dmp = {
+        .subcmd = KVM_PV_DUMP_CPU,
+        .buff_addr = (uint64_t)buff,
+        .gaddr = 0,
+        .buff_len = info_dump.dump_cpu_buffer_len,
+    };
+    struct kvm_pv_cmd pv = {
+        .cmd = KVM_PV_DUMP,
+        .data = ""> +    };
+
+    return kvm_vcpu_ioctl(CPU(cpu), KVM_S390_PV_CPU_COMMAND, &pv);
+}
+
+int kvm_s390_dump_init(void)
+{
+    return s390_pv_dump_cmd(KVM_PV_DUMP_INIT, 0, 0, 0);
+}
+
+int kvm_s390_dump_mem_state(uint64_t gaddr, size_t len, void *dest)
+{
+    return s390_pv_dump_cmd(KVM_PV_DUMP_CONFIG_STOR_STATE, (uint64_t)dest,
+                            gaddr, len);
+}
+
+int kvm_s390_dump_completion_data(void *buff)
+{
+    return s390_pv_dump_cmd(KVM_PV_DUMP_COMPLETE, (uint64_t)buff, 0,
+                            info_dump.dump_config_finalize_len);
+}
+
 #define TYPE_S390_PV_GUEST "s390-pv-guest"
 OBJECT_DECLARE_SIMPLE_TYPE(S390PVGuest, S390_PV_GUEST)

diff --git a/include/hw/s390x/pv.h b/include/hw/s390x/pv.h
index e5ea0eca16..3164006674 100644
--- a/include/hw/s390x/pv.h
+++ b/include/hw/s390x/pv.h
@@ -51,6 +51,10 @@ uint64_t kvm_s390_pv_dmp_get_size_cpu(void);
 uint64_t kvm_s390_pv_dmp_get_size_mem_state(void);
 uint64_t kvm_s390_pv_dmp_get_size_completion_data(void);
 bool kvm_s390_pv_info_basic_valid(void);
+int kvm_s390_dump_init(void);
+int kvm_s390_dump_cpu(S390CPU *cpu, void *buff);
+int kvm_s390_dump_mem_state(uint64_t addr, size_t len, void *dest);
+int kvm_s390_dump_completion_data(void *buff);
 #else /* CONFIG_KVM */
 static inline bool s390_is_pv(void) { return false; }
 static inline int s390_pv_query_info(void) { return 0; }
@@ -66,6 +70,11 @@ static inline uint64_t kvm_s390_pv_dmp_get_size_cpu(void) { return 0; }
 static inline uint64_t kvm_s390_pv_dmp_get_size_mem_state(void) { return 0; }
 static inline uint64_t kvm_s390_pv_dmp_get_size_completion_data(void) { return 0; }
 static inline bool kvm_s390_pv_info_basic_valid(void) { return false; }
+static inline int kvm_s390_dump_init(void) { return 0; }
+static inline int kvm_s390_dump_cpu(S390CPU *cpu, void *buff, size_t len) { return 0; }
+static inline int kvm_s390_dump_mem_state(uint64_t addr, size_t len,
+                                          void *dest) { return 0; }
+static inline int kvm_s390_dump_completion_data(void *buff) { return 0; }
 #endif /* CONFIG_KVM */

To fix build issue:

../target/s390x/arch_dump.c
../target/s390x/arch_dump.c: In function ‘s390x_write_elf64_pv’:
../target/s390x/arch_dump.c:195:5: error: too few arguments to
function ‘kvm_s390_dump_cpu’
195 | kvm_s390_dump_cpu(cpu, &note->contents.dynamic);
| ^~~~~~~~~~~~~~~~~
In file included from ../target/s390x/arch_dump.c:20:
/builds/qemu-project/qemu/include/hw/s390x/pv.h:74:19: note: declared here
74 | static inline int kvm_s390_dump_cpu(S390CPU *cpu, void *buff,
size_t len) { return 0; }
| ^~~~~~~~~~~~~~~~~

https://gitlab.com/qemu-project/qemu/-/jobs/3218295751

Can you ack squashing this to this patch?:

diff --git a/include/hw/s390x/pv.h b/include/hw/s390x/pv.h
index 3164006674..9360aa1091 100644
--- a/include/hw/s390x/pv.h
+++ b/include/hw/s390x/pv.h
@@ -71,7 +71,7 @@ static inline uint64_t kvm_s390_pv_dmp_get_size_mem_state(void) { return 0; }
 static inline uint64_t kvm_s390_pv_dmp_get_size_completion_data(void) { return 0; }
 static inline bool kvm_s390_pv_info_basic_valid(void) { return false; }
 static inline int kvm_s390_dump_init(void) { return 0; }
-static inline int kvm_s390_dump_cpu(S390CPU *cpu, void *buff, size_t len) { return 0; }
+static inline int kvm_s390_dump_cpu(S390CPU *cpu, void *buff) { return 0; }
 static inline int kvm_s390_dump_mem_state(uint64_t addr, size_t len,
                                           void *dest) { return 0; }
 static inline int kvm_s390_dump_completion_data(void *buff) { return 0; }

 

thanks

 int s390_pv_kvm_init(ConfidentialGuestSupport *cgs, Error **errp);
--
2.34.1

--

Marc-André Lureau