[Qemu-devel] [PATCH 0/2] xen-hvm: Clean up error handling a bit

[Qemu-devel] [PATCH 0/2] xen-hvm: Clean up error handling a bit

[Markus Armbruster]

Compile-tested only.

Please have a close look at xen_ram_alloc() case RUN_STATE_INMIGRATE.
I didn't change it, because I don't understand it.  What does the
message mean?  Is it informational?  Should it be an error?
Programming error?

Markus Armbruster (2):
  xen-hvm: Clean up xen_hvm_init() error handling
  xen-hvm: Clean up xen_ram_alloc() error handling

 exec.c               |  8 ++++++-
 hw/i386/pc_piix.c    |  5 ++--
 hw/i386/pc_q35.c     |  5 ++--
 include/hw/xen/xen.h |  4 ++--
 xen-hvm-stub.c       |  6 ++---
 xen-hvm.c            | 68 +++++++++++++++++++++++++++-------------------------
 6 files changed, 52 insertions(+), 44 deletions(-)

-- 
2.4.3

[Qemu-devel] [PATCH 1/2] xen-hvm: Clean up xen_hvm_init() error handling

[Markus Armbruster]

xen_hvm_init() returns -1 without cleaning up on some errors (harmless
long as the caller exit()s on error), dies with hw_error() on others.
hw_error() isn't approprate here.  Clean up to exit() on all errors.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 hw/i386/pc_piix.c    |  5 ++---
 hw/i386/pc_q35.c     |  5 ++---
 include/hw/xen/xen.h |  2 +-
 xen-hvm-stub.c       |  3 +--
 xen-hvm.c            | 61 +++++++++++++++++++++++++++-------------------------
 5 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index df2b824..db0ae9c 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -121,9 +121,8 @@ static void pc_init1(MachineState *machine,
         pcms->below_4g_mem_size = machine->ram_size;
     }
 
-    if (xen_enabled() && xen_hvm_init(pcms, &ram_memory) != 0) {
-        fprintf(stderr, "xen hardware virtual machine initialisation failed\n");
-        exit(1);
+    if (xen_enabled()) {
+        xen_hvm_init(pcms, &ram_memory);
     }
 
     pc_cpus_init(pcms);
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 412b3cd..abbcbf9 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -111,9 +111,8 @@ static void pc_q35_init(MachineState *machine)
         pcms->below_4g_mem_size = machine->ram_size;
     }
 
-    if (xen_enabled() && xen_hvm_init(pcms, &ram_memory) != 0) {
-        fprintf(stderr, "xen hardware virtual machine initialisation failed\n");
-        exit(1);
+    if (xen_enabled()) {
+        xen_hvm_init(pcms, &ram_memory);
     }
 
     pc_cpus_init(pcms);
diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
index e90931a..d07bc99 100644
--- a/include/hw/xen/xen.h
+++ b/include/hw/xen/xen.h
@@ -39,7 +39,7 @@ qemu_irq *xen_interrupt_controller_init(void);
 void xenstore_store_pv_console_info(int i, struct CharDriverState *chr);
 
 #if defined(NEED_CPU_H) && !defined(CONFIG_USER_ONLY)
-int xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory);
+void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory);
 void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
                    struct MemoryRegion *mr);
 void xen_modified_memory(ram_addr_t start, ram_addr_t length);
diff --git a/xen-hvm-stub.c b/xen-hvm-stub.c
index 6a39425..7ff0602 100644
--- a/xen-hvm-stub.c
+++ b/xen-hvm-stub.c
@@ -47,9 +47,8 @@ void xen_modified_memory(ram_addr_t start, ram_addr_t length)
 {
 }
 
-int xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
+void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
 {
-    return 0;
 }
 
 void qmp_xen_set_global_dirty_log(bool enable, Error **errp)
diff --git a/xen-hvm.c b/xen-hvm.c
index 2a93390..cb7128c 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -17,6 +17,7 @@
 #include "qmp-commands.h"
 
 #include "sysemu/char.h"
+#include "qemu/error-report.h"
 #include "qemu/range.h"
 #include "sysemu/xen-mapcache.h"
 #include "trace.h"
@@ -1189,16 +1190,8 @@ static void xen_wakeup_notifier(Notifier *notifier, void *data)
     xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 0);
 }
 
-/* return 0 means OK, or -1 means critical issue -- will exit(1) */
-int xen_hvm_init(PCMachineState *pcms,
-                 MemoryRegion **ram_memory)
+void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
 {
-    /*
-     * FIXME Returns -1 without cleaning up on some errors (harmless
-     * as long as the caller exit()s on error), dies with hw_error()
-     * on others.  hw_error() isn't approprate here.  Should probably
-     * simply exit() on all errors.
-     */
     int i, rc;
     xen_pfn_t ioreq_pfn;
     xen_pfn_t bufioreq_pfn;
@@ -1210,19 +1203,19 @@ int xen_hvm_init(PCMachineState *pcms,
     state->xce_handle = xen_xc_evtchn_open(NULL, 0);
     if (state->xce_handle == XC_HANDLER_INITIAL_VALUE) {
         perror("xen: event channel open");
-        return -1;
+        goto err;
     }
 
     state->xenstore = xs_daemon_open();
     if (state->xenstore == NULL) {
         perror("xen: xenstore open");
-        return -1;
+        goto err;
     }
 
     rc = xen_create_ioreq_server(xen_xc, xen_domid, &state->ioservid);
     if (rc < 0) {
         perror("xen: ioreq server create");
-        return -1;
+        goto err;
     }
 
     state->exit.notify = xen_exit_notifier;
@@ -1238,8 +1231,9 @@ int xen_hvm_init(PCMachineState *pcms,
                                    &ioreq_pfn, &bufioreq_pfn,
                                    &bufioreq_evtchn);
     if (rc < 0) {
-        hw_error("failed to get ioreq server info: error %d handle=" XC_INTERFACE_FMT,
-                 errno, xen_xc);
+        error_report("failed to get ioreq server info: error %d handle=" XC_INTERFACE_FMT,
+                     errno, xen_xc);
+        goto err;
     }
 
     DPRINTF("shared page at pfn %lx\n", ioreq_pfn);
@@ -1249,8 +1243,9 @@ int xen_hvm_init(PCMachineState *pcms,
     state->shared_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
                                               PROT_READ|PROT_WRITE, ioreq_pfn);
     if (state->shared_page == NULL) {
-        hw_error("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
-                 errno, xen_xc);
+        error_report("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
+                     errno, xen_xc);
+        goto err;
     }
 
     rc = xen_get_vmport_regs_pfn(xen_xc, xen_domid, &ioreq_pfn);
@@ -1260,11 +1255,14 @@ int xen_hvm_init(PCMachineState *pcms,
             xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
                                  PROT_READ|PROT_WRITE, ioreq_pfn);
         if (state->shared_vmport_page == NULL) {
-            hw_error("map shared vmport IO page returned error %d handle="
-                     XC_INTERFACE_FMT, errno, xen_xc);
+            error_report("map shared vmport IO page returned error %d handle="
+                         XC_INTERFACE_FMT, errno, xen_xc);
+            goto err;
         }
     } else if (rc != -ENOSYS) {
-        hw_error("get vmport regs pfn returned error %d, rc=%d", errno, rc);
+        error_report("get vmport regs pfn returned error %d, rc=%d",
+                     errno, rc);
+        goto err;
     }
 
     state->buffered_io_page = xc_map_foreign_range(xen_xc, xen_domid,
@@ -1272,7 +1270,8 @@ int xen_hvm_init(PCMachineState *pcms,
                                                    PROT_READ|PROT_WRITE,
                                                    bufioreq_pfn);
     if (state->buffered_io_page == NULL) {
-        hw_error("map buffered IO page returned error %d", errno);
+        error_report("map buffered IO page returned error %d", errno);
+        goto err;
     }
 
     /* Note: cpus is empty at this point in init */
@@ -1280,8 +1279,9 @@ int xen_hvm_init(PCMachineState *pcms,
 
     rc = xen_set_ioreq_server_state(xen_xc, xen_domid, state->ioservid, true);
     if (rc < 0) {
-        hw_error("failed to enable ioreq server info: error %d handle=" XC_INTERFACE_FMT,
-                 errno, xen_xc);
+        error_report("failed to enable ioreq server info: error %d handle=" XC_INTERFACE_FMT,
+                     errno, xen_xc);
+        goto err;
     }
 
     state->ioreq_local_port = g_malloc0(max_cpus * sizeof (evtchn_port_t));
@@ -1291,8 +1291,8 @@ int xen_hvm_init(PCMachineState *pcms,
         rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
                                         xen_vcpu_eport(state->shared_page, i));
         if (rc == -1) {
-            fprintf(stderr, "shared evtchn %d bind error %d\n", i, errno);
-            return -1;
+            error_report("shared evtchn %d bind error %d", i, errno);
+            goto err;
         }
         state->ioreq_local_port[i] = rc;
     }
@@ -1300,8 +1300,8 @@ int xen_hvm_init(PCMachineState *pcms,
     rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
                                     bufioreq_evtchn);
     if (rc == -1) {
-        fprintf(stderr, "buffered evtchn bind error %d\n", errno);
-        return -1;
+        error_report("buffered evtchn bind error %d", errno);
+        goto err;
     }
     state->bufioreq_local_port = rc;
 
@@ -1324,15 +1324,18 @@ int xen_hvm_init(PCMachineState *pcms,
 
     /* Initialize backend core & drivers */
     if (xen_be_init() != 0) {
-        fprintf(stderr, "%s: xen backend core setup failed\n", __FUNCTION__);
-        return -1;
+        error_report("xen backend core setup failed");
+        goto err;
     }
     xen_be_register("console", &xen_console_ops);
     xen_be_register("vkbd", &xen_kbdmouse_ops);
     xen_be_register("qdisk", &xen_blkdev_ops);
     xen_read_physmap(state);
+    return;
 
-    return 0;
+err:
+    error_report("xen hardware virtual machine initialisation failed");
+    exit(1);
 }
 
 void destroy_hvm_domain(bool reboot)
-- 
2.4.3

[Qemu-devel] [PATCH 2/2] xen-hvm: Clean up xen_ram_alloc() error handling

[Markus Armbruster]

xen_ram_alloc() dies with hw_error() on error, even though its caller
ram_block_add() handles errors just fine.  Add an Error **errp
parameter and use it.

Leave case RUN_STATE_INMIGRATE alone, because that looks like some
kind of warning.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
---
 exec.c               | 8 +++++++-
 include/hw/xen/xen.h | 2 +-
 xen-hvm-stub.c       | 3 ++-
 xen-hvm.c            | 7 ++++---
 4 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/exec.c b/exec.c
index 7f0ce42..c268c36 100644
--- a/exec.c
+++ b/exec.c
@@ -1474,6 +1474,7 @@ static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp)
     RAMBlock *block;
     RAMBlock *last_block = NULL;
     ram_addr_t old_ram_size, new_ram_size;
+    Error *err = NULL;
 
     old_ram_size = last_ram_offset() >> TARGET_PAGE_BITS;
 
@@ -1483,7 +1484,12 @@ static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp)
     if (!new_block->host) {
         if (xen_enabled()) {
             xen_ram_alloc(new_block->offset, new_block->max_length,
-                          new_block->mr);
+                          new_block->mr, &err);
+            if (err) {
+                error_propagate(errp, err);
+                qemu_mutex_unlock_ramlist();
+                return -1;
+            }
         } else {
             new_block->host = phys_mem_alloc(new_block->max_length,
                                              &new_block->mr->align);
diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
index d07bc99..1b81b4b 100644
--- a/include/hw/xen/xen.h
+++ b/include/hw/xen/xen.h
@@ -41,7 +41,7 @@ void xenstore_store_pv_console_info(int i, struct CharDriverState *chr);
 #if defined(NEED_CPU_H) && !defined(CONFIG_USER_ONLY)
 void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory);
 void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
-                   struct MemoryRegion *mr);
+                   struct MemoryRegion *mr, Error **errp);
 void xen_modified_memory(ram_addr_t start, ram_addr_t length);
 #endif
 
diff --git a/xen-hvm-stub.c b/xen-hvm-stub.c
index 7ff0602..b958367 100644
--- a/xen-hvm-stub.c
+++ b/xen-hvm-stub.c
@@ -30,7 +30,8 @@ void xen_hvm_inject_msi(uint64_t addr, uint32_t data)
 {
 }
 
-void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr)
+void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr,
+                   Error **errp)
 {
 }
 
diff --git a/xen-hvm.c b/xen-hvm.c
index cb7128c..a9085a8 100644
--- a/xen-hvm.c
+++ b/xen-hvm.c
@@ -239,9 +239,9 @@ static void xen_ram_init(PCMachineState *pcms,
     }
 }
 
-void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr)
+void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr,
+                   Error **errp)
 {
-    /* FIXME caller ram_block_add() wants error_setg() on failure */
     unsigned long nr_pfn;
     xen_pfn_t *pfn_list;
     int i;
@@ -268,7 +268,8 @@ void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr)
     }
 
     if (xc_domain_populate_physmap_exact(xen_xc, xen_domid, nr_pfn, 0, 0, pfn_list)) {
-        hw_error("xen: failed to populate ram at " RAM_ADDR_FMT, ram_addr);
+        error_setg(errp, "xen: failed to populate ram at " RAM_ADDR_FMT,
+                   ram_addr);
     }
 
     g_free(pfn_list);
-- 
2.4.3

Re: [Qemu-devel] [PATCH 1/2] xen-hvm: Clean up xen_hvm_init() error handling

[Stefano Stabellini]

On Thu, 14 Jan 2016, Markus Armbruster wrote:
> xen_hvm_init() returns -1 without cleaning up on some errors (harmless
> long as the caller exit()s on error), dies with hw_error() on others.
> hw_error() isn't approprate here.  Clean up to exit() on all errors.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>

Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>


>  hw/i386/pc_piix.c    |  5 ++---
>  hw/i386/pc_q35.c     |  5 ++---
>  include/hw/xen/xen.h |  2 +-
>  xen-hvm-stub.c       |  3 +--
>  xen-hvm.c            | 61 +++++++++++++++++++++++++++-------------------------
>  5 files changed, 38 insertions(+), 38 deletions(-)
> 
> diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
> index df2b824..db0ae9c 100644
> --- a/hw/i386/pc_piix.c
> +++ b/hw/i386/pc_piix.c
> @@ -121,9 +121,8 @@ static void pc_init1(MachineState *machine,
>          pcms->below_4g_mem_size = machine->ram_size;
>      }
>  
> -    if (xen_enabled() && xen_hvm_init(pcms, &ram_memory) != 0) {
> -        fprintf(stderr, "xen hardware virtual machine initialisation failed\n");
> -        exit(1);
> +    if (xen_enabled()) {
> +        xen_hvm_init(pcms, &ram_memory);
>      }
>  
>      pc_cpus_init(pcms);
> diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
> index 412b3cd..abbcbf9 100644
> --- a/hw/i386/pc_q35.c
> +++ b/hw/i386/pc_q35.c
> @@ -111,9 +111,8 @@ static void pc_q35_init(MachineState *machine)
>          pcms->below_4g_mem_size = machine->ram_size;
>      }
>  
> -    if (xen_enabled() && xen_hvm_init(pcms, &ram_memory) != 0) {
> -        fprintf(stderr, "xen hardware virtual machine initialisation failed\n");
> -        exit(1);
> +    if (xen_enabled()) {
> +        xen_hvm_init(pcms, &ram_memory);
>      }
>  
>      pc_cpus_init(pcms);
> diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
> index e90931a..d07bc99 100644
> --- a/include/hw/xen/xen.h
> +++ b/include/hw/xen/xen.h
> @@ -39,7 +39,7 @@ qemu_irq *xen_interrupt_controller_init(void);
>  void xenstore_store_pv_console_info(int i, struct CharDriverState *chr);
>  
>  #if defined(NEED_CPU_H) && !defined(CONFIG_USER_ONLY)
> -int xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory);
> +void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory);
>  void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
>                     struct MemoryRegion *mr);
>  void xen_modified_memory(ram_addr_t start, ram_addr_t length);
> diff --git a/xen-hvm-stub.c b/xen-hvm-stub.c
> index 6a39425..7ff0602 100644
> --- a/xen-hvm-stub.c
> +++ b/xen-hvm-stub.c
> @@ -47,9 +47,8 @@ void xen_modified_memory(ram_addr_t start, ram_addr_t length)
>  {
>  }
>  
> -int xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
> +void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
>  {
> -    return 0;
>  }
>  
>  void qmp_xen_set_global_dirty_log(bool enable, Error **errp)
> diff --git a/xen-hvm.c b/xen-hvm.c
> index 2a93390..cb7128c 100644
> --- a/xen-hvm.c
> +++ b/xen-hvm.c
> @@ -17,6 +17,7 @@
>  #include "qmp-commands.h"
>  
>  #include "sysemu/char.h"
> +#include "qemu/error-report.h"
>  #include "qemu/range.h"
>  #include "sysemu/xen-mapcache.h"
>  #include "trace.h"
> @@ -1189,16 +1190,8 @@ static void xen_wakeup_notifier(Notifier *notifier, void *data)
>      xc_set_hvm_param(xen_xc, xen_domid, HVM_PARAM_ACPI_S_STATE, 0);
>  }
>  
> -/* return 0 means OK, or -1 means critical issue -- will exit(1) */
> -int xen_hvm_init(PCMachineState *pcms,
> -                 MemoryRegion **ram_memory)
> +void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory)
>  {
> -    /*
> -     * FIXME Returns -1 without cleaning up on some errors (harmless
> -     * as long as the caller exit()s on error), dies with hw_error()
> -     * on others.  hw_error() isn't approprate here.  Should probably
> -     * simply exit() on all errors.
> -     */
>      int i, rc;
>      xen_pfn_t ioreq_pfn;
>      xen_pfn_t bufioreq_pfn;
> @@ -1210,19 +1203,19 @@ int xen_hvm_init(PCMachineState *pcms,
>      state->xce_handle = xen_xc_evtchn_open(NULL, 0);
>      if (state->xce_handle == XC_HANDLER_INITIAL_VALUE) {
>          perror("xen: event channel open");
> -        return -1;
> +        goto err;
>      }
>  
>      state->xenstore = xs_daemon_open();
>      if (state->xenstore == NULL) {
>          perror("xen: xenstore open");
> -        return -1;
> +        goto err;
>      }
>  
>      rc = xen_create_ioreq_server(xen_xc, xen_domid, &state->ioservid);
>      if (rc < 0) {
>          perror("xen: ioreq server create");
> -        return -1;
> +        goto err;
>      }
>  
>      state->exit.notify = xen_exit_notifier;
> @@ -1238,8 +1231,9 @@ int xen_hvm_init(PCMachineState *pcms,
>                                     &ioreq_pfn, &bufioreq_pfn,
>                                     &bufioreq_evtchn);
>      if (rc < 0) {
> -        hw_error("failed to get ioreq server info: error %d handle=" XC_INTERFACE_FMT,
> -                 errno, xen_xc);
> +        error_report("failed to get ioreq server info: error %d handle=" XC_INTERFACE_FMT,
> +                     errno, xen_xc);
> +        goto err;
>      }
>  
>      DPRINTF("shared page at pfn %lx\n", ioreq_pfn);
> @@ -1249,8 +1243,9 @@ int xen_hvm_init(PCMachineState *pcms,
>      state->shared_page = xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
>                                                PROT_READ|PROT_WRITE, ioreq_pfn);
>      if (state->shared_page == NULL) {
> -        hw_error("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
> -                 errno, xen_xc);
> +        error_report("map shared IO page returned error %d handle=" XC_INTERFACE_FMT,
> +                     errno, xen_xc);
> +        goto err;
>      }
>  
>      rc = xen_get_vmport_regs_pfn(xen_xc, xen_domid, &ioreq_pfn);
> @@ -1260,11 +1255,14 @@ int xen_hvm_init(PCMachineState *pcms,
>              xc_map_foreign_range(xen_xc, xen_domid, XC_PAGE_SIZE,
>                                   PROT_READ|PROT_WRITE, ioreq_pfn);
>          if (state->shared_vmport_page == NULL) {
> -            hw_error("map shared vmport IO page returned error %d handle="
> -                     XC_INTERFACE_FMT, errno, xen_xc);
> +            error_report("map shared vmport IO page returned error %d handle="
> +                         XC_INTERFACE_FMT, errno, xen_xc);
> +            goto err;
>          }
>      } else if (rc != -ENOSYS) {
> -        hw_error("get vmport regs pfn returned error %d, rc=%d", errno, rc);
> +        error_report("get vmport regs pfn returned error %d, rc=%d",
> +                     errno, rc);
> +        goto err;
>      }
>  
>      state->buffered_io_page = xc_map_foreign_range(xen_xc, xen_domid,
> @@ -1272,7 +1270,8 @@ int xen_hvm_init(PCMachineState *pcms,
>                                                     PROT_READ|PROT_WRITE,
>                                                     bufioreq_pfn);
>      if (state->buffered_io_page == NULL) {
> -        hw_error("map buffered IO page returned error %d", errno);
> +        error_report("map buffered IO page returned error %d", errno);
> +        goto err;
>      }
>  
>      /* Note: cpus is empty at this point in init */
> @@ -1280,8 +1279,9 @@ int xen_hvm_init(PCMachineState *pcms,
>  
>      rc = xen_set_ioreq_server_state(xen_xc, xen_domid, state->ioservid, true);
>      if (rc < 0) {
> -        hw_error("failed to enable ioreq server info: error %d handle=" XC_INTERFACE_FMT,
> -                 errno, xen_xc);
> +        error_report("failed to enable ioreq server info: error %d handle=" XC_INTERFACE_FMT,
> +                     errno, xen_xc);
> +        goto err;
>      }
>  
>      state->ioreq_local_port = g_malloc0(max_cpus * sizeof (evtchn_port_t));
> @@ -1291,8 +1291,8 @@ int xen_hvm_init(PCMachineState *pcms,
>          rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
>                                          xen_vcpu_eport(state->shared_page, i));
>          if (rc == -1) {
> -            fprintf(stderr, "shared evtchn %d bind error %d\n", i, errno);
> -            return -1;
> +            error_report("shared evtchn %d bind error %d", i, errno);
> +            goto err;
>          }
>          state->ioreq_local_port[i] = rc;
>      }
> @@ -1300,8 +1300,8 @@ int xen_hvm_init(PCMachineState *pcms,
>      rc = xc_evtchn_bind_interdomain(state->xce_handle, xen_domid,
>                                      bufioreq_evtchn);
>      if (rc == -1) {
> -        fprintf(stderr, "buffered evtchn bind error %d\n", errno);
> -        return -1;
> +        error_report("buffered evtchn bind error %d", errno);
> +        goto err;
>      }
>      state->bufioreq_local_port = rc;
>  
> @@ -1324,15 +1324,18 @@ int xen_hvm_init(PCMachineState *pcms,
>  
>      /* Initialize backend core & drivers */
>      if (xen_be_init() != 0) {
> -        fprintf(stderr, "%s: xen backend core setup failed\n", __FUNCTION__);
> -        return -1;
> +        error_report("xen backend core setup failed");
> +        goto err;
>      }
>      xen_be_register("console", &xen_console_ops);
>      xen_be_register("vkbd", &xen_kbdmouse_ops);
>      xen_be_register("qdisk", &xen_blkdev_ops);
>      xen_read_physmap(state);
> +    return;
>  
> -    return 0;
> +err:
> +    error_report("xen hardware virtual machine initialisation failed");
> +    exit(1);
>  }
>  
>  void destroy_hvm_domain(bool reboot)
> -- 
> 2.4.3
> 

Re: [Qemu-devel] [PATCH 2/2] xen-hvm: Clean up xen_ram_alloc() error handling

[Stefano Stabellini]

On Thu, 14 Jan 2016, Markus Armbruster wrote:
> xen_ram_alloc() dies with hw_error() on error, even though its caller
> ram_block_add() handles errors just fine.  Add an Error **errp
> parameter and use it.
> 
> Leave case RUN_STATE_INMIGRATE alone, because that looks like some
> kind of warning.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>

Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

I am happy to queue both patches up in my next branch.


>  exec.c               | 8 +++++++-
>  include/hw/xen/xen.h | 2 +-
>  xen-hvm-stub.c       | 3 ++-
>  xen-hvm.c            | 7 ++++---
>  4 files changed, 14 insertions(+), 6 deletions(-)
> 
> diff --git a/exec.c b/exec.c
> index 7f0ce42..c268c36 100644
> --- a/exec.c
> +++ b/exec.c
> @@ -1474,6 +1474,7 @@ static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp)
>      RAMBlock *block;
>      RAMBlock *last_block = NULL;
>      ram_addr_t old_ram_size, new_ram_size;
> +    Error *err = NULL;
>  
>      old_ram_size = last_ram_offset() >> TARGET_PAGE_BITS;
>  
> @@ -1483,7 +1484,12 @@ static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp)
>      if (!new_block->host) {
>          if (xen_enabled()) {
>              xen_ram_alloc(new_block->offset, new_block->max_length,
> -                          new_block->mr);
> +                          new_block->mr, &err);
> +            if (err) {
> +                error_propagate(errp, err);
> +                qemu_mutex_unlock_ramlist();
> +                return -1;
> +            }
>          } else {
>              new_block->host = phys_mem_alloc(new_block->max_length,
>                                               &new_block->mr->align);
> diff --git a/include/hw/xen/xen.h b/include/hw/xen/xen.h
> index d07bc99..1b81b4b 100644
> --- a/include/hw/xen/xen.h
> +++ b/include/hw/xen/xen.h
> @@ -41,7 +41,7 @@ void xenstore_store_pv_console_info(int i, struct CharDriverState *chr);
>  #if defined(NEED_CPU_H) && !defined(CONFIG_USER_ONLY)
>  void xen_hvm_init(PCMachineState *pcms, MemoryRegion **ram_memory);
>  void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size,
> -                   struct MemoryRegion *mr);
> +                   struct MemoryRegion *mr, Error **errp);
>  void xen_modified_memory(ram_addr_t start, ram_addr_t length);
>  #endif
>  
> diff --git a/xen-hvm-stub.c b/xen-hvm-stub.c
> index 7ff0602..b958367 100644
> --- a/xen-hvm-stub.c
> +++ b/xen-hvm-stub.c
> @@ -30,7 +30,8 @@ void xen_hvm_inject_msi(uint64_t addr, uint32_t data)
>  {
>  }
>  
> -void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr)
> +void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr,
> +                   Error **errp)
>  {
>  }
>  
> diff --git a/xen-hvm.c b/xen-hvm.c
> index cb7128c..a9085a8 100644
> --- a/xen-hvm.c
> +++ b/xen-hvm.c
> @@ -239,9 +239,9 @@ static void xen_ram_init(PCMachineState *pcms,
>      }
>  }
>  
> -void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr)
> +void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr,
> +                   Error **errp)
>  {
> -    /* FIXME caller ram_block_add() wants error_setg() on failure */
>      unsigned long nr_pfn;
>      xen_pfn_t *pfn_list;
>      int i;
> @@ -268,7 +268,8 @@ void xen_ram_alloc(ram_addr_t ram_addr, ram_addr_t size, MemoryRegion *mr)
>      }
>  
>      if (xc_domain_populate_physmap_exact(xen_xc, xen_domid, nr_pfn, 0, 0, pfn_list)) {
> -        hw_error("xen: failed to populate ram at " RAM_ADDR_FMT, ram_addr);
> +        error_setg(errp, "xen: failed to populate ram at " RAM_ADDR_FMT,
> +                   ram_addr);
>      }
>  
>      g_free(pfn_list);
> -- 
> 2.4.3
> 

Re: [Qemu-devel] [PATCH 2/2] xen-hvm: Clean up xen_ram_alloc() error handling

[Markus Armbruster]

Stefano Stabellini <stefano.stabellini@eu.citrix.com> writes:

> On Thu, 14 Jan 2016, Markus Armbruster wrote:
>> xen_ram_alloc() dies with hw_error() on error, even though its caller
>> ram_block_add() handles errors just fine.  Add an Error **errp
>> parameter and use it.
>> 
>> Leave case RUN_STATE_INMIGRATE alone, because that looks like some
>> kind of warning.

Did you double-check this is okay?

>> Signed-off-by: Markus Armbruster <armbru@redhat.com>
>
> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
>
> I am happy to queue both patches up in my next branch.

Please do, thanks!

Re: [Qemu-devel] [PATCH 2/2] xen-hvm: Clean up xen_ram_alloc() error handling

[Stefano Stabellini]

On Fri, 15 Jan 2016, Markus Armbruster wrote:
> Stefano Stabellini <stefano.stabellini@eu.citrix.com> writes:
> 
> > On Thu, 14 Jan 2016, Markus Armbruster wrote:
> >> xen_ram_alloc() dies with hw_error() on error, even though its caller
> >> ram_block_add() handles errors just fine.  Add an Error **errp
> >> parameter and use it.
> >> 
> >> Leave case RUN_STATE_INMIGRATE alone, because that looks like some
> >> kind of warning.
> 
> Did you double-check this is okay?

Yes, that's right: it is more of a debug message than a warning. Memory
is migrated by Xen, rather than by QEMU, so RUN_STATE_INMIGRATE we avoid
allocating any ram.


> >> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> >
> > Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> >
> > I am happy to queue both patches up in my next branch.
> 
> Please do, thanks!
>