[Qemu-devel] [PULL 0/5] Bugfixes for 2.3.0-rc2

[Qemu-devel] [PULL 0/5] Bugfixes for 2.3.0-rc2

[Paolo Bonzini]

The following changes since commit 033a20359aaf93f4d8aa2be12558901e8e028baa:

  Merge remote-tracking branch 'remotes/afaerber/tags/qom-devices-for-peter' into staging (2015-03-31 12:12:23 +0100)

are available in the git repository at:

  git://github.com/bonzini/qemu.git tags/for-upstream

for you to fetch changes up to 4025446f0ac6213335c22ec43f3c3d8362ce7286:

  Revert "exec: Respect as_tranlsate_internal length clamp" (2015-04-01 10:06:38 +0200)

----------------------------------------------------------------
Fix for object_del of in-use memory, pvpanic
regression, PPC regression and bogus error message with
Oxygen theme.

----------------------------------------------------------------
Igor Mammedov (1):
      pc: acpi: fix pvpanic regression

Lin Ma (2):
      qom: Add can_be_deleted callback to UserCreatableClass
      hostmem: Prevent removing an in-use memory backend

Paolo Bonzini (2):
      rcu: do not create thread in pthread_atfork callback
      Revert "exec: Respect as_tranlsate_internal length clamp"

 backends/hostmem.c              | 14 ++++++++++++++
 exec.c                          |  6 ++++--
 hw/i386/acpi-build.c            |  2 +-
 include/qemu/rcu.h              |  1 +
 include/qom/object_interfaces.h | 13 +++++++++++++
 linux-user/syscall.c            |  1 +
 os-posix.c                      |  2 ++
 qmp.c                           |  5 +++++
 qom/object_interfaces.c         | 12 ++++++++++++
 util/rcu.c                      |  7 +++----
 10 files changed, 56 insertions(+), 7 deletions(-)
-- 
2.3.4

[Qemu-devel] [PULL 1/5] qom: Add can_be_deleted callback to UserCreatableClass

[Paolo Bonzini]

From: Lin Ma <lma@suse.com>

If backends implement the can_be_deleted and it returns false,
Then the qmp_object_del won't delete the given backends.

Signed-off-by: Lin Ma <lma@suse.com>
Message-Id: <1427704589-7688-2-git-send-email-lma@suse.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 include/qom/object_interfaces.h | 13 +++++++++++++
 qmp.c                           |  5 +++++
 qom/object_interfaces.c         | 12 ++++++++++++
 3 files changed, 30 insertions(+)

diff --git a/include/qom/object_interfaces.h b/include/qom/object_interfaces.h
index b792283..283ae0d 100644
--- a/include/qom/object_interfaces.h
+++ b/include/qom/object_interfaces.h
@@ -25,6 +25,8 @@ typedef struct UserCreatable {
  * UserCreatableClass:
  * @parent_class: the base class
  * @complete: callback to be called after @obj's properties are set.
+ * @can_be_deleted: callback to be called before an object is removed
+ * to check if @obj can be removed safely.
  *
  * Interface is designed to work with -object/object-add/object_add
  * commands.
@@ -47,6 +49,7 @@ typedef struct UserCreatableClass {
 
     /* <public> */
     void (*complete)(UserCreatable *uc, Error **errp);
+    bool (*can_be_deleted)(UserCreatable *uc, Error **errp);
 } UserCreatableClass;
 
 /**
@@ -59,4 +62,14 @@ typedef struct UserCreatableClass {
  * nothing.
  */
 void user_creatable_complete(Object *obj, Error **errp);
+
+/**
+ * user_creatable_can_be_deleted:
+ * @uc: the object whose can_be_deleted() method is called if implemented
+ * @errp: if an error occurs, a pointer to an area to store the error
+ *
+ * Wrapper to call can_be_deleted() method if one of types it's inherited
+ * from implements USER_CREATABLE interface.
+ */
+bool user_creatable_can_be_deleted(UserCreatable *uc, Error **errp);
 #endif
diff --git a/qmp.c b/qmp.c
index c479e77..e6c7050 100644
--- a/qmp.c
+++ b/qmp.c
@@ -711,6 +711,11 @@ void qmp_object_del(const char *id, Error **errp)
         error_setg(errp, "object id not found");
         return;
     }
+
+    if (!user_creatable_can_be_deleted(USER_CREATABLE(obj), errp)) {
+        error_setg(errp, "%s is in use, can not be deleted", id);
+        return;
+    }
     object_unparent(obj);
 }
 
diff --git a/qom/object_interfaces.c b/qom/object_interfaces.c
index 6360818..a66cd60 100644
--- a/qom/object_interfaces.c
+++ b/qom/object_interfaces.c
@@ -18,6 +18,18 @@ void user_creatable_complete(Object *obj, Error **errp)
     }
 }
 
+bool user_creatable_can_be_deleted(UserCreatable *uc, Error **errp)
+{
+
+    UserCreatableClass *ucc = USER_CREATABLE_GET_CLASS(uc);
+
+    if (ucc->can_be_deleted) {
+        return ucc->can_be_deleted(uc, errp);
+    } else {
+        return true;
+    }
+}
+
 static void register_types(void)
 {
     static const TypeInfo uc_interface_info = {
-- 
2.3.4

[Qemu-devel] [PULL 2/5] hostmem: Prevent removing an in-use memory backend

[Paolo Bonzini]

From: Lin Ma <lma@suse.com>

showing a memory device whose memdev is removed leads an assert:

(qemu) object_add memory-backend-ram,id=ram0,size=128M
(qemu) device_add pc-dimm,id=d0,memdev=ram0
(qemu) object_del ram0
(qemu) info memory-devices
**
ERROR:qom/object.c:1274:object_get_canonical_path_component:\
                            assertion failed: (obj->parent != NULL)
Aborted

The patch prevents removing an in-use mem backend and error out.

Signed-off-by: Lin Ma <lma@suse.com>
Message-Id: <1427704589-7688-3-git-send-email-lma@suse.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 backends/hostmem.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/backends/hostmem.c b/backends/hostmem.c
index 99e8f99..b7b6cf8 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -335,12 +335,26 @@ host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
     }
 }
 
+static bool
+host_memory_backend_can_be_deleted(UserCreatable *uc, Error **errp)
+{
+    MemoryRegion *mr;
+
+    mr = host_memory_backend_get_memory(MEMORY_BACKEND(uc), errp);
+    if (memory_region_is_mapped(mr)) {
+        return false;
+    } else {
+        return true;
+    }
+}
+
 static void
 host_memory_backend_class_init(ObjectClass *oc, void *data)
 {
     UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
 
     ucc->complete = host_memory_backend_memory_complete;
+    ucc->can_be_deleted = host_memory_backend_can_be_deleted;
 }
 
 static const TypeInfo host_memory_backend_info = {
-- 
2.3.4

[Qemu-devel] [PULL 3/5] pc: acpi: fix pvpanic regression

[Paolo Bonzini]

From: Igor Mammedov <imammedo@redhat.com>

Commit cd61cb2  pc: acpi-build: generate pvpanic device description dynamically

introduced regression changing pvpanic device HID from
QEMU0001 to QEMU0002.
Fix AML generated code so that pvpanic device
would keep its original HID. i.e. QEMU0001

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reported-by: Gal Hammer <ghammer@redhat.com>
Message-Id: <1427717907-25027-1-git-send-email-imammedo@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 hw/i386/acpi-build.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index d0a5c85..e761005 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -788,7 +788,7 @@ build_ssdt(GArray *table_data, GArray *linker,
         scope = aml_scope("\\_SB.PCI0.ISA");
 
         dev = aml_device("PEVR");
-        aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0002")));
+        aml_append(dev, aml_name_decl("_HID", aml_string("QEMU0001")));
 
         crs = aml_resource_template();
         aml_append(crs,
-- 
2.3.4

[Qemu-devel] [PULL 4/5] rcu: do not create thread in pthread_atfork callback

[Paolo Bonzini]

If QEMU forks after the CPU threads have been created, qemu_mutex_lock_iothread
will not be able to do qemu_cpu_kick_thread.  There is no solution other than
assuming that forks after the CPU threads have been created will end up in an
exec.  Forks before the CPU threads have been created (such as -daemonize)
have to call rcu_after_fork manually.

Notably, the oxygen theme for GTK+ forks and shows a "No such process" error
without this patch.

This patch can be reverted once the iothread loses the "kick the TCG thread"
magic.

User-mode emulation does not use the iothread, so it can also call
rcu_after_fork.

Reported by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 include/qemu/rcu.h   | 1 +
 linux-user/syscall.c | 1 +
 os-posix.c           | 2 ++
 util/rcu.c           | 7 +++----
 4 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/include/qemu/rcu.h b/include/qemu/rcu.h
index 506ab58..7df1e86 100644
--- a/include/qemu/rcu.h
+++ b/include/qemu/rcu.h
@@ -117,6 +117,7 @@ extern void synchronize_rcu(void);
  */
 extern void rcu_register_thread(void);
 extern void rcu_unregister_thread(void);
+extern void rcu_after_fork(void);
 
 struct rcu_head;
 typedef void RCUCBFunc(struct rcu_head *head);
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 4bd9543..1622ad6 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -4572,6 +4572,7 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp,
         ret = fork();
         if (ret == 0) {
             /* Child Process.  */
+            rcu_after_fork();
             cpu_clone_regs(env, newsp);
             fork_end(1);
             /* There is a race condition here.  The parent process could
diff --git a/os-posix.c b/os-posix.c
index ba091f1..e4da406 100644
--- a/os-posix.c
+++ b/os-posix.c
@@ -39,6 +39,7 @@
 #include "sysemu/sysemu.h"
 #include "net/slirp.h"
 #include "qemu-options.h"
+#include "qemu/rcu.h"
 
 #ifdef CONFIG_LINUX
 #include <sys/prctl.h>
@@ -247,6 +248,7 @@ void os_daemonize(void)
         signal(SIGTSTP, SIG_IGN);
         signal(SIGTTOU, SIG_IGN);
         signal(SIGTTIN, SIG_IGN);
+        rcu_after_fork();
     }
 }
 
diff --git a/util/rcu.c b/util/rcu.c
index 27802a4..7270151 100644
--- a/util/rcu.c
+++ b/util/rcu.c
@@ -311,19 +311,18 @@ static void rcu_init_unlock(void)
 {
     qemu_mutex_unlock(&rcu_gp_lock);
 }
+#endif
 
-static void rcu_init_child(void)
+void rcu_after_fork(void)
 {
-    qemu_mutex_unlock(&rcu_gp_lock);
     memset(&registry, 0, sizeof(registry));
     rcu_init_complete();
 }
-#endif
 
 static void __attribute__((__constructor__)) rcu_init(void)
 {
 #ifdef CONFIG_POSIX
-    pthread_atfork(rcu_init_lock, rcu_init_unlock, rcu_init_child);
+    pthread_atfork(rcu_init_lock, rcu_init_unlock, rcu_init_unlock);
 #endif
     rcu_init_complete();
 }
-- 
2.3.4

[Qemu-devel] [PULL 5/5] Revert "exec: Respect as_tranlsate_internal length clamp"

[Paolo Bonzini]

This reverts commit c3c1bb99d1c11978d9ce94d1bdcf0705378c1459.
It causes problems with boards that declare memory regions shorter
than the registers they contain.

Reported-by: Zoltan Balaton <balaton@eik.bme.hu>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 exec.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/exec.c b/exec.c
index 6d1e1e4..874ecfc 100644
--- a/exec.c
+++ b/exec.c
@@ -380,6 +380,7 @@ MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr,
     IOMMUTLBEntry iotlb;
     MemoryRegionSection *section;
     MemoryRegion *mr;
+    hwaddr len = *plen;
 
     rcu_read_lock();
     for (;;) {
@@ -394,7 +395,7 @@ MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr,
         iotlb = mr->iommu_ops->translate(mr, addr, is_write);
         addr = ((iotlb.translated_addr & ~iotlb.addr_mask)
                 | (addr & iotlb.addr_mask));
-        *plen = MIN(*plen, (addr | iotlb.addr_mask) - addr + 1);
+        len = MIN(len, (addr | iotlb.addr_mask) - addr + 1);
         if (!(iotlb.perm & (1 << is_write))) {
             mr = &io_mem_unassigned;
             break;
@@ -405,9 +406,10 @@ MemoryRegion *address_space_translate(AddressSpace *as, hwaddr addr,
 
     if (xen_enabled() && memory_access_is_direct(mr, is_write)) {
         hwaddr page = ((addr & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE) - addr;
-        *plen = MIN(page, *plen);
+        len = MIN(page, len);
     }
 
+    *plen = len;
     *xlat = addr;
     rcu_read_unlock();
     return mr;
-- 
2.3.4

Re: [Qemu-devel] [PULL 0/5] Bugfixes for 2.3.0-rc2

[Peter Maydell]

On 1 April 2015 at 11:29, Paolo Bonzini <pbonzini@redhat.com> wrote:
> The following changes since commit 033a20359aaf93f4d8aa2be12558901e8e028baa:
>
>   Merge remote-tracking branch 'remotes/afaerber/tags/qom-devices-for-peter' into staging (2015-03-31 12:12:23 +0100)
>
> are available in the git repository at:
>
>   git://github.com/bonzini/qemu.git tags/for-upstream
>
> for you to fetch changes up to 4025446f0ac6213335c22ec43f3c3d8362ce7286:
>
>   Revert "exec: Respect as_tranlsate_internal length clamp" (2015-04-01 10:06:38 +0200)
>
> ----------------------------------------------------------------
> Fix for object_del of in-use memory, pvpanic
> regression, PPC regression and bogus error message with
> Oxygen theme.
>

Applied, thanks.

-- PMM

Re: [Qemu-devel] [PULL 5/5] Revert "exec: Respect as_tranlsate_internal length clamp"

[Eric Blake]

[-- Attachment #1: Type: text/plain, Size: 420 bytes --]

On 04/01/2015 04:29 AM, Paolo Bonzini wrote:
> This reverts commit c3c1bb99d1c11978d9ce94d1bdcf0705378c1459.

Which means the typo in that commit message (tranlsate) is perpetuated
here too.  Cute.  Thankfully doesn't hurt anything other than bothering
OCD editors (does that mean I'm becoming one?  :)

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org


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Re: [Qemu-devel] [PULL 5/5] Revert "exec: Respect as_tranlsate_internal length clamp"

[Peter Maydell]

On 1 April 2015 at 13:27, Eric Blake <eblake@redhat.com> wrote:
> On 04/01/2015 04:29 AM, Paolo Bonzini wrote:
>> This reverts commit c3c1bb99d1c11978d9ce94d1bdcf0705378c1459.
>
> Which means the typo in that commit message (tranlsate) is perpetuated
> here too.  Cute.

Yep, but since we're quoting the earlier commit message
it's correct to include it typo and all. I guess Paolo
could have added a "(sic)" :-)

-- PMM

Re: [Qemu-devel] [PULL 5/5] Revert "exec: Respect as_tranlsate_internal length clamp"

[Paolo Bonzini]

On 01/04/2015 14:31, Peter Maydell wrote:
>> > On 04/01/2015 04:29 AM, Paolo Bonzini wrote:
>>> >> This reverts commit c3c1bb99d1c11978d9ce94d1bdcf0705378c1459.
>> >
>> > Which means the typo in that commit message (tranlsate) is perpetuated
>> > here too.  Cute.
> Yep, but since we're quoting the earlier commit message
> it's correct to include it typo and all. I guess Paolo
> could have added a "(sic)" :-)

I have fixed the typo in the version I staged for 2.4.  :)

Paolo