* [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() @ 2015-07-16 20:39 Eduardo Habkost 2015-07-16 21:02 ` Igor Mammedov 2015-07-17 7:21 ` Marcel Apfelbaum 0 siblings, 2 replies; 7+ messages in thread From: Eduardo Habkost @ 2015-07-16 20:39 UTC (permalink / raw) To: qemu-devel; +Cc: Paolo Bonzini, Marcel Apfelbaum This fixes the following crash, introduced by commit 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object memory-backend-ram,id=ram-node0,size=1024 [...] Program received signal SIGABRT, Aborted. (gdb) bt #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 #3 0x00007ffff2534522 in () at /lib64/libc.so.6 #4 0x00005555558bb80a in qemu_opt_get_bool_helper (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true, del=del@entry=false) at qemu/util/qemu-option.c:388 #5 0x00005555558bbb5a in qemu_opt_get_bool (opts=<optimized out>, name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) at qemu/util/qemu-option.c:398 #6 0x0000555555720a24 in host_memory_backend_init (obj=0x5555562ac970) at qemu/backends/hostmem.c:226 Instead of using qemu_opt_get_bool(), that didn't work with qemu_machine_opts for a long time, we can use the machine QOM properties directly. Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> --- backends/hostmem.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/backends/hostmem.c b/backends/hostmem.c index 61c1ac0..38a32ed 100644 --- a/backends/hostmem.c +++ b/backends/hostmem.c @@ -10,6 +10,7 @@ * See the COPYING file in the top-level directory. */ #include "sysemu/hostmem.h" +#include "hw/boards.h" #include "qapi/visitor.h" #include "qapi-types.h" #include "qapi-visit.h" @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object *obj) { HostMemoryBackend *backend = MEMORY_BACKEND(obj); - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), - "mem-merge", true); - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), - "dump-guest-core", true); + backend->merge = object_property_get_bool(OBJECT(current_machine), + "mem-merge", &error_abort); + backend->dump = object_property_get_bool(OBJECT(current_machine), + "dump-guest-core", &error_abort); backend->prealloc = mem_prealloc; object_property_add_bool(obj, "merge", -- 2.1.0 ^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() 2015-07-16 20:39 [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() Eduardo Habkost @ 2015-07-16 21:02 ` Igor Mammedov 2015-07-17 20:33 ` Eduardo Habkost 2015-07-17 7:21 ` Marcel Apfelbaum 1 sibling, 1 reply; 7+ messages in thread From: Igor Mammedov @ 2015-07-16 21:02 UTC (permalink / raw) To: Eduardo Habkost; +Cc: Paolo Bonzini, qemu-devel, Marcel Apfelbaum On Thu, 16 Jul 2015 17:39:17 -0300 Eduardo Habkost <ehabkost@redhat.com> wrote: > This fixes the following crash, introduced by commit > 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: > > $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object > memory-backend-ram,id=ram-node0,size=1024 [...] > Program received signal SIGABRT, Aborted. > (gdb) bt > #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 > #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 > #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 > #3 0x00007ffff2534522 in () at /lib64/libc.so.6 > #4 0x00005555558bb80a in qemu_opt_get_bool_helper > (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", > defval=defval@entry=true, del=del@entry=false) at > qemu/util/qemu-option.c:388 #5 0x00005555558bbb5a in > qemu_opt_get_bool (opts=<optimized out>, > name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) > at qemu/util/qemu-option.c:398 #6 0x0000555555720a24 in > host_memory_backend_init (obj=0x5555562ac970) at > qemu/backends/hostmem.c:226 > > Instead of using qemu_opt_get_bool(), that didn't work with > qemu_machine_opts for a long time, we can use the machine QOM > properties directly. > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > --- > backends/hostmem.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/backends/hostmem.c b/backends/hostmem.c > index 61c1ac0..38a32ed 100644 > --- a/backends/hostmem.c > +++ b/backends/hostmem.c > @@ -10,6 +10,7 @@ > * See the COPYING file in the top-level directory. > */ > #include "sysemu/hostmem.h" > +#include "hw/boards.h" > #include "qapi/visitor.h" > #include "qapi-types.h" > #include "qapi-visit.h" > @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object > *obj) { > HostMemoryBackend *backend = MEMORY_BACKEND(obj); > > - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), > - "mem-merge", true); > - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), > - "dump-guest-core", true); > + backend->merge = > object_property_get_bool(OBJECT(current_machine), maybe use qdev_get_machine() instead of OBJECT(current_machine) > + "mem-merge", > &error_abort); > + backend->dump = object_property_get_bool(OBJECT(current_machine), > + "dump-guest-core", > &error_abort); backend->prealloc = mem_prealloc; > > object_property_add_bool(obj, "merge", ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() 2015-07-16 21:02 ` Igor Mammedov @ 2015-07-17 20:33 ` Eduardo Habkost 2015-07-20 7:06 ` Igor Mammedov 0 siblings, 1 reply; 7+ messages in thread From: Eduardo Habkost @ 2015-07-17 20:33 UTC (permalink / raw) To: Igor Mammedov; +Cc: Paolo Bonzini, qemu-devel, Marcel Apfelbaum On Thu, Jul 16, 2015 at 11:02:14PM +0200, Igor Mammedov wrote: > On Thu, 16 Jul 2015 17:39:17 -0300 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > This fixes the following crash, introduced by commit > > 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: > > > > $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object > > memory-backend-ram,id=ram-node0,size=1024 [...] > > Program received signal SIGABRT, Aborted. > > (gdb) bt > > #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 > > #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 > > #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 > > #3 0x00007ffff2534522 in () at /lib64/libc.so.6 > > #4 0x00005555558bb80a in qemu_opt_get_bool_helper > > (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", > > defval=defval@entry=true, del=del@entry=false) at > > qemu/util/qemu-option.c:388 #5 0x00005555558bbb5a in > > qemu_opt_get_bool (opts=<optimized out>, > > name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) > > at qemu/util/qemu-option.c:398 #6 0x0000555555720a24 in > > host_memory_backend_init (obj=0x5555562ac970) at > > qemu/backends/hostmem.c:226 > > > > Instead of using qemu_opt_get_bool(), that didn't work with > > qemu_machine_opts for a long time, we can use the machine QOM > > properties directly. > > > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > > --- > > backends/hostmem.c | 9 +++++---- > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > diff --git a/backends/hostmem.c b/backends/hostmem.c > > index 61c1ac0..38a32ed 100644 > > --- a/backends/hostmem.c > > +++ b/backends/hostmem.c > > @@ -10,6 +10,7 @@ > > * See the COPYING file in the top-level directory. > > */ > > #include "sysemu/hostmem.h" > > +#include "hw/boards.h" > > #include "qapi/visitor.h" > > #include "qapi-types.h" > > #include "qapi-visit.h" > > @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object > > *obj) { > > HostMemoryBackend *backend = MEMORY_BACKEND(obj); > > > > - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), > > - "mem-merge", true); > > - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), > > - "dump-guest-core", true); > > + backend->merge = > > object_property_get_bool(OBJECT(current_machine), > maybe use qdev_get_machine() instead of OBJECT(current_machine) What are the advantages you see in the extra layers of indirection of qdev_get_machine()? (I am not against your proposal, but I would like to understand the point of qdev_get_machine() yet.) I'd prefer to use something that is guaranteed to be MachineState*, qdev_get_machine() returns Object*. I am even considering using current_machine->mem_merge and current_machine->dump_guest_core directly instead of object_property_get_bool(). That would mean extra compile-time checks, instead of runtime ones. -- Eduardo ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() 2015-07-17 20:33 ` Eduardo Habkost @ 2015-07-20 7:06 ` Igor Mammedov 2015-07-20 20:03 ` Eduardo Habkost 0 siblings, 1 reply; 7+ messages in thread From: Igor Mammedov @ 2015-07-20 7:06 UTC (permalink / raw) To: Eduardo Habkost; +Cc: Paolo Bonzini, qemu-devel, Marcel Apfelbaum On Fri, 17 Jul 2015 17:33:55 -0300 Eduardo Habkost <ehabkost@redhat.com> wrote: > On Thu, Jul 16, 2015 at 11:02:14PM +0200, Igor Mammedov wrote: > > On Thu, 16 Jul 2015 17:39:17 -0300 > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > This fixes the following crash, introduced by commit > > > 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: > > > > > > $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object > > > memory-backend-ram,id=ram-node0,size=1024 [...] > > > Program received signal SIGABRT, Aborted. > > > (gdb) bt > > > #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 > > > #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 > > > #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 > > > #3 0x00007ffff2534522 in () at /lib64/libc.so.6 > > > #4 0x00005555558bb80a in qemu_opt_get_bool_helper > > > (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", > > > defval=defval@entry=true, del=del@entry=false) at > > > qemu/util/qemu-option.c:388 #5 0x00005555558bbb5a in > > > qemu_opt_get_bool (opts=<optimized out>, > > > name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) > > > at qemu/util/qemu-option.c:398 #6 0x0000555555720a24 in > > > host_memory_backend_init (obj=0x5555562ac970) at > > > qemu/backends/hostmem.c:226 > > > > > > Instead of using qemu_opt_get_bool(), that didn't work with > > > qemu_machine_opts for a long time, we can use the machine QOM > > > properties directly. > > > > > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > > > --- > > > backends/hostmem.c | 9 +++++---- > > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > > > diff --git a/backends/hostmem.c b/backends/hostmem.c > > > index 61c1ac0..38a32ed 100644 > > > --- a/backends/hostmem.c > > > +++ b/backends/hostmem.c > > > @@ -10,6 +10,7 @@ > > > * See the COPYING file in the top-level directory. > > > */ > > > #include "sysemu/hostmem.h" > > > +#include "hw/boards.h" > > > #include "qapi/visitor.h" > > > #include "qapi-types.h" > > > #include "qapi-visit.h" > > > @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object > > > *obj) { > > > HostMemoryBackend *backend = MEMORY_BACKEND(obj); > > > > > > - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), > > > - "mem-merge", true); > > > - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), > > > - "dump-guest-core", true); > > > + backend->merge = > > > object_property_get_bool(OBJECT(current_machine), > > maybe use qdev_get_machine() instead of OBJECT(current_machine) > > What are the advantages you see in the extra layers of indirection of > qdev_get_machine()? (I am not against your proposal, but I would like to > understand the point of qdev_get_machine() yet.) current_machine might be NULL where as qdev_get_machine() always returns /machine object. > > I'd prefer to use something that is guaranteed to be MachineState*, > qdev_get_machine() returns Object*. I am even considering using > current_machine->mem_merge and current_machine->dump_guest_core directly > instead of object_property_get_bool(). That would mean extra > compile-time checks, instead of runtime ones. Check difference 'git grep qdev_get_machine' vs 'git grep current_machine'. I was under impression that policy was trying no to use globals unless one has to, and not introduce new usage in presence of other means to get object. ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() 2015-07-20 7:06 ` Igor Mammedov @ 2015-07-20 20:03 ` Eduardo Habkost 2015-07-20 20:06 ` Marcel Apfelbaum 0 siblings, 1 reply; 7+ messages in thread From: Eduardo Habkost @ 2015-07-20 20:03 UTC (permalink / raw) To: Igor Mammedov; +Cc: Paolo Bonzini, qemu-devel, Marcel Apfelbaum On Mon, Jul 20, 2015 at 09:06:28AM +0200, Igor Mammedov wrote: > On Fri, 17 Jul 2015 17:33:55 -0300 > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > On Thu, Jul 16, 2015 at 11:02:14PM +0200, Igor Mammedov wrote: > > > On Thu, 16 Jul 2015 17:39:17 -0300 > > > Eduardo Habkost <ehabkost@redhat.com> wrote: > > > > > > > This fixes the following crash, introduced by commit > > > > 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: > > > > > > > > $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object > > > > memory-backend-ram,id=ram-node0,size=1024 [...] > > > > Program received signal SIGABRT, Aborted. > > > > (gdb) bt > > > > #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 > > > > #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 > > > > #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 > > > > #3 0x00007ffff2534522 in () at /lib64/libc.so.6 > > > > #4 0x00005555558bb80a in qemu_opt_get_bool_helper > > > > (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", > > > > defval=defval@entry=true, del=del@entry=false) at > > > > qemu/util/qemu-option.c:388 #5 0x00005555558bbb5a in > > > > qemu_opt_get_bool (opts=<optimized out>, > > > > name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) > > > > at qemu/util/qemu-option.c:398 #6 0x0000555555720a24 in > > > > host_memory_backend_init (obj=0x5555562ac970) at > > > > qemu/backends/hostmem.c:226 > > > > > > > > Instead of using qemu_opt_get_bool(), that didn't work with > > > > qemu_machine_opts for a long time, we can use the machine QOM > > > > properties directly. > > > > > > > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > > > > --- > > > > backends/hostmem.c | 9 +++++---- > > > > 1 file changed, 5 insertions(+), 4 deletions(-) > > > > > > > > diff --git a/backends/hostmem.c b/backends/hostmem.c > > > > index 61c1ac0..38a32ed 100644 > > > > --- a/backends/hostmem.c > > > > +++ b/backends/hostmem.c > > > > @@ -10,6 +10,7 @@ > > > > * See the COPYING file in the top-level directory. > > > > */ > > > > #include "sysemu/hostmem.h" > > > > +#include "hw/boards.h" > > > > #include "qapi/visitor.h" > > > > #include "qapi-types.h" > > > > #include "qapi-visit.h" > > > > @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object > > > > *obj) { > > > > HostMemoryBackend *backend = MEMORY_BACKEND(obj); > > > > > > > > - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), > > > > - "mem-merge", true); > > > > - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), > > > > - "dump-guest-core", true); > > > > + backend->merge = > > > > object_property_get_bool(OBJECT(current_machine), > > > maybe use qdev_get_machine() instead of OBJECT(current_machine) > > > > What are the advantages you see in the extra layers of indirection of > > qdev_get_machine()? (I am not against your proposal, but I would like to > > understand the point of qdev_get_machine() yet.) > current_machine might be NULL where as qdev_get_machine() always returns > /machine object. In this case, I don't want "/machine" to be created as a generic container object by accident because it must be a MachineState object. If /machine is not initialized yet, that code should abort instead of trying to continue. But that can be solved by simply ensuring qdev_get_machine() is a TYPE_MACHINE object (see below). > > > > > I'd prefer to use something that is guaranteed to be MachineState*, > > qdev_get_machine() returns Object*. I am even considering using > > current_machine->mem_merge and current_machine->dump_guest_core directly > > instead of object_property_get_bool(). That would mean extra > > compile-time checks, instead of runtime ones. > Check difference 'git grep qdev_get_machine' vs 'git grep current_machine'. > I was under impression that policy was trying no to use globals unless one has to, > and not introduce new usage in presence of other means to get object. > I will send a new version using: MachineState *machine = MACHINE(qdev_get_machine()); backend->merge = machine_mem_merge(machine); backend->dump = machine_dump_guest_core(machine); Then we have no global variable, type safety, and no direct access to struct fields. -- Eduardo ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() 2015-07-20 20:03 ` Eduardo Habkost @ 2015-07-20 20:06 ` Marcel Apfelbaum 0 siblings, 0 replies; 7+ messages in thread From: Marcel Apfelbaum @ 2015-07-20 20:06 UTC (permalink / raw) To: Eduardo Habkost, Igor Mammedov Cc: Paolo Bonzini, qemu-devel, Marcel Apfelbaum On 07/20/2015 11:03 PM, Eduardo Habkost wrote: > On Mon, Jul 20, 2015 at 09:06:28AM +0200, Igor Mammedov wrote: >> On Fri, 17 Jul 2015 17:33:55 -0300 >> Eduardo Habkost <ehabkost@redhat.com> wrote: >> >>> On Thu, Jul 16, 2015 at 11:02:14PM +0200, Igor Mammedov wrote: >>>> On Thu, 16 Jul 2015 17:39:17 -0300 >>>> Eduardo Habkost <ehabkost@redhat.com> wrote: >>>> >>>>> This fixes the following crash, introduced by commit >>>>> 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: >>>>> >>>>> $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object >>>>> memory-backend-ram,id=ram-node0,size=1024 [...] >>>>> Program received signal SIGABRT, Aborted. >>>>> (gdb) bt >>>>> #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 >>>>> #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 >>>>> #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 >>>>> #3 0x00007ffff2534522 in () at /lib64/libc.so.6 >>>>> #4 0x00005555558bb80a in qemu_opt_get_bool_helper >>>>> (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", >>>>> defval=defval@entry=true, del=del@entry=false) at >>>>> qemu/util/qemu-option.c:388 #5 0x00005555558bbb5a in >>>>> qemu_opt_get_bool (opts=<optimized out>, >>>>> name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) >>>>> at qemu/util/qemu-option.c:398 #6 0x0000555555720a24 in >>>>> host_memory_backend_init (obj=0x5555562ac970) at >>>>> qemu/backends/hostmem.c:226 >>>>> >>>>> Instead of using qemu_opt_get_bool(), that didn't work with >>>>> qemu_machine_opts for a long time, we can use the machine QOM >>>>> properties directly. >>>>> >>>>> Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> >>>>> --- >>>>> backends/hostmem.c | 9 +++++---- >>>>> 1 file changed, 5 insertions(+), 4 deletions(-) >>>>> >>>>> diff --git a/backends/hostmem.c b/backends/hostmem.c >>>>> index 61c1ac0..38a32ed 100644 >>>>> --- a/backends/hostmem.c >>>>> +++ b/backends/hostmem.c >>>>> @@ -10,6 +10,7 @@ >>>>> * See the COPYING file in the top-level directory. >>>>> */ >>>>> #include "sysemu/hostmem.h" >>>>> +#include "hw/boards.h" >>>>> #include "qapi/visitor.h" >>>>> #include "qapi-types.h" >>>>> #include "qapi-visit.h" >>>>> @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object >>>>> *obj) { >>>>> HostMemoryBackend *backend = MEMORY_BACKEND(obj); >>>>> >>>>> - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), >>>>> - "mem-merge", true); >>>>> - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), >>>>> - "dump-guest-core", true); >>>>> + backend->merge = >>>>> object_property_get_bool(OBJECT(current_machine), >>>> maybe use qdev_get_machine() instead of OBJECT(current_machine) >>> >>> What are the advantages you see in the extra layers of indirection of >>> qdev_get_machine()? (I am not against your proposal, but I would like to >>> understand the point of qdev_get_machine() yet.) >> current_machine might be NULL where as qdev_get_machine() always returns >> /machine object. > > In this case, I don't want "/machine" to be created as a generic > container object by accident because it must be a MachineState object. > If /machine is not initialized yet, that code should abort instead of > trying to continue. > > But that can be solved by simply ensuring qdev_get_machine() is a > TYPE_MACHINE object (see below). > >> >>> >>> I'd prefer to use something that is guaranteed to be MachineState*, >>> qdev_get_machine() returns Object*. I am even considering using >>> current_machine->mem_merge and current_machine->dump_guest_core directly >>> instead of object_property_get_bool(). That would mean extra >>> compile-time checks, instead of runtime ones. >> Check difference 'git grep qdev_get_machine' vs 'git grep current_machine'. >> I was under impression that policy was trying no to use globals unless one has to, >> and not introduce new usage in presence of other means to get object. >> > > I will send a new version using: > > MachineState *machine = MACHINE(qdev_get_machine()); > backend->merge = machine_mem_merge(machine); > backend->dump = machine_dump_guest_core(machine); > > Then we have no global variable, type safety, and no direct access to > struct fields. +1 I am considering retiring curent_machine global variable for 2.5. Thanks, Marcel > ^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() 2015-07-16 20:39 [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() Eduardo Habkost 2015-07-16 21:02 ` Igor Mammedov @ 2015-07-17 7:21 ` Marcel Apfelbaum 1 sibling, 0 replies; 7+ messages in thread From: Marcel Apfelbaum @ 2015-07-17 7:21 UTC (permalink / raw) To: Eduardo Habkost, qemu-devel; +Cc: Paolo Bonzini, Marcel Apfelbaum On 07/16/2015 11:39 PM, Eduardo Habkost wrote: > This fixes the following crash, introduced by commit > 49d2e648e8087d154d8bf8b91f27c8e05e79d5a6: > > $ gdb --args qemu-system-x86_64 -machine pc,mem-merge=off -object memory-backend-ram,id=ram-node0,size=1024 > [...] > Program received signal SIGABRT, Aborted. > (gdb) bt > #0 0x00007ffff253b8c7 in raise () at /lib64/libc.so.6 > #1 0x00007ffff253d52a in abort () at /lib64/libc.so.6 > #2 0x00007ffff253446d in __assert_fail_base () at /lib64/libc.so.6 > #3 0x00007ffff2534522 in () at /lib64/libc.so.6 > #4 0x00005555558bb80a in qemu_opt_get_bool_helper (opts=0x55555621b650, name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true, del=del@entry=false) at qemu/util/qemu-option.c:388 > #5 0x00005555558bbb5a in qemu_opt_get_bool (opts=<optimized out>, name=name@entry=0x5555558ec922 "mem-merge", defval=defval@entry=true) at qemu/util/qemu-option.c:398 > #6 0x0000555555720a24 in host_memory_backend_init (obj=0x5555562ac970) at qemu/backends/hostmem.c:226 > > Instead of using qemu_opt_get_bool(), that didn't work with > qemu_machine_opts for a long time, we can use the machine QOM properties > directly. This was the intent. > > Signed-off-by: Eduardo Habkost <ehabkost@redhat.com> > --- > backends/hostmem.c | 9 +++++---- > 1 file changed, 5 insertions(+), 4 deletions(-) > > diff --git a/backends/hostmem.c b/backends/hostmem.c > index 61c1ac0..38a32ed 100644 > --- a/backends/hostmem.c > +++ b/backends/hostmem.c > @@ -10,6 +10,7 @@ > * See the COPYING file in the top-level directory. > */ > #include "sysemu/hostmem.h" > +#include "hw/boards.h" > #include "qapi/visitor.h" > #include "qapi-types.h" > #include "qapi-visit.h" > @@ -223,10 +224,10 @@ static void host_memory_backend_init(Object *obj) > { > HostMemoryBackend *backend = MEMORY_BACKEND(obj); > > - backend->merge = qemu_opt_get_bool(qemu_get_machine_opts(), > - "mem-merge", true); > - backend->dump = qemu_opt_get_bool(qemu_get_machine_opts(), > - "dump-guest-core", true); > + backend->merge = object_property_get_bool(OBJECT(current_machine), > + "mem-merge", &error_abort); > + backend->dump = object_property_get_bool(OBJECT(current_machine), > + "dump-guest-core", &error_abort); > backend->prealloc = mem_prealloc; > > object_property_add_bool(obj, "merge", > Thank you for fixing this, Reviewed-by: Marcel Apfelbaum <marcel@redhat.com> ^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2015-07-20 20:06 UTC | newest] Thread overview: 7+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2015-07-16 20:39 [Qemu-devel] [PATCH] hostmem: Fix qemu_opt_get_bool() crash in host_memory_backend_init() Eduardo Habkost 2015-07-16 21:02 ` Igor Mammedov 2015-07-17 20:33 ` Eduardo Habkost 2015-07-20 7:06 ` Igor Mammedov 2015-07-20 20:03 ` Eduardo Habkost 2015-07-20 20:06 ` Marcel Apfelbaum 2015-07-17 7:21 ` Marcel Apfelbaum
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