On Wed, Jul 16, 2014 at 2:01 AM, Paolo Bonzini <pbonz...@redhat.com> wrote:
> Il 15/07/2014 23:25, Andrey Korolyov ha scritto:
>
>> On Wed, Jul 16, 2014 at 1:09 AM, Marcelo Tosatti <mtosa...@redhat.com>
>> wrote:
>>>
>>> On Tue, Jul 15, 2014 at 06:01:08PM +0400, Andrey Korolyov wrote:
>>>>
>>>> On Tue, Jul 15, 2014 at 10:52 AM, Andrey Korolyov <and...@xdel.ru>
>>>> wrote:
>>>>>
>>>>> On Tue, Jul 15, 2014 at 9:03 AM, Amit Shah <amit.s...@redhat.com>
>>>>> wrote:
>>>>>>
>>>>>> On (Sun) 13 Jul 2014 [16:28:56], Andrey Korolyov wrote:
>>>>>>>
>>>>>>> Hello,
>>>>>>>
>>>>>>> the issue is not specific to the iothread code because generic
>>>>>>> virtio-blk also hangs up:
>>>>>>
>>>>>>
>>>>>> Do you know which version works well? If you could bisect, that'll
>>>>>> help a lot.
>>>>>>
>>>>>> Thanks,
>>>>>> Amit
>>>>>
>>>>>
>>>>> Hi,
>>>>>
>>>>> 2.0 works definitely well. I`ll try to finish bisection today, though
>>>>> every step takes about 10 minutes to complete.
>>>>
>>>>
>>>> Yay! It is even outside of virtio-blk.
>>>>
>>>> commit 9b1786829aefb83f37a8f3135e3ea91c56001b56
>>>> Author: Marcelo Tosatti <mtosa...@redhat.com>
>>>> Date: Tue Jun 3 13:34:48 2014 -0300
>>>>
>>>> kvmclock: Ensure proper env->tsc value for kvmclock_current_nsec
>>>> calculation
>>>>
>>>> Ensure proper env->tsc value for kvmclock_current_nsec calculation.
>>>>
>>>> Reported-by: Marcin Gibuła <m.gib...@beyond.pl>
>>>> Cc: qemu-sta...@nongnu.org
>>>> Signed-off-by: Marcelo Tosatti <mtosa...@redhat.com>
>>>> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
>>>
>>>
>>> Andrey,
>>>
>>> Can you please provide instructions on how to create reproducible
>>> environment?
>>>
>>> The following patch is equivalent to the original patch, for
>>> the purposes of fixing the kvmclock problem.
>>>
>>> Perhaps it becomes easier to spot the reason for the hang you are
>>> experiencing.
>>>
>>>
>>> diff --git a/hw/i386/kvm/clock.c b/hw/i386/kvm/clock.c
>>> index 272a88a..feb5fc5 100644
>>> --- a/hw/i386/kvm/clock.c
>>> +++ b/hw/i386/kvm/clock.c
>>> @@ -17,7 +17,6 @@
>>> #include "qemu/host-utils.h"
>>> #include "sysemu/sysemu.h"
>>> #include "sysemu/kvm.h"
>>> -#include "sysemu/cpus.h"
>>> #include "hw/sysbus.h"
>>> #include "hw/kvm/clock.h"
>>>
>>> @@ -66,7 +65,6 @@ static uint64_t kvmclock_current_nsec(KVMClockState *s)
>>>
>>> cpu_physical_memory_read(kvmclock_struct_pa, &time, sizeof(time));
>>>
>>> - assert(time.tsc_timestamp <= migration_tsc);
>>> delta = migration_tsc - time.tsc_timestamp;
>>> if (time.tsc_shift < 0) {
>>> delta >>= -time.tsc_shift;
>>> @@ -125,8 +123,6 @@ static void kvmclock_vm_state_change(void *opaque,
>>> int running,
>>> if (s->clock_valid) {
>>> return;
>>> }
>>> -
>>> - cpu_synchronize_all_states();
>>> ret = kvm_vm_ioctl(kvm_state, KVM_GET_CLOCK, &data);
>>> if (ret < 0) {
>>> fprintf(stderr, "KVM_GET_CLOCK failed: %s\n",
>>> strerror(ret));
>>> diff --git a/migration.c b/migration.c
>>> index 8d675b3..34f2325 100644
>>> --- a/migration.c
>>> +++ b/migration.c
>>> @@ -608,6 +608,7 @@ static void *migration_thread(void *opaque)
>>> qemu_system_wakeup_request(QEMU_WAKEUP_REASON_OTHER);
>>> old_vm_running = runstate_is_running();
>>>
>>> + cpu_synchronize_all_states();
>>> ret = vm_stop_force_state(RUN_STATE_FINISH_MIGRATE);
>>> if (ret >= 0) {
>>> qemu_file_set_rate_limit(s->file, INT64_MAX);
>
>
> It could also be useful to apply the above patch _and_ revert
> a096b3a6732f846ec57dc28b47ee9435aa0609bf, then try to reproduce.
>
> Paolo
Yes, it solved the issue for me! (it took much time to check because
most of country` debian mirrors went inconsistent by some reason)
Also trivial addition:
diff --git a/migration.c b/migration.c
index 34f2325..65d1c88 100644
--- a/migration.c
+++ b/migration.c
@@ -25,6 +25,7 @@
#include "qemu/thread.h"
#include "qmp-commands.h"
#include "trace.h"
+#include "sysemu/cpus.h"
