Thomas Huth <th...@redhat.com> writes:
> On 02.09.2016 08:32, Nikunj A Dadhania wrote:
>> Signed-off-by: Nikunj A Dadhania <nik...@linux.vnet.ibm.com>
>> ---
>> hw/ppc/spapr_hcall.c | 11 +++++++++--
>> 1 file changed, 9 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
>> index e5eca67..daea7a0 100644
>> --- a/hw/ppc/spapr_hcall.c
>> +++ b/hw/ppc/spapr_hcall.c
>> @@ -1075,20 +1075,27 @@ target_ulong spapr_hypercall(PowerPCCPU *cpu,
>> target_ulong opcode,
>> target_ulong *args)
>> {
>> sPAPRMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
>> + target_ulong ret;
>>
>> if ((opcode <= MAX_HCALL_OPCODE)
>> && ((opcode & 0x3) == 0)) {
>> spapr_hcall_fn fn = papr_hypercall_table[opcode / 4];
>>
>> if (fn) {
>> - return fn(cpu, spapr, opcode, args);
>> + qemu_mutex_lock_iothread();
>> + ret = fn(cpu, spapr, opcode, args);
>> + qemu_mutex_unlock_iothread();
>> + return ret;
>> }
>> } else if ((opcode >= KVMPPC_HCALL_BASE) &&
>> (opcode <= KVMPPC_HCALL_MAX)) {
>> spapr_hcall_fn fn = kvmppc_hypercall_table[opcode -
>> KVMPPC_HCALL_BASE];
>>
>> if (fn) {
>> - return fn(cpu, spapr, opcode, args);
>> + qemu_mutex_lock_iothread();
>> + ret = fn(cpu, spapr, opcode, args);
>> + qemu_mutex_unlock_iothread();
>> + return ret;
>> }
>> }
>
> I think this will cause a deadlock when running on KVM since the lock is
> already taken in kvm_arch_handle_exit() - which calls spapr_hypercall()!
Ouch, havent tried this branch yet on KVM :(
Will change to emulation only as suggested in my previous mails.
Regards,
Nikunj
