Re: [Qemu-devel] [PATCH v5] ppc: spapr-rtas - implement os-term rtas call

[Nikunj A Dadhania]

Alexander Graf <address@hidden> writes:

> On 30.06.2014, at 17:49, Tyrel Datwyler <address@hidden> wrote:
>
>> On 06/30/2014 01:35 AM, Nikunj A Dadhania wrote:
>>> PAPR compliant guest calls this in absence of kdump. This finally
>>> reaches the guest and can be handled according to the policies set by
>>> higher level tools(like taking dump) for further analysis by tools like
>>> crash.
>>> 
>>> Linux kernel calls ibm,os-term when extended property of os-term is set.
>>> This makes sure that a return to the linux kernel is gauranteed.
>>> 
>>> CC: Benjamin Herrenschmidt <address@hidden>
>>> CC: Anton Blanchard <address@hidden>
>>> CC: Alexander Graf <address@hidden>
>>> CC: Tyrel Datwyler <address@hidden>
>>> Signed-off-by: Nikunj A Dadhania <address@hidden>
>>> 
>>> ---
>>> 
>>> v2: rebase to ppcnext
>>> v3: Do not stop the VM, and update comments
>>> v4: update spapr_register_rtas and qapi_event changes
>>> v5: set ibm,extended-os-term as null encoded property
>>> ---
>>> hw/ppc/spapr.c         |  9 +++++++++
>>> hw/ppc/spapr_rtas.c    | 15 +++++++++++++++
>>> include/hw/ppc/spapr.h |  1 -
>>> 3 files changed, 24 insertions(+), 1 deletion(-)
>>> 
>>> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
>>> index 307c58d..e6c9014 100644
>>> --- a/hw/ppc/spapr.c
>>> +++ b/hw/ppc/spapr.c
>>> @@ -520,6 +520,15 @@ static void *spapr_create_fdt_skel(hwaddr initrd_base,
>>> 
>>>     _FDT((fdt_property_cell(fdt, "rtas-error-log-max", 
>>> RTAS_ERROR_LOG_MAX)));
>>> 
>>> +    /*
>>> +     * According to PAPR, rtas ibm,os-term, does not gaurantee a return
>>> +     * back to the guest cpu.
>>> +     *
>>> +     * While an additional ibm,extended-os-term property indicates that
>>> +     * rtas call return will always occur. Set this property.
>>> +     */
>>> +    _FDT((fdt_property(fdt, "ibm,extended-os-term", NULL, 0)));
>>> +
>>>     _FDT((fdt_end_node(fdt)));
>>> 
>>>     /* interrupt controller */
>>> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
>>> index 9ba1ba6..2ec2a8e 100644
>>> --- a/hw/ppc/spapr_rtas.c
>>> +++ b/hw/ppc/spapr_rtas.c
>>> @@ -277,6 +277,19 @@ static void rtas_ibm_set_system_parameter(PowerPCCPU 
>>> *cpu,
>>>     rtas_st(rets, 0, ret);
>>> }
>>> 
>>> +static void rtas_ibm_os_term(PowerPCCPU *cpu,
>>> +                            sPAPREnvironment *spapr,
>>> +                            uint32_t token, uint32_t nargs,
>>> +                            target_ulong args,
>>> +                            uint32_t nret, target_ulong rets)
>>> +{
>>> +    target_ulong ret = 0;
>>> +
>>> +    qapi_event_send_guest_panicked(GUEST_PANIC_ACTION_PAUSE, &error_abort);
>>> +
>>> +    rtas_st(rets, 0, ret);
>>> +}
>>> +
>>> static struct rtas_call {
>>>     const char *name;
>>>     spapr_rtas_fn fn;
>>> @@ -404,6 +417,8 @@ static void core_rtas_register_types(void)
>>>     spapr_rtas_register(RTAS_IBM_SET_SYSTEM_PARAMETER,
>>>                         "ibm,set-system-parameter",
>>>                         rtas_ibm_set_system_parameter);
>>> +    spapr_rtas_register(RTAS_IBM_OS_TERM, "ibm,os-term",
>>> +                        rtas_ibm_os_term);
>>> }
>>> 
>>> type_init(core_rtas_register_types)
>>> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
>>> index bbba51a..4e96381 100644
>>> --- a/include/hw/ppc/spapr.h
>>> +++ b/include/hw/ppc/spapr.h
>>> @@ -382,7 +382,6 @@ int spapr_allocate_irq_block(int num, bool lsi, bool 
>>> msi);
>>> #define RTAS_GET_SENSOR_STATE                   (RTAS_TOKEN_BASE + 0x1D)
>>> #define RTAS_IBM_CONFIGURE_CONNECTOR            (RTAS_TOKEN_BASE + 0x1E)
>>> #define RTAS_IBM_OS_TERM                        (RTAS_TOKEN_BASE + 0x1F)
>>> -#define RTAS_IBM_EXTENDED_OS_TERM               (RTAS_TOKEN_BASE + 0x20)
>>> 
>>> #define RTAS_TOKEN_MAX                          (RTAS_TOKEN_BASE + 0x21)
>> 
>> With the removal of RTAS_IBM_EXTENDED_OS_TERM doesn't RTAS_TOKEN_MAX
>> need to be decremented to (RTAS_TOKEN_BASE + 0x20)?

You are right.

> Good catch. Fixed in my queue.

Thanks, Any reason we dont have that as enum?

Regards
Nikunj