On Tuesday 23 April 2019 12:15 PM, David Gibson wrote:
> On Mon, Apr 22, 2019 at 12:32:58PM +0530, Aravinda Prasad wrote:
>> This patch adds support in QEMU to handle "ibm,nmi-register"
>> and "ibm,nmi-interlock" RTAS calls.
>>
>> The machine check notification address is saved when the
>> OS issues "ibm,nmi-register" RTAS call.
>>
>> This patch also handles the case when multiple processors
>> experience machine check at or about the same time by
>> handling "ibm,nmi-interlock" call. In such cases, as per
>> PAPR, subsequent processors serialize waiting for the first
>> processor to issue the "ibm,nmi-interlock" call. The second
>> processor that also received a machine check error waits
>> till the first processor is done reading the error log.
>> The first processor issues "ibm,nmi-interlock" call
>> when the error log is consumed. This patch implements the
>> releasing part of the error-log while subsequent patch
>> (which builds error log) handles the locking part.
>>
>> Signed-off-by: Aravinda Prasad <aravi...@linux.vnet.ibm.com>
>
> Reviewed-by: David Gibson <da...@gibson.dropbear.id.au>
>
> Although I wonder if it needs to be moved later in the series to avoid
> advertising the availability of the RTAS calls to the guest before all
> the prereq patches are in place to make them work properly.
Patch 3 and 4 uses "guest_machine_check_addr", which is set in this
patch. If we push this beyond patch 4, then I feel the use of
"guest_machine_check_addr" looks odd in patch 3 and 4.
Regards,
Aravinda
>
>> ---
>> hw/ppc/spapr.c | 18 ++++++++++++++
>> hw/ppc/spapr_rtas.c | 61
>> ++++++++++++++++++++++++++++++++++++++++++++++++
>> include/hw/ppc/spapr.h | 9 ++++++-
>> 3 files changed, 87 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
>> index c56939a..6642cb5 100644
>> --- a/hw/ppc/spapr.c
>> +++ b/hw/ppc/spapr.c
>> @@ -1805,6 +1805,11 @@ static void spapr_machine_reset(void)
>> first_ppc_cpu->env.gpr[5] = 0;
>>
>> spapr->cas_reboot = false;
>> +
>> + spapr->guest_machine_check_addr = -1;
>> +
>> + /* Signal all vCPUs waiting on this condition */
>> + qemu_cond_broadcast(&spapr->mc_delivery_cond);
>> }
>>
>> static void spapr_create_nvram(SpaprMachineState *spapr)
>> @@ -2095,6 +2100,16 @@ static const VMStateDescription vmstate_spapr_dtb = {
>> },
>> };
>>
>> +static const VMStateDescription vmstate_spapr_machine_check = {
>> + .name = "spapr_machine_check",
>> + .version_id = 1,
>> + .minimum_version_id = 1,
>> + .fields = (VMStateField[]) {
>> + VMSTATE_UINT64(guest_machine_check_addr, SpaprMachineState),
>> + VMSTATE_END_OF_LIST()
>> + },
>> +};
>> +
>> static const VMStateDescription vmstate_spapr = {
>> .name = "spapr",
>> .version_id = 3,
>> @@ -2127,6 +2142,7 @@ static const VMStateDescription vmstate_spapr = {
>> &vmstate_spapr_dtb,
>> &vmstate_spapr_cap_large_decr,
>> &vmstate_spapr_cap_ccf_assist,
>> + &vmstate_spapr_machine_check,
>> NULL
>> }
>> };
>> @@ -3068,6 +3084,8 @@ static void spapr_machine_init(MachineState *machine)
>>
>> kvmppc_spapr_enable_inkernel_multitce();
>> }
>> +
>> + qemu_cond_init(&spapr->mc_delivery_cond);
>> }
>>
>> static int spapr_kvm_type(MachineState *machine, const char *vm_type)
>> diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
>> index ee24212..c2f3991 100644
>> --- a/hw/ppc/spapr_rtas.c
>> +++ b/hw/ppc/spapr_rtas.c
>> @@ -348,6 +348,39 @@ static void rtas_get_power_level(PowerPCCPU *cpu,
>> SpaprMachineState *spapr,
>> rtas_st(rets, 1, 100);
>> }
>>
>> +static void rtas_ibm_nmi_register(PowerPCCPU *cpu,
>> + SpaprMachineState *spapr,
>> + uint32_t token, uint32_t nargs,
>> + target_ulong args,
>> + uint32_t nret, target_ulong rets)
>> +{
>> + uint64_t rtas_addr = spapr_get_rtas_addr();
>> +
>> + if (!rtas_addr) {
>> + rtas_st(rets, 0, RTAS_OUT_NOT_SUPPORTED);
>> + return;
>> + }
>> +
>> + spapr->guest_machine_check_addr = rtas_ld(args, 1);
>> + rtas_st(rets, 0, RTAS_OUT_SUCCESS);
>> +}
>> +
>> +static void rtas_ibm_nmi_interlock(PowerPCCPU *cpu,
>> + SpaprMachineState *spapr,
>> + uint32_t token, uint32_t nargs,
>> + target_ulong args,
>> + uint32_t nret, target_ulong rets)
>> +{
>> + if (!spapr->guest_machine_check_addr) {
>> + /* NMI register not called */
>> + rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
>> + } else {
>> + qemu_cond_signal(&spapr->mc_delivery_cond);
>> + rtas_st(rets, 0, RTAS_OUT_SUCCESS);
>> + }
>> +}
>> +
>> +
>> static struct rtas_call {
>> const char *name;
>> spapr_rtas_fn fn;
>> @@ -466,6 +499,30 @@ void spapr_load_rtas(SpaprMachineState *spapr, void
>> *fdt, hwaddr addr)
>> }
>> }
>>
>> +uint64_t spapr_get_rtas_addr(void)
>> +{
>> + SpaprMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
>> + int rtas_node;
>> + const struct fdt_property *rtas_addr_prop;
>> + void *fdt = spapr->fdt_blob;
>> + uint32_t rtas_addr;
>> +
>> + /* fetch rtas addr from fdt */
>> + rtas_node = fdt_path_offset(fdt, "/rtas");
>> + if (rtas_node == 0) {
>> + return 0;
>> + }
>> +
>> + rtas_addr_prop = fdt_get_property(fdt, rtas_node, "linux,rtas-base",
>> NULL);
>> + if (!rtas_addr_prop) {
>> + return 0;
>> + }
>> +
>> + rtas_addr = fdt32_to_cpu(*(uint32_t *)rtas_addr_prop->data);
>> + return (uint64_t)rtas_addr;
>> +}
>> +
>> +
>> static void core_rtas_register_types(void)
>> {
>> spapr_rtas_register(RTAS_DISPLAY_CHARACTER, "display-character",
>> @@ -489,6 +546,10 @@ static void core_rtas_register_types(void)
>> rtas_set_power_level);
>> spapr_rtas_register(RTAS_GET_POWER_LEVEL, "get-power-level",
>> rtas_get_power_level);
>> + spapr_rtas_register(RTAS_IBM_NMI_REGISTER, "ibm,nmi-register",
>> + rtas_ibm_nmi_register);
>> + spapr_rtas_register(RTAS_IBM_NMI_INTERLOCK, "ibm,nmi-interlock",
>> + rtas_ibm_nmi_interlock);
>> }
>>
>> type_init(core_rtas_register_types)
>> diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
>> index 7e32f30..ec6f33e 100644
>> --- a/include/hw/ppc/spapr.h
>> +++ b/include/hw/ppc/spapr.h
>> @@ -187,6 +187,10 @@ struct SpaprMachineState {
>> * occurs during the unplug process. */
>> QTAILQ_HEAD(, SpaprDimmState) pending_dimm_unplugs;
>>
>> + /* State related to "ibm,nmi-register" and "ibm,nmi-interlock" calls */
>> + target_ulong guest_machine_check_addr;
>> + QemuCond mc_delivery_cond;
>> +
>> /*< public >*/
>> char *kvm_type;
>> char *host_model;
>> @@ -623,8 +627,10 @@ target_ulong spapr_hypercall(PowerPCCPU *cpu,
>> target_ulong opcode,
>> #define RTAS_IBM_CREATE_PE_DMA_WINDOW (RTAS_TOKEN_BASE + 0x27)
>> #define RTAS_IBM_REMOVE_PE_DMA_WINDOW (RTAS_TOKEN_BASE + 0x28)
>> #define RTAS_IBM_RESET_PE_DMA_WINDOW (RTAS_TOKEN_BASE + 0x29)
>> +#define RTAS_IBM_NMI_REGISTER (RTAS_TOKEN_BASE + 0x2A)
>> +#define RTAS_IBM_NMI_INTERLOCK (RTAS_TOKEN_BASE + 0x2B)
>>
>> -#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2A)
>> +#define RTAS_TOKEN_MAX (RTAS_TOKEN_BASE + 0x2C)
>>
>> /* RTAS ibm,get-system-parameter token values */
>> #define RTAS_SYSPARM_SPLPAR_CHARACTERISTICS 20
>> @@ -874,4 +880,5 @@ void spapr_check_pagesize(SpaprMachineState *spapr,
>> hwaddr pagesize,
>> #define SPAPR_OV5_XIVE_BOTH 0x80 /* Only to advertise on the platform */
>>
>> void spapr_set_all_lpcrs(target_ulong value, target_ulong mask);
>> +uint64_t spapr_get_rtas_addr(void);
>> #endif /* HW_SPAPR_H */
>>
>
--
Regards,
Aravinda
