[AMD Official Use Only]


> -----Original Message-----
> From: Kuehling, Felix <felix.kuehl...@amd.com>
> Sent: Tuesday, March 15, 2022 2:41 AM
> To: Zhou1, Tao <tao.zh...@amd.com>; amd-gfx@lists.freedesktop.org; Zhang,
> Hawking <hawking.zh...@amd.com>; Yang, Stanley
> <stanley.y...@amd.com>; Chai, Thomas <yipeng.c...@amd.com>
> Subject: Re: [PATCH 3/3] drm/amdkfd: add RAS poison consumption support for
> utcl2
> 
> I'm not sure I understand this change. It looks like you will check the RAS 
> poison
> status on every UTCL2 VM fault? Is that because there is no dedicated 
> interrupt
> source or client ID to distinguish UTCL2 poison consumption from VM faults?
> 
> Why is kfd_signal_poison_consumed_event not done for UTCL2 poison
> consumption? The comment says, because it's signaled to user mode as a VM
> fault. But a VM fault and a poison consumption event are different.
> You're basically sending the wrong event to user mode. Maybe it doesn't make a
> big difference in practice at the moment. But that could change in the future.

[Tao] yes, no dedicated interrupt source, so I need to check FED bit in 
VM_L2_PROTECTION_FAULT_STATUS to distinguish it from general VM fault.

I inject error to PDE1 to trigger UTCL2 poison consumption, both 
kfd_signal_poison_consumed_event and kfd_signal_vm_fault_event can be handled 
by ROCr in my experiment (bus error vs. coredump and APP can be killed).
I think we can take UTCL2 consumption as a special VM fault, so I select 
kfd_signal_vm_fault_event. Anyway, this can be discussed furtherly.

> 
> Two more comments inline ...
> 
> 
> Am 2022-03-14 um 03:03 schrieb Tao Zhou:
> > Do RAS page retirement and use gpu reset as fallback in utcl2 fault
> > handler.
> >
> > Signed-off-by: Tao Zhou <tao.zh...@amd.com>
> > ---
> >   .../gpu/drm/amd/amdkfd/kfd_int_process_v9.c   | 23 ++++++++++++++++---
> >   1 file changed, 20 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_int_process_v9.c
> > b/drivers/gpu/drm/amd/amdkfd/kfd_int_process_v9.c
> > index f7def0bf0730..3991f71d865b 100644
> > --- a/drivers/gpu/drm/amd/amdkfd/kfd_int_process_v9.c
> > +++ b/drivers/gpu/drm/amd/amdkfd/kfd_int_process_v9.c
> > @@ -93,11 +93,12 @@ enum SQ_INTERRUPT_ERROR_TYPE {
> >   static void event_interrupt_poison_consumption(struct kfd_dev *dev,
> >                             const uint32_t *ih_ring_entry)
> >   {
> > -   uint16_t source_id, pasid;
> > +   uint16_t source_id, client_id, pasid;
> >     int ret = -EINVAL;
> >     struct kfd_process *p;
> >
> >     source_id = SOC15_SOURCE_ID_FROM_IH_ENTRY(ih_ring_entry);
> > +   client_id = SOC15_CLIENT_ID_FROM_IH_ENTRY(ih_ring_entry);
> >     pasid = SOC15_PASID_FROM_IH_ENTRY(ih_ring_entry);
> >
> >     p = kfd_lookup_process_by_pasid(pasid);
> > @@ -110,6 +111,7 @@ static void
> event_interrupt_poison_consumption(struct kfd_dev *dev,
> >             return;
> >     }
> >
> > +   pr_debug("RAS poison consumption handling\n");
> >     atomic_set(&p->poison, 1);
> >     kfd_unref_process(p);
> >
> > @@ -119,10 +121,14 @@ static void
> event_interrupt_poison_consumption(struct kfd_dev *dev,
> >             break;
> >     case SOC15_INTSRC_SDMA_ECC:
> >     default:
> > +           if (client_id == SOC15_IH_CLIENTID_UTCL2)
> > +                   ret = kfd_dqm_evict_pasid(dev->dqm, pasid);
> >             break;
> >     }
> >
> > -   kfd_signal_poison_consumed_event(dev, pasid);
> > +   /* utcl2 page fault has its own vm fault event */
> > +   if (client_id != SOC15_IH_CLIENTID_UTCL2)
> > +           kfd_signal_poison_consumed_event(dev, pasid);
> >
> >     /* resetting queue passes, do page retirement without gpu reset
> >      * resetting queue fails, fallback to gpu reset solution @@ -314,7
> > +320,18 @@ static void event_interrupt_wq_v9(struct kfd_dev *dev,
> >             info.prot_write = ring_id & 0x20;
> >
> >             kfd_smi_event_update_vmfault(dev, pasid);
> > -           kfd_dqm_evict_pasid(dev->dqm, pasid);
> > +
> > +           if (client_id == SOC15_IH_CLIENTID_UTCL2 &&
> > +               dev->kfd2kgd->is_ras_utcl2_poison &&
> > +               dev->kfd2kgd->is_ras_utcl2_poison(dev->adev, client_id)) {
> > +                   event_interrupt_poison_consumption(dev,
> ih_ring_entry);
> > +
> > +                   if (dev->kfd2kgd->utcl2_fault_clear)
> > +                           dev->kfd2kgd->utcl2_fault_clear(dev->adev);
> > +           }
> > +           else
> 
> Else should be on the same line as }. Please run checkpatch.pl, it would 
> catch this.
> It's also good practice to use {}-braces around the else-branch if you have
> braces around the if-branch.

[Tao] accepted

> 
> 
> > +                   kfd_dqm_evict_pasid(dev->dqm, pasid);
> > +
> >             kfd_signal_vm_fault_event(dev, pasid, &info);
> 
> If you move kfd_signal_vm_fault_event into the else-branch, you can
> unconditionally send the correct poison consumption event to user mode in
> event_interrupt_poison_consumption.
> 
> Regards,
>    Felix
> 
> 
> >     }
> >   }

Reply via email to