* Re: [PATCH] drm/amdkfd: Remove vla
2018-04-10 6:38 ` Christian König
@ 2018-04-10 18:42 ` Felix Kuehling
2018-04-10 18:43 ` Laura Abbott
1 sibling, 0 replies; 4+ messages in thread
From: Felix Kuehling @ 2018-04-10 18:42 UTC (permalink / raw)
To: Christian König, Laura Abbott, Oded Gabbay, Alex Deucher,
David (ChunMing) Zhou
Cc: Kees Cook, kernel-hardening, David Airlie, linux-kernel, amd-gfx,
dri-devel
Thanks Christian for catching that. I'm working on a patch series to
upstream Vega10 support, about 95% done. It will add this ASIC info for
Vega10:
static const struct kfd_device_info vega10_device_info = {
.asic_family = CHIP_VEGA10,
.max_pasid_bits = 16,
.max_no_of_hqd = 24,
.doorbell_size = 8,
.ih_ring_entry_size = 8 * sizeof(uint32_t), /* !!! IH ring entry size is bigger on Vega10 !!! */
.event_interrupt_class = &event_interrupt_class_v9,
.num_of_watch_points = 4,
.mqd_size_aligned = MQD_SIZE_ALIGNED,
.supports_cwsr = true,
.needs_iommu_device = false,
.needs_pci_atomics = false,
};
If you change it to uint32_t ih_ring_entry[8] and update the check, it
should be reasonably future proof.
Regards,
Felix
On 2018-04-10 02:38 AM, Christian König wrote:
> Am 09.04.2018 um 23:06 schrieb Laura Abbott:
>> There's an ongoing effort to remove VLAs[1] from the kernel to
>> eventually
>> turn on -Wvla. The single VLA usage in the amdkfd driver is actually
>> constant across all current platforms.
>
> Actually that isn't correct.
>
> Could be that we haven't upstreamed KFD support for them, but Vega10
> have a different interrupt ring entry size and so would cause the
> error message here.
>
>> Switch to a constant size array
>> instead.
>
> I would say to just make make the array bigger.
>
> Regards,
> Christian.
>
>>
>> [1] https://lkml.org/lkml/2018/3/7/621
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>
>> ---
>> drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 8 +++++---
>> 1 file changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> index 035c351f47c5..c9863858f343 100644
>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> @@ -139,10 +139,12 @@ static void interrupt_wq(struct work_struct *work)
>> {
>> struct kfd_dev *dev = container_of(work, struct kfd_dev,
>> interrupt_work);
>> + uint32_t ih_ring_entry[4];
>> - uint32_t ih_ring_entry[DIV_ROUND_UP(
>> - dev->device_info->ih_ring_entry_size,
>> - sizeof(uint32_t))];
>> + if (dev->device_info->ih_ring_entry_size > (4 *
>> sizeof(uint32_t))) {
>> + dev_err(kfd_chardev(), "Ring entry too small\n");
>> + return;
>> + }
>> while (dequeue_ih_ring_entry(dev, ih_ring_entry))
>> dev->device_info->event_interrupt_class->interrupt_wq(dev,
>
> _______________________________________________
> amd-gfx mailing list
> amd-gfx@lists.freedesktop.org
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^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH] drm/amdkfd: Remove vla
2018-04-10 6:38 ` Christian König
2018-04-10 18:42 ` Felix Kuehling
@ 2018-04-10 18:43 ` Laura Abbott
1 sibling, 0 replies; 4+ messages in thread
From: Laura Abbott @ 2018-04-10 18:43 UTC (permalink / raw)
To: Christian König, Oded Gabbay, Alex Deucher, David (ChunMing) Zhou
Cc: David Airlie, dri-devel, amd-gfx, linux-kernel, kernel-hardening,
Kees Cook
On 04/09/2018 11:38 PM, Christian König wrote:
> Am 09.04.2018 um 23:06 schrieb Laura Abbott:
>> There's an ongoing effort to remove VLAs[1] from the kernel to eventually
>> turn on -Wvla. The single VLA usage in the amdkfd driver is actually
>> constant across all current platforms.
>
> Actually that isn't correct.
>
> Could be that we haven't upstreamed KFD support for them, but Vega10 have a different interrupt ring entry size and so would cause the error message here.
>
>> Switch to a constant size array
>> instead.
>
> I would say to just make make the array bigger.
>
> Regards,
> Christian.
>
What array size would accommodate future chips?
>>
>> [1] https://lkml.org/lkml/2018/3/7/621
>>
>> Signed-off-by: Laura Abbott <labbott@redhat.com>
>> ---
>> drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c | 8 +++++---
>> 1 file changed, 5 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> index 035c351f47c5..c9863858f343 100644
>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_interrupt.c
>> @@ -139,10 +139,12 @@ static void interrupt_wq(struct work_struct *work)
>> {
>> struct kfd_dev *dev = container_of(work, struct kfd_dev,
>> interrupt_work);
>> + uint32_t ih_ring_entry[4];
>> - uint32_t ih_ring_entry[DIV_ROUND_UP(
>> - dev->device_info->ih_ring_entry_size,
>> - sizeof(uint32_t))];
>> + if (dev->device_info->ih_ring_entry_size > (4 * sizeof(uint32_t))) {
>> + dev_err(kfd_chardev(), "Ring entry too small\n");
>> + return;
>> + }
>> while (dequeue_ih_ring_entry(dev, ih_ring_entry))
>> dev->device_info->event_interrupt_class->interrupt_wq(dev,
>
^ permalink raw reply [flat|nested] 4+ messages in thread