On Tue, Nov 05, 2024 at 11:32:37AM -0600, Lucas De Marchi wrote:
> On Fri, Nov 01, 2024 at 12:16:19PM -0700, Matthew Brost wrote:
> > On Fri, Nov 01, 2024 at 12:38:19PM -0500, Lucas De Marchi wrote:
> > > On Fri, Nov 01, 2024 at 05:01:57PM +0000, Matthew Auld wrote:
> > > > The GGTT looks to be stored inside stolen memory on igpu which is not
> > > > treated as normal RAM. The core kernel skips this memory range when
> > > > creating the hibernation image, therefore when coming back from
> > >
> > > can you add the log for e820 mapping to confirm?
> > >
> > > > hibernation the GGTT programming is lost. This seems to cause issues
> > > > with broken resume where GuC FW fails to load:
> > > >
> > > > [drm] *ERROR* GT0: load failed: status = 0x400000A0, time = 10ms, freq = 1250MHz (req 1300MHz), done = -1
> > > > [drm] *ERROR* GT0: load failed: status: Reset = 0, BootROM = 0x50, UKernel = 0x00, MIA = 0x00, Auth = 0x01
> > > > [drm] *ERROR* GT0: firmware signature verification failed
> > > > [drm] *ERROR* CRITICAL: Xe has declared device 0000:00:02.0 as wedged.
> > >
> > > it seems the message above is cut short. Just above these lines don't
> > > you have a log with __xe_guc_upload? Which means: we actually upload the
> > > firmware again to stolen and it doesn't matter that we lost it when
> > > hibernating.
> > >
> >
> > The image is always uploaded. The upload logic uses a GGTT address to
> > find firmware image in SRAM...
> >
> > See snippet from uc_fw_xfer:
> >
> > 821 /* Set the source address for the uCode */
> > 822 src_offset = uc_fw_ggtt_offset(uc_fw) + uc_fw->css_offset;
> > 823 xe_mmio_write32(mmio, DMA_ADDR_0_LOW, lower_32_bits(src_offset));
> > 824 xe_mmio_write32(mmio, DMA_ADDR_0_HIGH,
> > 825 upper_32_bits(src_offset) | DMA_ADDRESS_SPACE_GGTT);
> >
> > If the GGTT mappings are in stolen and not restored we will not be
> > uploading the correct data for the image.
> >
> > See the gitlab issue, this has been confirmed to fix a real problem from
> > a customer.
>
> I don't doubt it fixes it, but the justification here is not making much
> sense. AFAICS it doesn't really correspond to what the patch is doing.
>
> >
> > Matt
> >
> > > It'd be good to know the size of the rsa key in the failing scenarios.
> > >
> > > Also it seems this is also reproduced in DG2 and I wonder if it's the
> > > same issue or something different:
> > >
> > > [drm:__xe_guc_upload.isra.0 [xe]] GT0: load still in progress, timeouts = 0, freq = 1700MHz (req 2050MHz), status = 0x00000064 [0x32/00]
> > > [drm:__xe_guc_upload.isra.0 [xe]] GT0: load still in progress, timeouts = 0, freq = 1700MHz (req 2050MHz), status = 0x00000072 [0x39/00]
> > > [drm:__xe_guc_upload.isra.0 [xe]] GT0: load still in progress, timeouts = 0, freq = 1700MHz (req 2050MHz), status = 0x00000086 [0x43/00]
> > > [drm] *ERROR* GT0: load failed: status = 0x400000A0, time = 5ms, freq = 1700MHz (req 2050MHz), done = -1
> > > [drm] *ERROR* GT0: load failed: status: Reset = 0, BootROM = 0x50, UKernel = 0x00, MIA = 0x00, Auth = 0x01
> > > [drm] *ERROR* GT0: firmware signature verification failed
> > >
> > > Cc Ulisses.
> > >
> > > >
> > > > Current GGTT users are kernel internal and tracked as pinned, so it
> > > > should be possible to hook into the existing save/restore logic that we
> > > > use for dgpu, where the actual evict is skipped but on restore we
> > > > importantly restore the GGTT programming. This has been confirmed to
> > > > fix hibernation on at least ADL and MTL, though likely all igpu
> > > > platforms are affected.
> > > >
> > > > This also means we have a hole in our testing, where the existing s4
> > > > tests only really test the driver hooks, and don't go as far as actually
> > > > rebooting and restoring from the hibernation image and in turn powering
> > > > down RAM (and therefore losing the contents of stolen).
> > >
> > > yeah, the problem is that enabling it to go through the entire sequence
> > > we reproduce all kind of issues in other parts of the kernel and userspace
> > > env leading to flaky tests that are usually red in CI. The most annoying
> > > one is the network not coming back so we mark the test as failure
> > > (actually abort. since we stop running everything).
> > >
> > >
> > > >
> > > > v2 (Brost)
> > > > - Remove extra newline and drop unnecessary parentheses.
> > > >
> > > > Fixes: dd08ebf6c352 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
> > > > Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/3275
> > > > Signed-off-by: Matthew Auld <matthew.auld@xxxxxxxxx>
> > > > Cc: Matthew Brost <matthew.brost@xxxxxxxxx>
> > > > Cc: <stable@xxxxxxxxxxxxxxx> # v6.8+
> > > > Reviewed-by: Matthew Brost <matthew.brost@xxxxxxxxx>
> > > > ---
> > > > drivers/gpu/drm/xe/xe_bo.c | 37 ++++++++++++++------------------
> > > > drivers/gpu/drm/xe/xe_bo_evict.c | 6 ------
> > > > 2 files changed, 16 insertions(+), 27 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c
> > > > index 8286cbc23721..549866da5cd1 100644
> > > > --- a/drivers/gpu/drm/xe/xe_bo.c
> > > > +++ b/drivers/gpu/drm/xe/xe_bo.c
> > > > @@ -952,7 +952,10 @@ int xe_bo_restore_pinned(struct xe_bo *bo)
> > > > if (WARN_ON(!xe_bo_is_pinned(bo)))
> > > > return -EINVAL;
> > > >
> > > > - if (WARN_ON(xe_bo_is_vram(bo) || !bo->ttm.ttm))
> > > > + if (WARN_ON(xe_bo_is_vram(bo)))
> > > > + return -EINVAL;
> > > > +
> > > > + if (WARN_ON(!bo->ttm.ttm && !xe_bo_is_stolen(bo)))
> > > > return -EINVAL;
> > > >
> > > > if (!mem_type_is_vram(place->mem_type))
> > > > @@ -1774,6 +1777,7 @@ int xe_bo_pin_external(struct xe_bo *bo)
> > > >
> > > > int xe_bo_pin(struct xe_bo *bo)
> > > > {
> > > > + struct ttm_place *place = &bo->placements[0];
> > > > struct xe_device *xe = xe_bo_device(bo);
> > > > int err;
> > > >
> > > > @@ -1804,8 +1808,6 @@ int xe_bo_pin(struct xe_bo *bo)
> > > > */
> > > > if (IS_DGFX(xe) && !(IS_ENABLED(CONFIG_DRM_XE_DEBUG) &&
> > > > bo->flags & XE_BO_FLAG_INTERNAL_TEST)) {
> > > > - struct ttm_place *place = &(bo->placements[0]);
> > > > -
> > > > if (mem_type_is_vram(place->mem_type)) {
> > > > xe_assert(xe, place->flags & TTM_PL_FLAG_CONTIGUOUS);
> > > >
> > > > @@ -1813,13 +1815,12 @@ int xe_bo_pin(struct xe_bo *bo)
> > > > vram_region_gpu_offset(bo->ttm.resource)) >> PAGE_SHIFT;
> > > > place->lpfn = place->fpfn + (bo->size >> PAGE_SHIFT);
> > > > }
> > > > + }
> > > >
> > > > - if (mem_type_is_vram(place->mem_type) ||
> > > > - bo->flags & XE_BO_FLAG_GGTT) {
> > > > - spin_lock(&xe->pinned.lock);
> > > > - list_add_tail(&bo->pinned_link, &xe->pinned.kernel_bo_present);
> > > > - spin_unlock(&xe->pinned.lock);
> > > > - }
> > > > + if (mem_type_is_vram(place->mem_type) || bo->flags & XE_BO_FLAG_GGTT) {
>
>
> again... why do you say we are restoring the GGTT itself? this seems
> rather to allow pinning and then restoring anything that has
> the XE_BO_FLAG_GGTT - that's any BO that uses the GGTT, not the GGTT.
>
I think what you are sayings is right - the patch restores every BOs
GGTT mappings rather than restoring the entire contents of the GGTT.
This might be a larger problem then as I think the scratch GGTT entries
will not be restored - this is problem for both igpu and dgfx devices.
This patch should help but is not complete.
I think we need a follow up to either...
1. Setup all scratch pages in the GGTT prior to calling
xe_bo_restore_kernel and use this flow to restore individual BOs GGTTs.
2. Drop restoring of individual BOs GGTTs entirely and save / restore
the GGTTs contents.
Does this make sense?
> From drivers/gpu/drm/xe/xe_uc_fw.c:
>
> xe_uc_fw_init() {
> uc_fw_copy(uc_fw, fw->data, fw->size,
> XE_BO_FLAG_SYSTEM | XE_BO_FLAG_GGTT |
> XE_BO_FLAG_GGTT_INVALIDATE) {
>
> obj = xe_managed_bo_create_from_data(xe, tile, data, size, flags);
> uc_fw->bo = obj;
> }
> }
>
> So what you are doing here is to
> a) copy each of those BOs to temporary system memory;
> b) restore them on resume;
> c) map it again on the ggtt.
>
> Is this correct and intended? Looking at XE_BO_FLAG_GGTT there will be
> several things we are going to store to disk and afaics it will be duplicated
> on igpu. From the commit message I was not expecting this.
>
This is how I thought the patch was intended when I RB'd this but see
above - we still have issues here.
Matt
> Lucas De Marchi
>
> > >
> > > should this test for devmem so we restore everything rather than just
> > > ggtt?
> > >
> > > Lucas De Marchi
> > >
> > > > + spin_lock(&xe->pinned.lock);
> > > > + list_add_tail(&bo->pinned_link, &xe->pinned.kernel_bo_present);
> > > > + spin_unlock(&xe->pinned.lock);
> > > > }
> > > >
> > > > ttm_bo_pin(&bo->ttm);
> > > > @@ -1867,24 +1868,18 @@ void xe_bo_unpin_external(struct xe_bo *bo)
> > > >
> > > > void xe_bo_unpin(struct xe_bo *bo)
> > > > {
> > > > + struct ttm_place *place = &bo->placements[0];
> > > > struct xe_device *xe = xe_bo_device(bo);
> > > >
> > > > xe_assert(xe, !bo->ttm.base.import_attach);
> > > > xe_assert(xe, xe_bo_is_pinned(bo));
> > > >
> > > > - if (IS_DGFX(xe) && !(IS_ENABLED(CONFIG_DRM_XE_DEBUG) &&
> > > > - bo->flags & XE_BO_FLAG_INTERNAL_TEST)) {
> > > > - struct ttm_place *place = &(bo->placements[0]);
> > > > -
> > > > - if (mem_type_is_vram(place->mem_type) ||
> > > > - bo->flags & XE_BO_FLAG_GGTT) {
> > > > - spin_lock(&xe->pinned.lock);
> > > > - xe_assert(xe, !list_empty(&bo->pinned_link));
> > > > - list_del_init(&bo->pinned_link);
> > > > - spin_unlock(&xe->pinned.lock);
> > > > - }
> > > > + if (mem_type_is_vram(place->mem_type) || bo->flags & XE_BO_FLAG_GGTT) {
> > > > + spin_lock(&xe->pinned.lock);
> > > > + xe_assert(xe, !list_empty(&bo->pinned_link));
> > > > + list_del_init(&bo->pinned_link);
> > > > + spin_unlock(&xe->pinned.lock);
> > > > }
> > > > -
> > > > ttm_bo_unpin(&bo->ttm);
> > > > }
> > > >
> > > > diff --git a/drivers/gpu/drm/xe/xe_bo_evict.c b/drivers/gpu/drm/xe/xe_bo_evict.c
> > > > index 32043e1e5a86..b01bc20eb90b 100644
> > > > --- a/drivers/gpu/drm/xe/xe_bo_evict.c
> > > > +++ b/drivers/gpu/drm/xe/xe_bo_evict.c
> > > > @@ -34,9 +34,6 @@ int xe_bo_evict_all(struct xe_device *xe)
> > > > u8 id;
> > > > int ret;
> > > >
> > > > - if (!IS_DGFX(xe))
> > > > - return 0;
> > > > -
> > > > /* User memory */
> > > > for (mem_type = XE_PL_VRAM0; mem_type <= XE_PL_VRAM1; ++mem_type) {
> > > > struct ttm_resource_manager *man =
> > > > @@ -125,9 +122,6 @@ int xe_bo_restore_kernel(struct xe_device *xe)
> > > > struct xe_bo *bo;
> > > > int ret;
> > > >
> > > > - if (!IS_DGFX(xe))
> > > > - return 0;
> > > > -
> > > > spin_lock(&xe->pinned.lock);
> > > > for (;;) {
> > > > bo = list_first_entry_or_null(&xe->pinned.evicted,
> > > > --
> > > > 2.47.0
> > > >
