Message ID | 20221223092011.11657-1-nirmoy.das@intel.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | drm/i915: Reserve enough fence slot for i915_vma_unbind_async | expand |
On Fri, 23 Dec 2022 at 09:20, Nirmoy Das <nirmoy.das@intel.com> wrote: > > A nested dma_resv_reserve_fences(1) will not reserve slot from the > 2nd call onwards and folowing dma_resv_add_fence() might hit the > "BUG_ON(fobj->num_fences >= fobj->max_fences)" check. > > I915 hit above nested dma_resv case in ttm_bo_handle_move_mem() with > async unbind: > > dma_resv_reserve_fences() from --> ttm_bo_handle_move_mem() > dma_resv_reserve_fences() from --> i915_vma_unbind_async() > dma_resv_add_fence() from --> i915_vma_unbind_async() > dma_resv_add_fence() from -->ttm_bo_move_accel_cleanup() > > Resolve this by adding an extra fence in i915_vma_unbind_async(). > > Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> > Signed-off-by: Nirmoy Das <nirmoy.das@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Does this need a fixes tag? Fixes: 2f6b90da9192 ("drm/i915: Use vma resources for async unbinding") Cc: <stable@vger.kernel.org> # v5.18+ I can add when pushing. > --- > drivers/gpu/drm/i915/i915_vma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c > index 7d044888ac33..5ac4c1c2403c 100644 > --- a/drivers/gpu/drm/i915/i915_vma.c > +++ b/drivers/gpu/drm/i915/i915_vma.c > @@ -2149,7 +2149,7 @@ int i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm) > if (!obj->mm.rsgt) > return -EBUSY; > > - err = dma_resv_reserve_fences(obj->base.resv, 1); > + err = dma_resv_reserve_fences(obj->base.resv, 2); > if (err) > return -EBUSY; > > -- > 2.38.0 >
On 1/5/2023 10:56 AM, Matthew Auld wrote: > On Fri, 23 Dec 2022 at 09:20, Nirmoy Das <nirmoy.das@intel.com> wrote: >> A nested dma_resv_reserve_fences(1) will not reserve slot from the >> 2nd call onwards and folowing dma_resv_add_fence() might hit the >> "BUG_ON(fobj->num_fences >= fobj->max_fences)" check. >> >> I915 hit above nested dma_resv case in ttm_bo_handle_move_mem() with >> async unbind: >> >> dma_resv_reserve_fences() from --> ttm_bo_handle_move_mem() >> dma_resv_reserve_fences() from --> i915_vma_unbind_async() >> dma_resv_add_fence() from --> i915_vma_unbind_async() >> dma_resv_add_fence() from -->ttm_bo_move_accel_cleanup() >> >> Resolve this by adding an extra fence in i915_vma_unbind_async(). >> >> Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> >> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com> > Reviewed-by: Matthew Auld <matthew.auld@intel.com> > > Does this need a fixes tag? > > Fixes: 2f6b90da9192 ("drm/i915: Use vma resources for async unbinding") > Cc: <stable@vger.kernel.org> # v5.18+ > > I can add when pushing. Yes, please add that. Thanks, Nirmoy > >> --- >> drivers/gpu/drm/i915/i915_vma.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c >> index 7d044888ac33..5ac4c1c2403c 100644 >> --- a/drivers/gpu/drm/i915/i915_vma.c >> +++ b/drivers/gpu/drm/i915/i915_vma.c >> @@ -2149,7 +2149,7 @@ int i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm) >> if (!obj->mm.rsgt) >> return -EBUSY; >> >> - err = dma_resv_reserve_fences(obj->base.resv, 1); >> + err = dma_resv_reserve_fences(obj->base.resv, 2); >> if (err) >> return -EBUSY; >> >> -- >> 2.38.0 >>
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c index 7d044888ac33..5ac4c1c2403c 100644 --- a/drivers/gpu/drm/i915/i915_vma.c +++ b/drivers/gpu/drm/i915/i915_vma.c @@ -2149,7 +2149,7 @@ int i915_vma_unbind_async(struct i915_vma *vma, bool trylock_vm) if (!obj->mm.rsgt) return -EBUSY; - err = dma_resv_reserve_fences(obj->base.resv, 1); + err = dma_resv_reserve_fences(obj->base.resv, 2); if (err) return -EBUSY;
A nested dma_resv_reserve_fences(1) will not reserve slot from the 2nd call onwards and folowing dma_resv_add_fence() might hit the "BUG_ON(fobj->num_fences >= fobj->max_fences)" check. I915 hit above nested dma_resv case in ttm_bo_handle_move_mem() with async unbind: dma_resv_reserve_fences() from --> ttm_bo_handle_move_mem() dma_resv_reserve_fences() from --> i915_vma_unbind_async() dma_resv_add_fence() from --> i915_vma_unbind_async() dma_resv_add_fence() from -->ttm_bo_move_accel_cleanup() Resolve this by adding an extra fence in i915_vma_unbind_async(). Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Nirmoy Das <nirmoy.das@intel.com> --- drivers/gpu/drm/i915/i915_vma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)