Hi Rodrigo, On 6/26/2024 5:50 PM, Rodrigo Vivi wrote:
On Wed, Jun 26, 2024 at 05:36:43PM +0200, Nirmoy Das wrote:Hi Rodrigo,On 6/26/2024 5:24 PM, Rodrigo Vivi wrote: On Wed, Jun 26, 2024 at 04:33:18PM +0200, Nirmoy Das wrote: >We report object allocation failures to userspace with ENOMEM>so add __GFP_NOWARN to remove superfluous oom warnings.>Closes: [1]https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/4936>Cc: Andi Shyti [2]<andi.shyti@xxxxxxxxxxxxxxx> >Signed-off-by: Nirmoy Das [3]<nirmoy.das@xxxxxxxxx> >--- > drivers/gpu/drm/i915/i915_scatterlist.c | 8 ++++---- > 1 file changed, 4 insertions(+), 4 deletions(-)>diff --git a/drivers/gpu/drm/i915/i915_scatterlist.c b/drivers/gpu/drm/i915/i915_scatterlist.c>index e93d2538f298..4d830740946d 100644 >--- a/drivers/gpu/drm/i915/i915_scatterlist.c >+++ b/drivers/gpu/drm/i915/i915_scatterlist.c >@@ -90,7 +90,7 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, > > GEM_BUG_ON(!max_segment); > >- rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL); >+ rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL | __GFP_NOWARN); > if (!rsgt) > return ERR_PTR(-ENOMEM);is it really safe?I don't believe we can guarantee a good fallback plan here if allocation fails. __i915_refct_sgt_init might end up in a null dereference, no?!Kernel is now returning ENOMEM and also throwing a oom warning stack.With __GFP_NOWARNthe oom warning stack won't be there in the dmesg but userspace will stillget ENOMEM as expected.doh! I had missunderstand the flag. Thanks for the confirmation. Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> BTW, what email clients are you using recently?
Using the same client, Thunderbird.
it is hard to parse your responses lately. Please check if it is really sending/replying as text-only mode.
Thanks for notifying me. May be recent update changed some settings. I will check.
Nirmoy
Let me know if got your question correctly. Regards, Nirmoy >>@@ -104,7 +104,7 @@ struct i915_refct_sgt *i915_rsgt_from_mm_node(const struct drm_mm_node *node, > } > > if (sg_alloc_table(st, DIV_ROUND_UP_ULL(node->size, segment_pages), >- GFP_KERNEL)) { >+ GFP_KERNEL | __GFP_NOWARN)) { > i915_refct_sgt_put(rsgt); > return ERR_PTR(-ENOMEM); > } >@@ -178,7 +178,7 @@ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, > GEM_BUG_ON(list_empty(blocks)); > GEM_BUG_ON(!max_segment); > >- rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL); >+ rsgt = kmalloc(sizeof(*rsgt), GFP_KERNEL | __GFP_NOWARN); > if (!rsgt) > return ERR_PTR(-ENOMEM); > >@@ -190,7 +190,7 @@ struct i915_refct_sgt *i915_rsgt_from_buddy_resource(struct ttm_resource *res, > return ERR_PTR(-E2BIG); > } > >- if (sg_alloc_table(st, PFN_UP(res->size), GFP_KERNEL)) { >+ if (sg_alloc_table(st, PFN_UP(res->size), GFP_KERNEL | __GFP_NOWARN)) { > i915_refct_sgt_put(rsgt); > return ERR_PTR(-ENOMEM); > } >-- >2.42.0 References Visible links 1. https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/4936 2. mailto:andi.shyti@xxxxxxxxxxxxxxx 3. mailto:nirmoy.das@xxxxxxxxx
