[PATCH] dma/pool: respect __GFP_NOWARN in dma_alloc_from_pool()

[PATCH] dma/pool: respect __GFP_NOWARN in dma_alloc_from_pool()

[Sai Sree Kartheek Adivi]

Currently, dma_alloc_from_pool() unconditionally warns and dumps a stack
trace when an allocation fails.

This prevents callers from using the __GFP_NOWARN flag to suppress error
messages, breaking the expectation that this flag will silence
allocation failure logs.

Align dma_pool behaviour with other core allocators by checking for
__GFP_NOWARN before issuing the warning.

Fixes: 9420139f516d ("dma-pool: fix coherent pool allocations for IOMMU mappings")
Signed-off-by: Sai Sree Kartheek Adivi <s-adivi@ti.com>
---
 kernel/dma/pool.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c
index 26392badc36b..40dc2ab9915f 100644
--- a/kernel/dma/pool.c
+++ b/kernel/dma/pool.c
@@ -276,7 +276,8 @@ struct page *dma_alloc_from_pool(struct device *dev, size_t size,
 			return page;
 	}
 
-	WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev));
+	if (!(gfp & __GFP_NOWARN))
+		WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev));
 	return NULL;
 }
 
-- 
2.34.1

Re: [PATCH] dma/pool: respect __GFP_NOWARN in dma_alloc_from_pool()

[Leon Romanovsky]

On Sun, Jan 11, 2026 at 07:11:50AM +0530, Sai Sree Kartheek Adivi wrote:
> Currently, dma_alloc_from_pool() unconditionally warns and dumps a stack
> trace when an allocation fails.
> 
> This prevents callers from using the __GFP_NOWARN flag to suppress error
> messages, breaking the expectation that this flag will silence
> allocation failure logs.
> 
> Align dma_pool behaviour with other core allocators by checking for
> __GFP_NOWARN before issuing the warning.
> 
> Fixes: 9420139f516d ("dma-pool: fix coherent pool allocations for IOMMU mappings")
> Signed-off-by: Sai Sree Kartheek Adivi <s-adivi@ti.com>
> ---
>  kernel/dma/pool.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c
> index 26392badc36b..40dc2ab9915f 100644
> --- a/kernel/dma/pool.c
> +++ b/kernel/dma/pool.c
> @@ -276,7 +276,8 @@ struct page *dma_alloc_from_pool(struct device *dev, size_t size,
>  			return page;
>  	}
>  
> -	WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev));
> +	if (!(gfp & __GFP_NOWARN))
> +		WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev));

WARN(!(gfp & __GFP_NOWARN), "Failed to get suitable pool for %s\n", dev_name(dev));

Thanks

>  	return NULL;
>  }
>  
> -- 
> 2.34.1
> 
>