[Patch v1] skbuff: Hide GFP_ATOMIC page allocation failures for dropped packets

From: Aaron Tomlin <redacted>

Failed GFP_ATOMIC allocations by the network stack result in dropped
packets, which will be received on a subsequent retransmit, and an
unnecessary, noisy warning with a kernel backtrace.

These warnings are harmless, but they still cause users to panic and
file bug reports over dropped packets. It would be better to hide the
failed allocation warnings and backtraces, and let retransmits handle
dropped packets quietly.

Signed-off-by: Aaron Tomlin <redacted>
---
 net/core/skbuff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index af9185d..02139d6 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c

@@ -236,7 +236,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
 		? skbuff_fclone_cache : skbuff_head_cache;
 
 	if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX))
-		gfp_mask |= __GFP_MEMALLOC;
+		gfp_mask |= (__GFP_MEMALLOC|__GFP_NOWARN);
 
 	/* Get the HEAD */
 	skb = kmem_cache_alloc_node(cache, gfp_mask & ~__GFP_DMA, node);

-- 
1.8.1.4

Hello.

On 26-05-2013 17:17, atomlin@redhat.com wrote:

From: Aaron Tomlin <redacted>

Failed GFP_ATOMIC allocations by the network stack result in dropped
packets, which will be received on a subsequent retransmit, and an
unnecessary, noisy warning with a kernel backtrace.

These warnings are harmless, but they still cause users to panic and
file bug reports over dropped packets. It would be better to hide the
failed allocation warnings and backtraces, and let retransmits handle
dropped packets quietly.

Signed-off-by: Aaron Tomlin <redacted>
---
  net/core/skbuff.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

   Parens not needed here.

WBR, Sergei

On Sun, 2013-05-26 at 20:28 +0400, Sergei Shtylyov wrote:

On 26-05-2013 17:17, atomlin@redhat.com wrote:

quoted

Failed GFP_ATOMIC allocations by the network stack result in dropped
packets, which will be received on a subsequent retransmit, and an
unnecessary, noisy warning with a kernel backtrace.

quoted

These warnings are harmless, but they still cause users to panic and
file bug reports over dropped packets. It would be better to hide the
failed allocation warnings and backtraces, and let retransmits handle
dropped packets quietly.

quoted

diff --git a/net/core/skbuff.c b/net/core/skbuff.c

[]

quoted

@@ -236,7 +236,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
  		? skbuff_fclone_cache : skbuff_head_cache;

  	if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX))
-		gfp_mask |= __GFP_MEMALLOC;
+		gfp_mask |= (__GFP_MEMALLOC|__GFP_NOWARN);

    Parens not needed here.

Maybe add a pr_debug before the goto out instead.

Hello.

On 26-05-2013 20:28, Sergei Shtylyov wrote:

quoted

From: Aaron Tomlin <redacted>

quoted

Failed GFP_ATOMIC allocations by the network stack result in dropped
packets, which will be received on a subsequent retransmit, and an
unnecessary, noisy warning with a kernel backtrace.

quoted

These warnings are harmless, but they still cause users to panic and
file bug reports over dropped packets. It would be better to hide the
failed allocation warnings and backtraces, and let retransmits handle
dropped packets quietly.

quoted

Signed-off-by: Aaron Tomlin <redacted>
---
  net/core/skbuff.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

quoted

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index af9185d..02139d6 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c

@@ -236,7 +236,7 @@ struct sk_buff *__alloc_skb(unsigned int size,

gfp_t gfp_mask,
          ? skbuff_fclone_cache : skbuff_head_cache;

      if (sk_memalloc_socks() && (flags & SKB_ALLOC_RX))
-        gfp_mask |= __GFP_MEMALLOC;
+        gfp_mask |= (__GFP_MEMALLOC|__GFP_NOWARN);

    Parens not needed here.

   And add spaces around | please, to be consistent with other code.

WBR, Sergei