This is a note to let you know that I've just added the patch titled
net: add SKB_HEAD_ALIGN() helper
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-add-skb_head_align-helper.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From stable-owner@xxxxxxxxxxxxxxx Fri Sep 15 20:23:16 2023
From: Ajay Kaher <akaher@xxxxxxxxxx>
Date: Fri, 15 Sep 2023 23:51:02 +0530
Subject: net: add SKB_HEAD_ALIGN() helper
To: stable@xxxxxxxxxxxxxxx
Cc: davem@xxxxxxxxxxxxx, edumazet@xxxxxxxxxx, kuba@xxxxxxxxxx, pabeni@xxxxxxxxxx, alexanderduyck@xxxxxx, soheil@xxxxxxxxxx, netdev@xxxxxxxxxxxxxxx, namit@xxxxxxxxxx, amakhalov@xxxxxxxxxx, vsirnapalli@xxxxxxxxxx, er.ajay.kaher@xxxxxxxxx, akaher@xxxxxxxxxx
Message-ID: <1694802065-1821-2-git-send-email-akaher@xxxxxxxxxx>
From: Eric Dumazet <edumazet@xxxxxxxxxx>
commit 115f1a5c42bdad9a9ea356fc0b4a39ec7537947f upstream.
We have many places using this expression:
SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
Use of SKB_HEAD_ALIGN() will allow to clean them.
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Acked-by: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx>
Acked-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Reviewed-by: Alexander Duyck <alexanderduyck@xxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
[Ajay: Regenerated the patch for v6.1.y]
Signed-off-by: Ajay Kaher <akaher@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/linux/skbuff.h | 8 ++++++++
net/core/skbuff.c | 18 ++++++------------
2 files changed, 14 insertions(+), 12 deletions(-)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -261,6 +261,14 @@
#define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES)
#define SKB_WITH_OVERHEAD(X) \
((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
+
+/* For X bytes available in skb->head, what is the minimal
+ * allocation needed, knowing struct skb_shared_info needs
+ * to be aligned.
+ */
+#define SKB_HEAD_ALIGN(X) (SKB_DATA_ALIGN(X) + \
+ SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
+
#define SKB_MAX_ORDER(X, ORDER) \
SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
#define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -504,8 +504,7 @@ struct sk_buff *__alloc_skb(unsigned int
* aligned memory blocks, unless SLUB/SLAB debug is enabled.
* Both skb->head and skb_shared_info are cache line aligned.
*/
- size = SKB_DATA_ALIGN(size);
- size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ size = SKB_HEAD_ALIGN(size);
osize = kmalloc_size_roundup(size);
data = kmalloc_reserve(osize, gfp_mask, node, &pfmemalloc);
if (unlikely(!data))
@@ -578,8 +577,7 @@ struct sk_buff *__netdev_alloc_skb(struc
goto skb_success;
}
- len += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
- len = SKB_DATA_ALIGN(len);
+ len = SKB_HEAD_ALIGN(len);
if (sk_memalloc_socks())
gfp_mask |= __GFP_MEMALLOC;
@@ -678,8 +676,7 @@ struct sk_buff *__napi_alloc_skb(struct
data = page_frag_alloc_1k(&nc->page_small, gfp_mask);
pfmemalloc = NAPI_SMALL_PAGE_PFMEMALLOC(nc->page_small);
} else {
- len += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
- len = SKB_DATA_ALIGN(len);
+ len = SKB_HEAD_ALIGN(len);
data = page_frag_alloc(&nc->page, len, gfp_mask);
pfmemalloc = nc->page.pfmemalloc;
@@ -1837,8 +1834,7 @@ int pskb_expand_head(struct sk_buff *skb
if (skb_pfmemalloc(skb))
gfp_mask |= __GFP_MEMALLOC;
- size = SKB_DATA_ALIGN(size);
- size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ size = SKB_HEAD_ALIGN(size);
size = kmalloc_size_roundup(size);
data = kmalloc_reserve(size, gfp_mask, NUMA_NO_NODE, NULL);
if (!data)
@@ -6204,8 +6200,7 @@ static int pskb_carve_inside_header(stru
if (skb_pfmemalloc(skb))
gfp_mask |= __GFP_MEMALLOC;
- size = SKB_DATA_ALIGN(size);
- size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ size = SKB_HEAD_ALIGN(size);
size = kmalloc_size_roundup(size);
data = kmalloc_reserve(size, gfp_mask, NUMA_NO_NODE, NULL);
if (!data)
@@ -6323,8 +6318,7 @@ static int pskb_carve_inside_nonlinear(s
if (skb_pfmemalloc(skb))
gfp_mask |= __GFP_MEMALLOC;
- size = SKB_DATA_ALIGN(size);
- size += SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
+ size = SKB_HEAD_ALIGN(size);
size = kmalloc_size_roundup(size);
data = kmalloc_reserve(size, gfp_mask, NUMA_NO_NODE, NULL);
if (!data)
Patches currently in stable-queue which might be from stable-owner@xxxxxxxxxxxxxxx are
queue-6.1/net-add-skb_head_align-helper.patch
queue-6.1/io_uring-don-t-set-affinity-on-a-dying-sqpoll-thread.patch
queue-6.1/net-remove-osize-variable-in-__alloc_skb.patch
queue-6.1/io_uring-always-lock-in-io_apoll_task_func.patch
queue-6.1/net-factorize-code-in-kmalloc_reserve.patch
queue-6.1/io_uring-revert-io_uring-fix-multishot-accept-ordering.patch
queue-6.1/io_uring-net-don-t-overflow-multishot-accept.patch
queue-6.1/io_uring-sqpoll-fix-io-wq-affinity-when-ioring_setup_sqpoll-is-used.patch
queue-6.1/io_uring-break-out-of-iowq-iopoll-on-teardown.patch
queue-6.1/net-deal-with-integer-overflows-in-kmalloc_reserve.patch
