bnxt: make sure we return pages to the pool
Jakub Kicinski
maintainerPATCH 1/1 bnxt: make sure we return pages to the pool
Before the commit under Fixes the page would have been released from the pool before the napi_alloc_skb() call, so normal page freeing was fine (released page == no longer in the pool).
After the change we just mark the page for recycling so it's still in the pool if the skb alloc fails, we need to recycle.
Same commit added the same bug in the new bnxt_rx_multi_page_skb().
--- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
drivers/net/ethernet/broadcom/bnxt/bnxt.c +2 -2
@@ -993,7 +993,7 @@ static struct sk_buff *bnxt_rx_multi_page_skb(struct bnxt *bp, DMA_ATTR_WEAK_ORDERING); skb =build_skb (page_address (page),PAGE_SIZE );if (!skb) { -__free_page (page); +page_pool_recycle_direct (rxr->page_pool, page);return NULL ; }skb_mark_for_recycle (skb);
@@ -1031,7 +1031,7 @@ static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp, skb =napi_alloc_skb (&rxr->bnapi->napi, payload);if (!skb) { -__free_page (page); +page_pool_recycle_direct (rxr->page_pool, page);return NULL ; }
Signature · 1 line
2.38.1
Quoted 8 lines · Jakub Kicinski
Before the commit under Fixes the page would have been released from the pool before the
napi_alloc_skb()call, so normal page freeing was fine (released page == no longer in the pool).After the change we just mark the page for recycling so it's still in the pool if the skb alloc fails, we need to recycle.
Same commit added the same bug in the new
bnxt_rx_multi_page_skb().
Good catch, thank you.
Quoted 2 lines
Fixes 1dc4c557bfed ("bnxt: adding bnxt_xdp_build_skb to build skb from multibuffer xdp_buff")Signed-off-by Jakub Kicinski <[email protected]>
Quoted 29 lines
--- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)drivers/net/ethernet/broadcom/bnxt/bnxt.c +2
-2@@ -993,7 +993,7 @@ static struct sk_buff *bnxt_rx_multi_page_skb(struct bnxt *bp, DMA_ATTR_WEAK_ORDERING); skb =build_skb (page_address (page),PAGE_SIZE );if (!skb) { -__free_page (page); +page_pool_recycle_direct (rxr->page_pool, page);return NULL ; }skb_mark_for_recycle (skb);@@ -1031,7 +1031,7 @@ static struct sk_buff *bnxt_rx_page_skb(struct bnxt *bp, skb =napi_alloc_skb (&rxr->bnapi->napi, payload);if (!skb) { -__free_page (page); +page_pool_recycle_direct (rxr->page_pool, page);return NULL ; }Signature · 1 line
2.38.1
This patch was applied to netdev/net.git (master) by Jakub Kicinski <[email protected]>:
Hello:
This patch was applied to netdev/net.git (master)
by Jakub Kicinski <[email protected]>:
Quoted 8 lines · On Tue, 10 Jan 2023 20:25:47 -0800 you wrote:
Before the commit under Fixes the page would have been released from the pool before the
napi_alloc_skb()call, so normal page freeing was fine (released page == no longer in the pool).After the change we just mark the page for recycling so it's still in the pool if the skb alloc fails, we need to recycle.
[...]
Here is the summary with links:
- [net] bnxt: make sure we return pages to the pool
https://git.kernel.org/netdev/net/c/97f5e03a4a27
You are awesome, thank you!
Signature · 2 lines
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