shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-09 20:32:04 +09:00
Code Issues Packages Projects Releases Wiki Activity

net: netpoll: flush skb pool during cleanup

Browse Source 
[ Upstream commit 6c59f16f1770481a6ee684720ec55b1e38b3a4b2 ]

The netpoll subsystem maintains a pool of 32 pre-allocated SKBs per
instance, but these SKBs are not freed when the netpoll user is brought
down. This leads to memory waste as these buffers remain allocated but
unused.

Add skb_pool_flush() to properly clean up these SKBs when netconsole is
terminated, improving memory efficiency.

Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20241114-skb_buffers_v2-v3-2-9be9f52a8b69@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 49c8d2c1f94c ("net: netpoll: fix incorrect refcount handling causing incorrect cleanup")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Breno Leitao
2025-11-20 14:56:55 -05:00
committed by Greg Kroah-Hartman
parent dc67d67a99
commit a3a476cb65
1 changed files with 13 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
net/core/netpoll.c
View File

@@ -538,6 +538,14 @@ static int netpoll_parse_ip_addr(const char *str, union inet_addr *addr)
return -1;
}
static void skb_pool_flush(struct netpoll *np)
{
struct sk_buff_head *skb_pool;
skb_pool = &np->skb_pool;
skb_queue_purge_reason(skb_pool, SKB_CONSUMED);
}
int netpoll_parse_options(struct netpoll *np, char *opt)
{
char *cur=opt, *delim;
@@ -786,7 +794,7 @@ put_noaddr:
err = __netpoll_setup(np, ndev);
if (err)
goto put;
goto flush;
rtnl_unlock();
/* Make sure all NAPI polls which started before dev->npinfo
@@ -797,6 +805,8 @@ put_noaddr:
return 0;
flush:
skb_pool_flush(np);
put:
DEBUG_NET_WARN_ON_ONCE(np->dev);
if (ip_overwritten)
@@ -844,6 +854,8 @@ void __netpoll_cleanup(struct netpoll *np)
call_rcu(&npinfo->rcu, rcu_cleanup_netpoll_info);
} else
RCU_INIT_POINTER(np->dev->npinfo, NULL);
skb_pool_flush(np);
}
EXPORT_SYMBOL_GPL(__netpoll_cleanup);