4.18-stable review patch. If anyone has any objections, please let me know.
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From: Subash Abhinov Kasiviswanathan subashab@codeaurora.org
[ Upstream commit 6392ff3c8e4c23d0a09b0ae9f94feb3effed490b ]
The incoming skb needs to be reallocated in case the headroom is not sufficient to add the MAP header. This allocation needs to be atomic otherwise it results in the following splat
[32805.801456] BUG: sleeping function called from invalid context [32805.841141] Internal error: Oops - BUG: 0 [#1] PREEMPT SMP [32805.904773] task: ffffffd7c5f62280 task.stack: ffffff80464a8000 [32805.910851] pc : ___might_sleep+0x180/0x188 [32805.915143] lr : ___might_sleep+0x180/0x188 [32806.131520] Call trace: [32806.134041] ___might_sleep+0x180/0x188 [32806.137980] __might_sleep+0x50/0x84 [32806.141653] __kmalloc_track_caller+0x80/0x3bc [32806.146215] __kmalloc_reserve+0x3c/0x88 [32806.150241] pskb_expand_head+0x74/0x288 [32806.154269] rmnet_egress_handler+0xb0/0x1d8 [32806.162239] rmnet_vnd_start_xmit+0xc8/0x13c [32806.166627] dev_hard_start_xmit+0x148/0x280 [32806.181181] sch_direct_xmit+0xa4/0x198 [32806.185125] __qdisc_run+0x1f8/0x310 [32806.188803] net_tx_action+0x23c/0x26c [32806.192655] __do_softirq+0x220/0x408 [32806.196420] do_softirq+0x4c/0x70
Fixes: ceed73a2cf4a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation") Signed-off-by: Subash Abhinov Kasiviswanathan subashab@codeaurora.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c +++ b/drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c @@ -147,7 +147,7 @@ static int rmnet_map_egress_handler(stru }
if (skb_headroom(skb) < required_headroom) { - if (pskb_expand_head(skb, required_headroom, 0, GFP_KERNEL)) + if (pskb_expand_head(skb, required_headroom, 0, GFP_ATOMIC)) return -ENOMEM; }