3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pierre-Yves Kerbrat <pkerbrat@xxxxxxxxx> [ Upstream commit aea3fca005fb45f80869f2e8d56fd4e64c1d1fdb ] Descriptor rings were not initialized at zero when allocated When area contained garbage data, it caused skb_over_panic in e1000_clean_rx_irq (if data had E1000_RXD_STAT_DD bit set) This patch makes use of dma_zalloc_coherent to make sure the ring is memset at 0 to prevent the area from containing garbage. Following is the signature of the panic: IODDR0@0.0: skbuff: skb_over_panic: text:80407b20 len:64010 put:64010 head:ab46d800 data:ab46d842 tail:0xab47d24c end:0xab46df40 dev:eth0 IODDR0@0.0: BUG: failure at net/core/skbuff.c:105/skb_panic()! IODDR0@0.0: Kernel panic - not syncing: BUG! IODDR0@0.0: IODDR0@0.0: Process swapper/0 (pid: 0, threadinfo=81728000, task=8173cc00 ,cpu: 0) IODDR0@0.0: SP = <815a1c0c> IODDR0@0.0: Stack: 00000001 IODDR0@0.0: b2d89800 815e33ac IODDR0@0.0: ea73c040 00000001 IODDR0@0.0: 60040003 0000fa0a IODDR0@0.0: 00000002 IODDR0@0.0: IODDR0@0.0: 804540c0 815a1c70 IODDR0@0.0: b2744000 602ac070 IODDR0@0.0: 815a1c44 b2d89800 IODDR0@0.0: 8173cc00 815a1c08 IODDR0@0.0: IODDR0@0.0: 00000006 IODDR0@0.0: 815a1b50 00000000 IODDR0@0.0: 80079434 00000001 IODDR0@0.0: ab46df40 b2744000 IODDR0@0.0: b2d89800 IODDR0@0.0: IODDR0@0.0: 0000fa0a 8045745c IODDR0@0.0: 815a1c88 0000fa0a IODDR0@0.0: 80407b20 b2789f80 IODDR0@0.0: 00000005 80407b20 IODDR0@0.0: IODDR0@0.0: IODDR0@0.0: Call Trace: IODDR0@0.0: [<804540bc>] skb_panic+0xa4/0xa8 IODDR0@0.0: [<80079430>] console_unlock+0x2f8/0x6d0 IODDR0@0.0: [<80457458>] skb_put+0xa0/0xc0 IODDR0@0.0: [<80407b1c>] e1000_clean_rx_irq+0x2dc/0x3e8 IODDR0@0.0: [<80407b1c>] e1000_clean_rx_irq+0x2dc/0x3e8 IODDR0@0.0: [<804079c8>] e1000_clean_rx_irq+0x188/0x3e8 IODDR0@0.0: [<80407b1c>] e1000_clean_rx_irq+0x2dc/0x3e8 IODDR0@0.0: [<80468b48>] __dev_kfree_skb_any+0x88/0xa8 IODDR0@0.0: [<804101ac>] e1000e_poll+0x94/0x288 IODDR0@0.0: [<8046e9d4>] net_rx_action+0x19c/0x4e8 IODDR0@0.0: ... IODDR0@0.0: Maximum depth to print reached. Use kstack=<maximum_depth_to_print> To specify a custom value (where 0 means to display the full backtrace) IODDR0@0.0: ---[ end Kernel panic - not syncing: BUG! Signed-off-by: Pierre-Yves Kerbrat <pkerbrat@xxxxxxxxx> Signed-off-by: Marius Gligor <mgligor@xxxxxxxxx> Tested-by: Aaron Brown <aaron.f.brown@xxxxxxxxx> Reviewed-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/ethernet/intel/e1000e/netdev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -2330,8 +2330,8 @@ static int e1000_alloc_ring_dma(struct e { struct pci_dev *pdev = adapter->pdev; - ring->desc = dma_alloc_coherent(&pdev->dev, ring->size, &ring->dma, - GFP_KERNEL); + ring->desc = dma_zalloc_coherent(&pdev->dev, ring->size, &ring->dma, + GFP_KERNEL); if (!ring->desc) return -ENOMEM;