Sabrina Dubroca 08e8331654 e1000: add dummy allocator to fix race condition between mtu change and netpoll ... There is a race condition between e1000_change_mtu's cleanups and netpoll, when we change the MTU across jumbo size: Changing MTU frees all the rx buffers: e1000_change_mtu -> e1000_down -> e1000_clean_all_rx_rings -> e1000_clean_rx_ring Then, close to the end of e1000_change_mtu: pr_info -> ... -> netpoll_poll_dev -> e1000_clean -> e1000_clean_rx_irq -> e1000_alloc_rx_buffers -> e1000_alloc_frag And when we come back to do the rest of the MTU change: e1000_up -> e1000_configure -> e1000_configure_rx -> e1000_alloc_jumbo_rx_buffers alloc_jumbo finds the buffers already != NULL, since data (shared with page in e1000_rx_buffer->rxbuf) has been re-alloc'd, but it's garbage, or at least not what is expected when in jumbo state. This results in an unusable adapter (packets don't get through), and a NULL pointer dereference on the next call to e1000_clean_rx_ring (other mtu change, link down, shutdown): BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81194d6e>] put_compound_page+0x7e/0x330 [...] Call Trace: [<ffffffff81195445>] put_page+0x55/0x60 [<ffffffff815d9f44>] e1000_clean_rx_ring+0x134/0x200 [<ffffffff815da055>] e1000_clean_all_rx_rings+0x45/0x60 [<ffffffff815df5e0>] e1000_down+0x1c0/0x1d0 [<ffffffff811e2260>] ? deactivate_slab+0x7f0/0x840 [<ffffffff815e21bc>] e1000_change_mtu+0xdc/0x170 [<ffffffff81647050>] dev_set_mtu+0xa0/0x140 [<ffffffff81664218>] do_setlink+0x218/0xac0 [<ffffffff814459e9>] ? nla_parse+0xb9/0x120 [<ffffffff816652d0>] rtnl_newlink+0x6d0/0x890 [<ffffffff8104f000>] ? kvm_clock_read+0x20/0x40 [<ffffffff810a2068>] ? sched_clock_cpu+0xa8/0x100 [<ffffffff81663802>] rtnetlink_rcv_msg+0x92/0x260 By setting the allocator to a dummy version, netpoll can't mess up our rx buffers. The allocator is set back to a sane value in e1000_configure_rx. Fixes: edbbb3ca10 ("e1000: implement jumbo receive with partial descriptors") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>		2015-03-06 02:47:10 -08:00
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e1000	e1000: add dummy allocator to fix race condition between mtu change and netpoll	2015-03-06 02:47:10 -08:00
e1000e	e1000e: remove calls to ioremap/unmap for NVM addr	2015-03-06 02:47:08 -08:00
fm10k	fm10k: Resolve various spelling errors and checkpatch warnings	2015-03-03 01:07:23 -08:00
i40e	i40e: Fix mismatching type for ioremap_len	2015-03-05 22:11:38 -05:00
i40evf	i40e/i40evf: Version bump	2015-03-05 08:17:28 -08:00
igb	igb: Make arrays on stack static const to avoid reallocation	2015-03-06 02:47:09 -08:00
igbvf	igbvf: cleanup msleep() and min/max() usage	2015-02-23 17:11:54 -08:00
ixgb	net: rename vlan_tx_* helpers since "tx" is misleading there	2015-01-13 17:51:08 -05:00
ixgbe	ethernet: Use eth_<foo>_addr instead of memset	2015-03-03 17:01:36 -05:00
ixgbevf	ixgbevf: combine all of the tasks into a single service task	2015-02-05 19:58:45 -08:00
e100.c	e100: fix typo in MDI/MDI-X eeprom check in e100_phy_init	2014-12-31 11:55:40 -08:00
Kconfig	i40e: Fix dependencies in the i40e driver on configfs	2015-03-03 16:52:41 -05:00
Makefile	fm10k: Add skeletal frame for Intel(R) FM10000 Ethernet Switch Host Interface Driver	2014-09-23 03:59:13 -07:00