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Message-ID: <585A7142.4070808@candelatech.com> (sfid-20161221_131045_836475_E20E7B66)
Date: Wed, 21 Dec 2016 04:10:42 -0800
From: Ben Greear <greearb@candelatech.com>
MIME-Version: 1.0
To: "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
Subject: skb truesize bug related to ath10k
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Sender: linux-wireless-owner@vger.kernel.org
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This warning is from the code below.  Anyone seen this recently?

And, what sorts of code problems can generate this type of error?  We
seem to have a way to reproduce this by bringing down and up many
station vdevs over and over again, so I can probably fix/test it if I
can understand the problem better.

We see this on QCA 9880 and 9984 NICs, so it is probably not firmware
specific issue.  We have not seen this on 4.4 kernel, but we do see it
in our 4.7.


} else {
                 if (skb_shinfo(to)->nr_frags +
                     skb_shinfo(from)->nr_frags > MAX_SKB_FRAGS)
                         return false;

                 delta = from->truesize - SKB_TRUESIZE(skb_end_offset(from));
         }

         WARN_ON_ONCE(delta < len);

Dec 18 22:40:36 ct524-9933 kernel: WARNING: CPU: 7 PID: 0 at /home/greearb/git/linux-4.7.dev.y/net/core/skbuff.c:4283 skb_try_coalesce+0x402/0x410
Dec 18 22:40:36 ct524-9933 kernel: Modules linked in: nf_conntrack_netlink nf_conntrack nfnetlink wanlink(O) nf_defrag_ipv4 macvlan pktgen fuse vfat fat 
coretemp intel_rapl x86_pkg_temp_thermal intel_powerclamp kvm_intel kvm irqbypass ath10k_pci ath10k_core ath mac80211 iTCO_wdt iTCO_vendor_support ipmi_ssif 
cfg80211 hci_uart joydev i2c_i801 btbcm btqca btintel ie31200_edac bluetooth edac_core shpchp acpi_als tpm_tis kfifo_buf pinctrl_sunrisepoint intel_lpss_acpi 
ipmi_msghandler tpm industrialio video pinctrl_intel intel_lpss acpi_power_meter sch_fq_codel nfsd auth_rpcgss nfs_acl lockd grace sunrpc 8021q garp stp llc mrp 
ast drm_kms_helper ttm drm igb i2c_algo_bit ixgbe mdio hwmon dca ptp pps_core i2c_hid i2c_core fjes efivarfs ipv6 [last unloaded: nfnetlink]
Dec 18 22:40:36 ct524-9933 kernel: CPU: 7 PID: 0 Comm: swapper/7 Tainted: G           O    4.7.10+ #46
Dec 18 22:40:36 ct524-9933 kernel: Hardware name: Supermicro Super Server/X11SSM, BIOS 1.0b 12/29/2015
Dec 18 22:40:36 ct524-9933 kernel:  0000000000000000 ffff8804779c3688 ffffffff81409351 0000000000000000
Dec 18 22:40:36 ct524-9933 kernel:  0000000000000000 ffff8804779c36c8 ffffffff81103976 000010bb779c36a8
Dec 18 22:40:36 ct524-9933 kernel:  ffff88007ce1f800 00000000000005a8 ffff8804779c3724 ffff880075b85000
Dec 18 22:40:36 ct524-9933 kernel: Call Trace:
Dec 18 22:40:36 ct524-9933 kernel:  <IRQ> [<ffffffff81409351>] dump_stack+0x63/0x82
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81103976>] __warn+0xc6/0xe0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81103a48>] warn_slowpath_null+0x18/0x20
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81760c62>] skb_try_coalesce+0x402/0x410
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817c7b79>] tcp_try_coalesce+0x39/0xa0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81761671>] ? skb_checksum+0x21/0x30
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817c8322>] tcp_queue_rcv+0x52/0x140
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817cee84>] tcp_rcv_established+0x364/0x6f0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817d9286>] tcp_v4_do_rcv+0x136/0x210
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817dab49>] tcp_v4_rcv+0x8d9/0xaf0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff8180a7f2>] ? iptable_filter_hook+0x22/0x60
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817b4bdb>] ip_local_deliver_finish+0x9b/0x1f0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817b4edb>] ip_local_deliver+0x5b/0xd0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817b4b40>] ? ip_rcv_finish+0x3f0/0x3f0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817b486a>] ip_rcv_finish+0x11a/0x3f0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817b51af>] ip_rcv+0x25f/0x380
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817b4750>] ? inet_del_offload+0x40/0x40
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81773cb4>] __netif_receive_skb_core+0x684/0xa80
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff8124925a>] ? kmem_cache_free+0x17a/0x180
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817740c3>] __netif_receive_skb+0x13/0x60
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81774133>] netif_receive_skb_internal+0x23/0x90
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff817741b7>] netif_receive_skb+0x17/0x80
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0a08d07>] ieee80211_deliver_skb+0x157/0x1b0 [mac80211]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0a0ad9a>] ieee80211_rx_handlers+0xa8a/0x2560 [mac80211]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff8155717a>] ? dma_pte_clear_level+0x14a/0x190
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0a0d077>] ieee80211_prepare_and_rx_handle+0x597/0x10a0 [mac80211]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0a0ddfa>] ieee80211_rx_napi+0x27a/0x930 [mac80211]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0c179cc>] ath10k_process_rx+0x2ac/0x4a0 [ath10k_core]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0c17bf5>] ath10k_htt_rx_h_deliver+0x35/0x80 [ath10k_core]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffffa0c1a421>] ath10k_htt_txrx_compl_task+0xc91/0xe60 [ath10k_core]
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81108afb>] tasklet_action+0x10b/0x120
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81108eca>] __do_softirq+0xca/0x2b0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff811091e9>] irq_exit+0x89/0x90
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff8102e69f>] do_IRQ+0x4f/0xd0
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff8184db42>] common_interrupt+0x82/0x82
Dec 18 22:40:36 ct524-9933 kernel:  <EOI> [<ffffffff816e8020>] ? cpuidle_enter_state+0x110/0x290
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff816e81c2>] cpuidle_enter+0x12/0x20
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81144bb5>] call_cpuidle+0x25/0x40
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff81144f72>] cpu_startup_entry+0x2b2/0x370
Dec 18 22:40:36 ct524-9933 kernel: [<ffffffff8104d8cd>] start_secondary+0x14d/0x170
Dec 18 22:40:36 ct524-9933 kernel: ---[ end trace fa9eabf037886c79 ]---


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com