qlcnic: Fix scheduling while atomic bug

qlcnic: Fix scheduling while atomic bug

In the device close path, 'qlcnic_fw_destroy_ctx' and
'qlcnic_poll_rsp' call msleep. But  'qlcnic_fw_destroy_ctx' and
'qlcnic_poll_rsp' are called with 'adapter->tx_clean_lock' spin lock
held resulting in scheduling while atomic bug causing the following
trace.

I observed that the commit 012dc19a45b2b9cc2ebd14aaa401cf782c2abba4
from John Fastabend addresses a similar issue in ixgbevf driver.
Adopting the same approach used in the commit, this patch uses mdelay
to address the issue.

[79884.999115] BUG: scheduling while atomic: ip/30846/0x00000002
[79885.005562] INFO: lockdep is turned off.
[79885.009958] Modules linked in: qlcnic fuse nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE bnep bluetooth rfkill ip6table_mangle ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables iptable_nat nf_nat iptable_mangle ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack iptable_filter ip_tables dcdbas coretemp kvm_intel kvm iTCO_wdt ixgbe iTCO_vendor_support crc32c_intel ghash_clmulni_intel nfsd microcode sb_edac pcspkr edac_core dca bnx2x shpchp auth_rpcgss nfs_acl lpc_ich mfd_core mdio lockd libcrc32c wmi acpi_pad acpi_power_meter sunrpc uinput sd_mod sr_mod cdrom crc_t10dif ahci libahci libata megaraid_sas usb_storage dm_mirror dm_region_hash dm_log dm_mod [last unloaded: qlcnic]
[79885.083608] Pid: 30846, comm: ip Tainted: G        W  O 3.6.0-rc7+ #1
[79885.090805] Call Trace:
[79885.093569]  [<ffffffff816764d8>] __schedule_bug+0x68/0x76
[79885.099699]  [<ffffffff8168358e>] __schedule+0x99e/0xa00
[79885.105634]  [<ffffffff81683929>] schedule+0x29/0x70
[79885.111186]  [<ffffffff81680def>] schedule_timeout+0x16f/0x350
[79885.117724]  [<ffffffff811afb7a>] ? init_object+0x4a/0x90
[79885.123770]  [<ffffffff8107c190>] ? __internal_add_timer+0x140/0x140
[79885.130873]  [<ffffffff81680fee>] schedule_timeout_uninterruptible+0x1e/0x20
[79885.138773]  [<ffffffff8107e830>] msleep+0x20/0x30
[79885.144159]  [<ffffffffa04c7fbf>] qlcnic_issue_cmd+0xef/0x290 [qlcnic]
[79885.151478]  [<ffffffffa04c8265>] qlcnic_fw_cmd_destroy_rx_ctx+0x55/0x90 [qlcnic]
[79885.159868]  [<ffffffffa04c92fd>] qlcnic_fw_destroy_ctx+0x2d/0xa0 [qlcnic]
[79885.167576]  [<ffffffffa04bf2ed>] __qlcnic_down+0x11d/0x180 [qlcnic]
[79885.174708]  [<ffffffffa04bf6f8>] qlcnic_close+0x18/0x20 [qlcnic]
[79885.181547]  [<ffffffff8153b4c5>] __dev_close_many+0x95/0xe0
[79885.187899]  [<ffffffff8153b548>] __dev_close+0x38/0x50
[79885.193761]  [<ffffffff81545101>] __dev_change_flags+0xa1/0x180
[79885.200419]  [<ffffffff81545298>] dev_change_flags+0x28/0x70
[79885.206779]  [<ffffffff815531b8>] do_setlink+0x378/0xa00
[79885.212731]  [<ffffffff81354fe1>] ? nla_parse+0x31/0xe0
[79885.218612]  [<ffffffff815558ee>] rtnl_newlink+0x37e/0x560
[79885.224768]  [<ffffffff812cfa19>] ? selinux_capable+0x39/0x50
[79885.231217]  [<ffffffff812cbf98>] ? security_capable+0x18/0x20
[79885.237765]  [<ffffffff81555114>] rtnetlink_rcv_msg+0x114/0x2f0
[79885.244412]  [<ffffffff81551f87>] ? rtnl_lock+0x17/0x20
[79885.250280]  [<ffffffff81551f87>] ? rtnl_lock+0x17/0x20
[79885.256148]  [<ffffffff81555000>] ? __rtnl_unlock+0x20/0x20
[79885.262413]  [<ffffffff81570fc1>] netlink_rcv_skb+0xa1/0xb0
[79885.268661]  [<ffffffff81551fb5>] rtnetlink_rcv+0x25/0x40
[79885.274727]  [<ffffffff815708bd>] netlink_unicast+0x19d/0x220
[79885.281146]  [<ffffffff81570c45>] netlink_sendmsg+0x305/0x3f0
[79885.287595]  [<ffffffff8152b188>] ? sock_update_classid+0x148/0x2e0
[79885.294650]  [<ffffffff81525c2c>] sock_sendmsg+0xbc/0xf0
[79885.300600]  [<ffffffff8152600c>] __sys_sendmsg+0x3ac/0x3c0
[79885.306853]  [<ffffffff8109be23>] ? up_read+0x23/0x40
[79885.312510]  [<ffffffff816896cc>] ? do_page_fault+0x2bc/0x570
[79885.318968]  [<ffffffff81191854>] ? sys_brk+0x44/0x150
[79885.324715]  [<ffffffff811c458c>] ? fget_light+0x24c/0x520
[79885.330875]  [<ffffffff815286f9>] sys_sendmsg+0x49/0x90
[79885.336707]  [<ffffffff8168e429>] system_call_fastpath+0x16/0x1b

Signed-off-by: Narendra K <narendra_k@dell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>