On Tue, Apr 30, 2013 at 12:26 PM, Bing Zhao <bzhao@xxxxxxxxxxx> wrote:
> Please test the revision attached with this e-mail.
It works with the original test case. Thanks. In that environment, for
whatever reason, scan_delay_fn is not triggered.
However, I think we both agree that scan_delay_fn can (and will)
'legally' execute during the above test (and you did mention earlier
that in your env it is being called). I can see that some conditions
must be met for this to happen, defined in mwifiex_ret_802_11_scan().
To simplify my testing I just "relaxed" those conditions to be:
- } else if (!mwifiex_wmm_lists_empty(adapter) &&
- (priv->scan_request && (priv->scan_request->flags &
- NL80211_SCAN_FLAG_LOW_PRIORITY))) {
+ } else if (1) {
Now it always triggers. A good way to get some solid testing of this codepath.
And as I suspected, running my test now causes an immediate kernel crash.
bash-4.2# bash test.sh
mwifiex_sdio mmc0:0001:1: WLAN FW already running! Skip FW dnld
lis3lv02d_i2c 4-0019: Failed to get supply 'Vdd': -517
i2c 4-0019: Driver lis3lv02d_i2c requests probe deferral
mwifiex_sdio mmc0:0001:1: WLAN FW is active
mwifiex_sdio mmc0:0001:1: ignoring F/W country code US
mwifiex_sdio mmc0:0001:1: driver_version = mwifiex 1.0 (14.66.9.p96)
systemd-udevd[474]: renamed network interface mlan0 to eth0
mwifiex_sdio mmc0:0001:1: info: mwifiex_ret_802_11_scan: deferring scan
mwifiex_sdio mmc0:0001:1: info: mwifiex_ret_802_11_scan: deferring scan
eth0 Failed to read scan data : No such device
Unable to handle kernel paging request at virtual address 00100100
pgd = c0004000
[00100100] *pgd=00000000
Internal error: Oops: 15 [#1] PREEMPT ARM
Modules linked in: [last unloaded: mwifiex_sdio]
CPU: 0 Not tainted (3.8.0-00021-gd431a65-dirty #992)
PC is at scan_delay_timer_fn+0x1dc/0x2a0
LR is at call_timer_fn.isra.36+0x2c/0x94
pc : [<c021b2a0>] lr : [<c002a158>] psr: 600f0193
sp : c054fe50 ip : c054fe78 fp : c054fe74
r10: 3fa6bf3c r9 : 00200000 r8 : c0594080
r7 : c021b0c4 r6 : 00100100 r5 : ed4fc000 r4 : edbce000
r3 : c054e000 r2 : 600f0113 r1 : 00000103 r0 : 0000000a
Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 10c5387d Table: 2d888059 DAC: 00000015
Process swapper (pid: 0, stack limit = 0xc054e240)
Stack: (0xc054fe50 to 0xc0550000)
fe40: c054e000 00000102 ed4fc000 c021b0c4
fe60: c0594080 3fa6bf3c c054fe9c c054fe78 c002a158 c021b0d0 0000000d 00000001
fe80: c0594200 c054e000 ed4fc000 c021b0c4 c054fec4 c054fea0 c002a36c c002a138
fea0: c054fea0 c054fea0 00000001 c05940c8 c054e000 00000102 c054ff0c c054fec8
fec0: c0023de8 c002a1cc 00000000 ee004740 c054feec 00000004 00000001 0000000a
fee0: c054ff04 0000000d 00000000 fe282104 c054ff7c 00004059 562f5842 00000000
ff00: c054ff1c c054ff10 c00241a0 c0023d48 c054ff34 c054ff20 c000fa98 c0024160
ff20: c000fcac 600f0013 c054ff44 c054ff38 c0008250 c000fa38 c054ffa4 c054ff48
ff40: c000e6cc c000824c 00000000 c055dbd8 00000000 00000000 c054e000 c0581348
ff60: c0531198 c15f5a00 00004059 562f5842 00000000 c054ffa4 c054ff90 c054ff90
ff80: c000fb4c c000fcac 600f0013 ffffffff 00000002 00000000 c054ffbc c054ffa8
ffa0: c03da988 c000fc5c c055acd0 c05560d8 c054fff4 c054ffc0 c050f7ec c03da924
ffc0: ffffffff ffffffff c050f2dc 00000000 00000000 c0531198 10c5387d c0556024
ffe0: c0531194 c05598e4 00000000 c054fff8 00008074 c050f558 00000000 00000000
Backtrace:
[<c021b0c4>] (scan_delay_timer_fn+0x0/0x2a0) from [<c002a158>]
(call_timer_fn.isra.36+0x2c/0x94)
[<c002a12c>] (call_timer_fn.isra.36+0x0/0x94) from [<c002a36c>]
(run_timer_softirq+0x1ac/0x22c)
r7:c021b0c4 r6:ed4fc000 r5:c054e000 r4:c0594200
[<c002a1c0>] (run_timer_softirq+0x0/0x22c) from [<c0023de8>]
(__do_softirq+0xac/0x174)
r7:00000102 r6:c054e000 r5:c05940c8 r4:00000001
[<c0023d3c>] (__do_softirq+0x0/0x174) from [<c00241a0>] (irq_exit+0x4c/0xb0)
[<c0024154>] (irq_exit+0x0/0xb0) from [<c000fa98>] (handle_IRQ+0x6c/0x8c)
[<c000fa2c>] (handle_IRQ+0x0/0x8c) from [<c0008250>] (asm_do_IRQ+0x10/0x14)
r5:600f0013 r4:c000fcac
[<c0008240>] (asm_do_IRQ+0x0/0x14) from [<c000e6cc>] (__irq_svc+0x4c/0x94)
Exception stack(0xc054ff48 to 0xc054ff90)
ff40: 00000000 c055dbd8 00000000 00000000 c054e000 c0581348
ff60: c0531198 c15f5a00 00004059 562f5842 00000000 c054ffa4 c054ff90 c054ff90
ff80: c000fb4c c000fcac 600f0013 ffffffff
[<c000fc50>] (cpu_idle+0x0/0xa4) from [<c03da988>] (rest_init+0x70/0x88)
r5:00000000 r4:00000002
[<c03da918>] (rest_init+0x0/0x88) from [<c050f7ec>] (start_kernel+0x2a0/0x2f0)
r4:c05560d8 r3:c055acd0
[<c050f54c>] (start_kernel+0x0/0x2f0) from [<00008074>] (0x8074)
Code: e5931004 e2811001 e5831004 e5946a5c (e8960003)
---[ end trace 5842e4d79510ea17 ]---
Kernel panic - not syncing: Fatal exception in interrupt
I suspect this crash also existed before your patch, just I was not
testing scan_delay_fn before. Maybe you prefer to deal with it as a
separate issue.
Daniel
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
