[Xperia Z Q&A, Help & Troubleshooting] saddambea:
I have a C6503 (Brazil) and after updating do 4.4.2 my phone reboots many times a day.

While it's on standby it reboot.

Yesterday during a call it rebooted.

Most of the times it's a few seconds after i unlock the phone , the phone freezes the UI and reboot. But it's never a boot loop. Sometimes i can use the phone for a few hours with no reboot.

I've updated via SUS from 4.3 to 4.4.2, and also installed 3 different versions of 4.4.2 (Baltic, Nordic, and Generic Brazil) via Flashtools, and in all of the three the problem happens.

I don't know what else to try!

Can someone give me a hint of what should i try next?

The log before it reboots is as follows (got it from Android Tuner):

(just the last lines, it's not complete)

I/ 123.634399 No errors detected
I/ 123.634399 Going down for restart now
I/ 123.632446
I/ 123.632415 Restarting Linux version 3.4.0-perf-g32ce454 (BuildUser@BuildHost) (gcc version 4.7 (GCC) ) #1 SMP PREEMPT Wed Apr 9 16:52:42 2014
I/ 123.632232
I/ 123.631622
I/ 123.631622 Restarting Linux version 3.4.0-perf-g32ce454 (BuildUser@BuildHost) (gcc version 4.7 (GCC) ) #1 SMP PREEMPT Wed Apr 9 16:52:42 2014
I/ 118.622985 Rebooting in 5 seconds..
I/ 118.621856 &@panic_name@:*mpdecision*
I/ 118.120025 wcnss_8960: crash shutdown : 1
I/ 118.119628 Kernel panic - not syncing: Fatal exception in interrupt
I/ 118.119415 ---[ end trace da227214a82491bb ]---
I/ 118.119018 Code: e1a01004 e300270d e59f000c eb603280 (e7f001f2)
I/ 118.118774 [<c0249fbc>] (sys_poll+0x48/0xa8) from [<c0106120>] (ret_fast_syscall+0x0/0x30)
I/ 118.118347 [<c0249db4>] (do_sys_poll+0x1e4/0x360) from [<c0249fbc>] (sys_poll+0x48/0xa8)
I/ 118.117919 [<c023aad8>] (fput+0x210/0x224) from [<c0249db4>] (do_sys_poll+0x1e4/0x360)
I/ 118.117645 [<c0887f80>] (__irq_svc+0x40/0x70) from [<c023aad8>] (fput+0x210/0x224)
I/ 118.117218 3ba0: 00000000 00000000 c0706c60 d8c83bc0 c0249db4 c023aad8 20000013 ffffffff
I/ 118.116790 3b80: 00000002 dc75f91c dc75f900 00000000 d8c83c0c 00000000 b6b018f4 d8c83c1c
I/ 118.116394 3b60: dc75f900 00000000
I/ 118.116180 Exception stack(0xd8c83b78 to 0xd8c83bc0)
I/ 118.115783 [<c01004b8>] (gic_handle_irq+0x90/0x10c) from [<c0887f80>] (__irq_svc+0x40/0x70)
I/ 118.115356 [<c01069e4>] (handle_IRQ+0x80/0xc0) from [<c01004b8>] (gic_handle_irq+0x90/0x10c)
I/ 118.115081 [<c01824f8>] (irq_exit+0x48/0xa0) from [<c01069e4>] (handle_IRQ+0x80/0xc0)
I/ 118.114654 [<c0181f64>] (__do_softirq+0x11c/0x27c) from [<c01824f8>] (irq_exit+0x48/0xa0)
I/ 118.114257 [<c0188b88>] (run_timer_softirq+0x1fc/0x354) from [<c0181f64>] (__do_softirq+0x11c/0x27c)
I/ 118.113800 [<bf06f0b4>] (hdd_ssr_timer_cb+0x2c/0x3c [wlan]) from [<c0188b88>] (run_timer_softirq+0x1fc/0x354)

And in the middle of the log i found this too:

I/ 118.098236 Stack: (0xd8c83ac8 to 0xd8c84000)
I/ 118.098022 Process mpdecision (pid: 2012, stack limit = 0xd8c822f0)

AND in the same log:

I/ 118.028839 CPU: 0 Tainted: P W O (3.4.0-perf-g32ce454 #1)
I/ 118.027709 Modules linked in: wlan(O) texfat(PO) cfg80211
I/ 118.027465 Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
I/ 118.026885 kernel BUG at /home/hudsonslave/root/workspace/offbuild_lagan-1.3_android_matrix/HUDSON_PRODUCT/odin/HUDSON_VARIANT/user/label/CM-12/kernel/../vendor/qcom/opensource/wlan/prima/CORE/HDD/src/wlan_hdd_early_suspend.c:1805!
I/ 118.026641 ------------[ cut here ]------------
I/ 118.026123 VOS BUG in hdd_ssr_timer_cb Line 1805
I/ 118.025848 wlan: [0:F :HDD] hdd_ssr_timer_cb: HDD SSR timer expired
I/ 117.572509 wlan: [1312:E :HDD] wlan_hdd_cfg80211_scan: HDD context is not valid
I/ 117.572082 wlan: [1312:E :HDD] wlan_hdd_validate_context: LOGP in Progress. Ignore!!!
I/ 116.565490 afe_send_hw_delay: config cmd failed
I/ 116.565032 afe_callback: cmd = 0x100dc returned error = 0x3

But most of the times Wifi isn't on, neither the 3g data connection.

Got two other reboots, the log is here with different messages:

http://pastebin.com/TSgiBTdL

http://pastebin.com/xX8dMfae

In the last few hours got at least five reboots, all with no wifi connection.

This might be some hardware problem?

Help anyone, thanks!