Linux 3.14 hang at reboot

[emilmyhrman]

Using 3.14 kernel and Lollipop 5.1 we sometimes get a hang at "reboot bootloader" command.

I was able to capture this with JTAG.

#0  v7wbi_flush_kern_tlb_range () at arch/arm/mm/tlb-v7.S:84

#1  0xc00160a0 in flush_tlb_kernel_range (start=<optimized out>, end=<optimized out>) at arch/arm/kernel/smp_tlb.c:199

#2  0xc0124fcc in __purge_vmap_area_lazy (start=<optimized out>, end=0xce06dd8c, sync=<optimized out>, force_flush=<optimized out>) at mm/vmalloc.c:636

#3  0xc0125238 in try_purge_vmap_area_lazy () at mm/vmalloc.c:655

#4  free_vmap_area_noflush (va=<optimized out>) at mm/vmalloc.c:678

#5  0xc01253c0 in free_unmap_vmap_area_noflush (va=<optimized out>) at mm/vmalloc.c:688

#6  free_unmap_vmap_area (va=0xc44b3940) at mm/vmalloc.c:697

#7  0xc0126c28 in remove_vm_area (addr=<optimized out>) at mm/vmalloc.c:1419

#8  0xc0126c78 in __vunmap (addr=0xbf00a000, deallocate_pages=-364908544) at mm/vmalloc.c:1438

#9  0xc0126ea8 in vunmap (addr=0xbf00a000) at mm/vmalloc.c:1513

#10 0xc001d760 in __iounmap (io_addr=<optimized out>) at arch/arm/mm/ioremap.c:429

#11 0xc001d6c4 in __arm_iounmap (io_addr=<optimized out>) at arch/arm/mm/ioremap.c:436

#12 0xc00216bc in do_switch_fastboot () at arch/arm/mach-imx/system.c:111

#13 0xc0021830 in arch_reset_special_mode (mode=<optimized out>, cmd=<optimized out>) at arch/arm/mach-imx/system.c:121

#14 mxc_restart (mode=<optimized out>, cmd=0xce06de88 "bootloader") at arch/arm/mach-imx/system.c:137

#15 0xc000fbf0 in machine_restart (cmd=0xce06de88 "bootloader") at arch/arm/kernel/process.c:292

#16 0xc005f34c in kernel_restart (cmd=0xce06de88 "bootloader") at kernel/reboot.c:143

#17 0xc005f68c in SYSC_reboot (arg=<optimized out>, cmd=<optimized out>, magic2=<optimized out>, magic1=<optimized out>) at kernel/reboot.c:265

#18 SyS_reboot (magic1=-18751827, magic2=<optimized out>, cmd=<optimized out>, arg=-1095332841) at kernel/reboot.c:199

Any idea what is going on?

[CarlosCasillas]

Hi Emil,

We are internally reviewing your case.

I will post an update as soon as having news.

Best regards!

/Carlos

[CarlosCasillas]

Hi Emil,

Can you provide more information? Where do you reboot? What board?

It is best to provide all the log.

Best regards!

/Carlos

[emilmyhrman]

Sorry for the late reply.

The board is a custom imx6DL, running Android 5.1.1. This occured when rebooting, e.g. from command line "reboot bootloader".

I never found out why, but worked around this by removing the "iounmap(addr);" in do_switch_recovery (arch/arm/mach-imx/system.c).