Re: [PATCH 15/20] ARM/hw_breakpoint: Convert to hotplug state machine
From: Linus Walleij
Date: Mon Jan 02 2017 - 15:16:32 EST
On Mon, Jan 2, 2017 at 4:00 PM, Russell King - ARM Linux
<linux@xxxxxxxxxxxxxxx> wrote:
> On Mon, Jan 02, 2017 at 03:34:32PM +0100, Linus Walleij wrote:
>> in the first line of arch_hw_breakpoint_init() in
>> arch/arm/kernel/hw_breakpoint.c
>>
>> I suspect that is not an accepable solution ...
>>
>> It hangs at PC is at write_wb_reg+0x20c/0x330
>> Which is c03101dc, and looks like this in objdump -d:
>>
>> c031020c: ee001eba mcr 14, 0, r1, cr0, cr10, {5}
>> c0310210: eaffffb3 b c03100e4 <write_wb_reg+0x114>
>
> ... and this is several instructions after the address you mention above.
> Presumably c03101dc is accessing a higher numbered register?
Ah sorry. It looks like this:
c03101dc: ee001ed0 mcr 14, 0, r1, cr0, cr0, {6}
c03101e0: eaffffbf b c03100e4 <write_wb_reg+0x114>
c03101e4: ee001ebf mcr 14, 0, r1, cr0, cr15, {5}
c03101e8: eaffffbd b c03100e4 <write_wb_reg+0x114>
c03101ec: ee001ebe mcr 14, 0, r1, cr0, cr14, {5}
c03101f0: eaffffbb b c03100e4 <write_wb_reg+0x114>
c03101f4: ee001ebd mcr 14, 0, r1, cr0, cr13, {5}
c03101f8: eaffffb9 b c03100e4 <write_wb_reg+0x114>
Yours,
Linus Walleij