Re: [PATCH] MIPS: IRQ Stack: Unwind IRQ stack onto task stack

[Matt Redfearn]

Hi Jason,


On 04/04/17 12:58, Jason A. Donenfeld wrote:
> This indeed is useful. Out of curiosity, are other archs using a
> similar technique? In anycase,
>
> Acked-by: Jason A. Donenfeld <Jason@xxxxxxxxx>

Yes, at least x86 and ARM64 do the same thing (probably more)

x86 saves the previous stack pointer on the IRQ stack in 
http://lxr.free-electrons.com/source/arch/x86/kernel/irq_32.c#L70
which is then unwound in 
http://lxr.free-electrons.com/source/arch/x86/kernel/dumpstack.c#L51

ARM64 saves the task SP in 
http://lxr.free-electrons.com/source/arch/arm64/kernel/entry.S#L249
And unwinds it in 
http://lxr.free-electrons.com/source/arch/arm64/kernel/traps.c#L140

Thanks,
Matt