Re: [PATCH v10 01/11] arm64: Select STACKTRACE in arch/arm64/Kconfig

Mark Rutland
2021-10-22T18:02:53Z

Hi Madhavan,

Apolgoies for the delay in getting round to this.

On Thu, Oct 14, 2021 at 09:58:37PM -0500, madvenka@linux.microsoft.com wrote:
> From: "Madhavan T. Venkataraman" <madvenka@linux.microsoft.com>
>
> Currently, there are multiple functions in ARM64 code that walk the
> stack using start_backtrace() and unwind_frame() or start_backtrace()
> and walk_stackframe(). They should all be converted to use
> arch_stack_walk(). This makes maintenance easier.
>
> To do that, arch_stack_walk() must always be defined. arch_stack_walk()
> is within #ifdef CONFIG_STACKTRACE. So, select STACKTRACE in
> arch/arm64/Kconfig.

I'd prefer if we could decouple ARCH_STACKWALK from STACKTRACE, so that
we don't have to expose /proc/*/stack unconditionally, which Peter
Zijlstra has a patch for:

https://lore.kernel.org/lkml/20211022152104.356586621@infradead.org/

... but regardless the rest of the series looks pretty good, so I'll go
review that, and we can figure out how to queue the bits and pieces in
the right order.

Thanks,
Mark.

>
> Signed-off-by: Madhavan T. Venkataraman <madvenka@linux.microsoft.com>
> ---
> arch/arm64/Kconfig | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index fdcd54d39c1e..bfb0ce60d820 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -35,6 +35,7 @@ config ARM64
> select ARCH_HAS_SET_DIRECT_MAP
> select ARCH_HAS_SET_MEMORY
> select ARCH_STACKWALK
> + select STACKTRACE
> select ARCH_HAS_STRICT_KERNEL_RWX
> select ARCH_HAS_STRICT_MODULE_RWX
> select ARCH_HAS_SYNC_DMA_FOR_DEVICE
> --
> 2.25.1
>