Re: [PATCH v4 3/8] arm64: entry: add unwind info for various kernel entries

From: Jens Remus

Date: Wed Apr 22 2026 - 10:19:26 EST


On 4/22/2026 12:51 AM, Dylan Hatch wrote:
> From: Weinan Liu <wnliu@xxxxxxxxxx>
>
> DWARF CFI (Call Frame Information) specifies how to recover the return
> address and callee-saved registers at each PC in a given function.
> Compilers are able to generate the CFI annotations when they compile
> the code to assembly language. For handcrafted assembly, we need to
> annotate them by hand.
>
> Annotate minimal CFI to enable stacktracing using SFrame for kernel
> exception entries through el1*_64_*() paths and irq entries through
> call_on_irq_stack()
>
> Signed-off-by: Weinan Liu <wnliu@xxxxxxxxxx>
> Signed-off-by: Dylan Hatch <dylanbhatch@xxxxxxxxxx>
> Suggested-by: Jens Remus <jremus@xxxxxxxxxxxxx>

Reviewed-by: Jens Remus <jremus@xxxxxxxxxxxxx>

> ---
> arch/arm64/kernel/entry.S | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
Regards,
Jens
--
Jens Remus
Linux on Z Development (D3303)
jremus@xxxxxxxxxx / jremus@xxxxxxxxxxxxx

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