Re: [PATCH bpf-next 1/3] riscv: stacktrace: Implement arch_bpf_stack_walk() for BPF

[Varun R Mallya <varunrmallya@gmail.com>]

On Sun, Jun 21, 2026 at 02:56:58PM +0000, sashiko-bot@kernel.org wrote:
> [Severity: High]
> Does this code need to resolve the ftrace trampoline address?
Yes. I forgot to add that in there. 
> Looking at the generic unwinder walk_stackframe() in the same file, it uses
> ftrace_graph_ret_addr() to recover the real instruction pointer when the
> ftrace function graph tracer is active.
> 
> If a kernel function in the unwinding chain is traced by ftrace, frame->ra
> will point to return_to_handler on the stack. Because return_to_handler is a
> core kernel text address rather than a BPF program address, the stack walker
> might silently skip the caller's frame and miss the BPF exception boundary.
> This would leave the context uninitialized and trigger a kernel panic in
> bpf_throw() when it validates the missing boundary.
> 
> Could pc be passed through ftrace_graph_ret_addr() here to ensure the real
> return address is consumed?
Addressing in next version.
-Varun
> > +	}
> > +}
> 
> -- 
> Sashiko AI review · https://sashiko.dev/#/patchset/20260621144259.288135-1-varunrmallya@gmail.com?part=1