Discussion on toolchain support for reliable stacktracing at LPC 2022

[Indu Bhagat <indu.bhagat@oracle.com>]

Hello,

What do you think about the following activity at the LPC Plumbers 2022 
@ Toolchains and Kernel track ?

Title:
Toolchain support for reliable stack tracing in the Linux kernel

Abstract:
The Linux kernel uses a two fold approach for its stack unwinding needs
  -- ORC: the kernel's stack unwinding format
  -- objtool: a tool to generate the unwind information by 
post-processing the generated binaries

For reliable stack traces, correct and complete metadata is only one of 
the pillars. The purpose of this discussion is to brainstorm the 
additional components  that are required in the form of toolchain 
support for assisting the kernel's requirement of reliable stack traces.

Earlier at LPC 2021, we talked about the proposal to define and generate 
CTF Frame unwind information in the GNU Toolchain, and also in another 
session, the issues with objtool on arm64. In this session, we plan to 
converge these discussions with a perspective of what toolchain support 
can be provided to support objtool in the Linux kernel to begin with.

Participants: Indu Bhagat, Josh Poimboeuf, anyone else ?

I am looking at the material Mark sent (in another thread) and the 
pointers in objtool session slides (from LPC 2021) meanwhile. If you 
have suggestions to refine the abstract with more detailed content, that 
will be welcome too.

Thanks
Indu