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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 Josh suggested we change the scope of the discussion to objtool. So, I have updated the Title/Abstract as follows: Title: Toolchain support for objtool in the Linux kernel Abstract: The Linux kernel relies on objtool for performing a host of validations, metadata generation, and other fixups and annotations. One of Objtool's feature is stack metadata validation and generation which forms the backbone of kernel's reliable stack unwinding needs. In this session, we will discuss what components of the objtool, in general, can get some help from the toolchain. We will also discuss what assistance can be provided for the usecase of reliable stack tracing. For reliable stack traces, correct and complete metadata is only one of the pillars. We will discuss the additional components that are required. At LPC 2021, we talked about the proposal to define and generate CTF Frame unwind information in the GNU Toolchain. There was also a discussion on 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.