+arm64 people...
On Mon, Mar 28, 2022 at 10:14:38PM +0200, Peter Zijlstra wrote: > On Mon, Mar 28, 2022 at 12:59:20PM -0700, Josh Poimboeuf wrote: > > > I'm not making any major changes to the code, just shuffling things > > around to make the interface more modular. I hope to have something > > soon (this week). Peter recently added a big feature (Intel IBT) which > > is already in -next. > > Hit Linus' tree yesterday :-) > > > Some years ago Kamalesh Babulal had a prototype of objtool for ppc64le > > which did the full stack validation. I'm not sure what ever became of > > that. > > I've also heard chatter about s390. > > > FWIW, there have been some objtool patches for arm64 stack validation, > > but the arm64 maintainers have been hesitant to get on board with > > objtool, as it brings a certain maintenance burden. Especially for the > > full stack validation and ORC unwinder. But if you only want inline > > static calls and/or mcount then it'd probably be much easier to > > maintain. > > IIRC the major stumbling block for arm64 is the whole jump-table thing. > Either they need to rely on compiler plugins to provide objtool that > data (yuck, since we support at least 2 different compilers), disable > jump-tables (yuck, for that limits code-gen just to please a tool) or > use DWARF (yuck, because build times). > > There was a little talk about an impromptu 'abi' to communicate > jump-table details to objtool without going full on DWARF, but that > seems to have hit a dead end again.