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Peter Zijlstra
a149180fbc
Note: needs to be in a section distinct from Retpolines such that the Retpoline RET substitution cannot possibly use immediate jumps. ORC unwinding for zen_untrain_ret() and __x86_return_thunk() is a little tricky but works due to the fact that zen_untrain_ret() doesn't have any stack ops and as such will emit a single ORC entry at the start (+0x3f). Meanwhile, unwinding an IP, including the __x86_return_thunk() one (+0x40) will search for the largest ORC entry smaller or equal to the IP, these will find the one ORC entry (+0x3f) and all works. [ Alexandre: SVM part. ] [ bp: Build fix, massages. ] Suggested-by: Andrew Cooper <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Borislav Petkov <[email protected]> Reviewed-by: Josh Poimboeuf <[email protected]> Signed-off-by: Borislav Petkov <[email protected]>