On Thu, Apr 16, 2020 at 06:48:44AM +0200, Florian Weimer wrote: > * Rich Felker: > > > My preference would be that it work just like the i386 AT_SYSINFO > > where you just replace "int $128" with "call *%%gs:16" and the kernel > > provides a stub in the vdso that performs either scv or the old > > mechanism with the same calling convention. > > The i386 mechanism has received some criticism because it provides an > effective means to redirect execution flow to anyone who can write to > the TCB. I am not sure if it makes sense to copy it.
Indeed that's a good point. Do you have ideas for making it equally efficient without use of a function pointer in the TCB? Rich
