Linus Torvalds writes: (Summary) On Thu, Feb 15, 2018 at 4:22 PM, Nadav Amit <nadav.amit@gmail.com> wrote:
Sure, I can see it working, but it's some really shady stuff, and now the scheduler needs to save/restore/check one more subtle bit. Get one thing wrong, and you'll blow all the PTI code out of the water.
you'll blow all the PTI code out of the water.
So now you tried to optimize one small case that most people won't use, but the downside is that you may make all our PTI work (and all the overhead for all the _normal_ cases) pointless.
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the work.Sure, I can see it working, but it's some really shady stuff, and now the scheduler needs to save/restore/check one more subtle bit. Get one thing wrong, and you'll blow all the PTI code out of the water.
you'll blow all the PTI code out of the water.
So now you tried to optimize one small case that most people won't use, but the downside is that you may make all our PTI work (and all the overhead for all the _normal_ cases) pointless.