Re: [RFC PATCH v1 7/9] x86: Add unsafe_copy_from_user()
Linus Torvalds <[email protected]>
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On Mon, 27 Apr 2026 at 12:19, Yury Norov <[email protected]> wrote: > > This is what Linus said when added x86 implementation for copy_from_user() > in c512c69187197: Note that some things have happily changed in the six+ years since... > That's partly because we have no current users of it, but also partly > because the copy_from_user() case is slightly different and cannot > efficiently be implemented in terms of a unsafe_get_user() loop (because > gcc can't do asm goto with outputs). now everybody can do asm goto with outputs. Yes, it's disabled on older versions, so it's not *always* available, but all modern versions do it. And if you care about performance, you won't be using an old compiler. Linus