Messages in this thread | | | From | Andy Lutomirski <> | Date | Fri, 26 Jan 2018 11:02:54 -0800 | Subject | Re: [PATCH] x86/retpoline/entry: Disable the entire SYSCALL64 fast path with retpolines on |
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On Fri, Jan 26, 2018 at 10:54 AM, Linus Torvalds <torvalds@linux-foundation.org> wrote: > On Fri, Jan 26, 2018 at 10:23 AM, Andy Lutomirski <luto@kernel.org> wrote: >> >> The issue is that doing it this way gives us, effectively: >> >> long sys_foo(int a, int b) >> { >> body here; >> } >> >> long SyS_foo(const struct pt_regs *regs) >> { >> return sys_foo(regs->di, regs->si); >> } >> >> whereas what we want is *static* long sys_foo(...). > > How about just marking 'sys_foo()' as being always_inline (but still > not static)? Because the case that _matters_ is that SyS_foo(), thing > when this is enabled. > > Sure, you'll get two copies of the code (one in SyS_foo(), the other > being the callable-from C 'sys_foo()' that is exported and almost > never used). But that seems a fairly small price to pay. We could > leave it for later to try to get rid of the unused copies entirely. >
I could do that, but Josh Triplett will yell at me.
Anyway, I'll fiddle with it. This isn't exactly high priority.
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