Messages in this thread | | | Date | Fri, 25 Feb 2022 13:24:58 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH v2 16/39] x86/bpf: Add ENDBR instructions to prologue and trampoline |
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On Thu, Feb 24, 2022 at 03:37:31PM -0800, Josh Poimboeuf wrote:
> > @@ -2028,10 +2052,11 @@ int arch_prepare_bpf_trampoline(struct b > > /* skip patched call instruction and point orig_call to actual > > * body of the kernel function. > > */ > > - orig_call += X86_PATCH_SIZE; > > + orig_call += X86_PATCH_SIZE + 4*HAS_KERNEL_IBT; > > All the "4*HAS_KERNEL_IBT" everywhere is cute, but you might as well > just have IBT_ENDBR_SIZE (here and in other patches).
So there's two forms of this, only one has the 4 included:
(x * (1 + HAS_KERNEL_IBT)) (x + 4*HAS_KERNEL_IBT)
If I include the 4, then the first form would become something like:
(x * (1 + !!IBT_ENDBR_SIZE))
that ok?
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