Messages in this thread | | | Date | Wed, 20 Nov 2013 13:00:11 -0800 | From | "H. Peter Anvin" <> | Subject | Re: [PATCH] Add a text_poke syscall |
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On 11/20/2013 09:25 AM, Andi Kleen wrote: > "H. Peter Anvin" <hpa@zytor.com> writes: >> >> We're talking user space here, which has different requirement (COW, >> memory protection, ...) which means it is not really the same code. You >> can't take a page fault while patching the kernel. > > The syscall pins the page, then it calls the kernel code. > There are no page faults during patching. >
But you don't need to pin anything if you just do it in userspace. Again, it is particularly poignant for large batched operations.
-hpa
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