Re: [Xen-devel] [PATCH v4 7/9] livepatch: NOP if func->new_[addr] is zero.

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 24.08.16 at 04:22, <konrad.wilk@xxxxxxxxxx> wrote:
> The NOP functionality will NOP any of the code at
> the 'old_addr' or at 'name' if the 'new_addr' is zero.
> The purpose of this is to NOP out calls, such as:
> 
>  e8 <4-bytes-offset>
> 
> (5 byte insn), or on ARM a 4 byte insn for branching.
> But on x86 we could NOP instructions that are much
> shorter or longer (up to 15 bytes).

And we could NOP multiple instructions in one go, i.e. the new
boundary you introduce is still arbitrary.

Jan


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