Re: [PATCH] kprobes: bad manipulation of 2 byte opcode on x86_64

From: Satoshi Oshima
Date: Fri May 19 2006 - 10:20:24 EST

Andi Kleen wrote:
> On Friday 19 May 2006 10:29, Richard J Moore wrote:
>> Is there any possibility of a inducing a page fault when checking the
>> second byte?
> AFAIK instr is in the out of line instruction copy. Kernel would need
> to be pretty broken already if that page faulted.

There is no possibility that copied instruction step over
a page boundary. Instruction slot is in the page that
is allocated in get_insn_slot(). And get_insn_slot()
acquires the page by module_alloc(), and divides into

Satoshi Oshima
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