Hi everyone, This patch set makes the following 2 changes:
- It adds an exception opcode detector to prevent kprobing on INTs and UDs. These opcodes serves special purposes in the kernel and kprobing them will also cause the stack trace to be polluted by the copy buffer address. This is suggested by Masami. - At the same time, this patch set also boosts more opcodes from the group 2/3/4/5. The newly boosted opcodes are all arithmetic instructions with semantics that are easy to reason about, and therefore, they are able to be boosted and executed out-of-line. These instructions were not boosted previously because they use opcode extensions that are not handled by the kernel. But now with the instruction decoder they can be easily handled. Boosting (and further jump optimizing) these instructions leads to a 10x performance gain for a single probe on QEMU. Jinghao Jia (2): x86/kprobes: Prohibit kprobing on INT and UD x86/kprobes: boost more instructions from grp2/3/4/5 arch/x86/kernel/kprobes/core.c | 54 ++++++++++++++++++++++++++-------- 1 file changed, 41 insertions(+), 13 deletions(-) -- 2.43.0
