Re: [PATCH v7 0/6] arm64: support FEAT_BBM level 2 and large block mapping when rodata=full

[Yang Shi <yang@os.amperecomputing.com>]

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> 3. kprobe. S390's alloc_insn_page() does call set_memory_rox(), x86 
> also called set_memory_rox() before switching to execmem cache. The 
> execmem cache calls set_memory_rox(). I don't know why ARM64 doesn't 
> call it.

When I'm trying to find out the proper fix tag for this, I happened to 
figure out why ARM64 doesn't call it. ARM64 actually called 
set_memory_ro() before commit 10d5e97c1bf8 ("arm64: use PAGE_KERNEL_ROX 
directly in alloc_insn_page"). But this commit removed it. It seems like 
the author and reviewers overlooked set_memory_ro() also changes direct 
map permission. So I believe adding set_memory_rox() is the right fix.

Thanks,
Yang

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> So I think we just need to fix #1 and #3 per the above analysis. If 
> this analysis look correct to you guys, I will prepare two patches to 
> fix them.
>
> Thanks,
> Yang
>
>>
>>
>>> Thanks,
>>> Ryan
>>>
>>>> Thanks,
>>>> Yang
>>>>
>>>>> Thanks,
>>>>> Yang
>>>>>
>>>>>> Thanks,
>>>>>> Ryan
>>>>>>
>>>>>>
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