Re: [PATCH] kasan: turn off asan-stack for clang-8 and earlier

From: Qian Cai
Date: Tue Feb 19 2019 - 20:25:28 EST




On 2/19/19 7:33 PM, Kostya Serebryany wrote:
>>> Well, I am using clang 8.0 on arm64 and running the kernel just fine for a few
>>> weeks now and never trigger a single stack overflow (THREAD_SHIFT = 15) because
>>> I never use any of those drivers you mentioned above. I don't think it is a good
>>> idea to blankly remove the testing coverage here and affect people don't use all
>>> those offensive functions at all.
>>
>> Thanks for the patch, Arnd! Hopefully we can fix that up in Clang
>> soon. Qian, I guess the alternative would be to add `-mllvm
>> -asan-stack=0` on potentially up to 140 Makefiles?

Depends on the exact stack consumption of those 140 functions. For example, I
don't care if you turn-off -asan-stack if the current stack size is < 32k.

For those functions always consume like a lot of stack like 8k or more, fix them
in Makefile if not too many of them.