From: Guohua Zhong
Sent: 24 August 2020 14:26
In generic version in lib/math/div64.c, there is no checking of 'base' either. Do we really want to add this check in the powerpc version only ?
The only user of __div64_32() is do_div() in include/asm-generic/div64.h. Wouldn't it be better to do the check there ?
Christophe
Yet, I have noticed that there is no checking of 'base' in these functions. But I am not sure how to check is better.As we know that the result is undefined when divisor is zero. It maybe good to print error and dump stack.
I thought that the onus was put on the caller to avoid divide by zero.
On x86 divide by zero causes an exception which (I'm pretty sure) leads to a oops/panic.
David
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