static unsigned long __init get_loops_per_jiffy(void)
{
        unsigned long lpj = tsc_khz * KHZ;

        do_div(lpj, HZ);
        return lpj;
}
Just tried this with 4.19-rc2 on x86(32bit). lpj return as zero which is not 
expected
After disassembling the code,
        0xc1239a9e <+199>:   imul   $0x3e8,0xc12296e4,%edx
        0xc1239aa8 <+209>:   xor    %ecx,%ecx
        0xc1239aaa <+211>:   test   %edx,%edx
        0xc1239aac <+213>:   mov    %eax,%ebx
        0xc1239aae <+215>:   je     0xc1239abd <tsc_init+230>
        0xc1239ab0 <+217>:   mov    $0x64,%ecx
        0xc1239ab5 <+222>:   mov    %edx,%eax
        0xc1239ab7 <+224>:   xor    %edx,%edx
        0xc1239ab9 <+226>:   div    %ecx
        0xc1239abb <+228>:   mov    %eax,%ecx
        0xc1239abd <+230>:   mov    %ebx,%eax
        0xc1239abf <+232>:   mov    $0x64,%ebx
        0xc1239ac4 <+237>:   div    %ebx
        0xc1239ac6 <+239>:   mov    %ecx,%edx
imul will load the result into %edx, %edx supposed to be high 32 bit which is 
not zero,
It should be zero in this case. both lpj and tsc_khz should be u64 to work 
properly.

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