powerpc/lib: Fix the feature fixup tests to actually work
The code patching code has always been a bit confused about whether it's best to use void *, unsigned int *, char *, etc. to point to instructions. In fact in the feature fixups tests we use both unsigned int[] and u8[] in different places. Unfortunately the tests that use unsigned int[] calculate the size of the code blocks using subtraction of those unsigned int pointers, and then pass the result to memcmp(). This means we're only comparing 1/4 of the bytes we need to, because we need to multiply by sizeof(unsigned int) to get the number of *bytes*. The result is that the tests do all the patching and then only compare some of the resulting code, so patching bugs that only effect that last 3/4 of the code could slip through undetected. It turns out that hasn't been happening, although one test had a bad expected case (see previous commit). Fix it for now by multiplying the size by 4 in the affected functions. Fixes: 362e7701 ("powerpc: Add self-tests of the feature fixup code") Epic-brown-paper-bag-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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