Re: powerpc: Avoid panic during boot due to divide by zero in init_cache_info()
From: Michael Ellerman <hidden>
Date: 2017-03-08 07:25:58
On Sat, 2017-03-04 at 23:54:34 UTC, Anton Blanchard wrote:
From: Anton Blanchard <redacted>
I see a panic in early boot when building with a recent gcc toolchain.
The issue is a divide by zero, which is undefined. Older toolchains
let us get away with it:
int foo(int a) { return a / 0; }
foo:
li 9,0
divw 3,3,9
extsw 3,3
blr
But newer ones catch it:
foo:
trap
Add a check to avoid the divide by zero.
Fixes: bd067f83b084 ("powerpc/64: Fix naming of cache block vs. cache line")
Signed-off-by: Anton Blanchard <redacted>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>Applied to powerpc fixes, thanks. https://git.kernel.org/powerpc/c/6ba422c75facb1b1e0e206c464ee12 cheers