Re: [PATCH] powerpc: Avoid panic during boot due to divide by zero in init_cache_info()
From: Michael Ellerman <mpe@ellerman.id.au>
Date: 2017-03-05 10:36:44
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Anton Blanchard [off-list ref] writes:
quoted hunk ↗ jump to hunk
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index adf2084..afd1c26 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c@@ -408,7 +408,8 @@ static void init_cache_info(struct ppc_cache_info *info, u32 size, u32 lsize, info->line_size = lsize; info->block_size = bsize; info->log_block_size = __ilog2(bsize); - info->blocks_per_page = PAGE_SIZE / bsize; + if (bsize) + info->blocks_per_page = PAGE_SIZE / bsize;
And we should probably initialise it to zero just in case, so I added:
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index afd1c2623459..9cfaa8b69b5f 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c@@ -410,6 +410,8 @@ static void init_cache_info(struct ppc_cache_info *info, u32 size, u32 lsize, info->log_block_size = __ilog2(bsize); if (bsize) info->blocks_per_page = PAGE_SIZE / bsize; + else + info->blocks_per_page = 0; if (sets == 0) info->assoc = 0xffff;
cheers