[BUG] ibm_emac: kernel panic with CONFIG_SLOB=y

[Eugene Surovegin]

On Tue, Aug 01, 2006 at 10:40:11PM +0200, Karol Lewandowski wrote:
> Hi,
> 
> I'm getting reproductible kernel panic when I use smaller SLOB
> allocator (instead of SLAB).  This is reproductible but very randomly
> -- sometimes it happens during bootup, sometimes few minutes later.
> 
> Hardware is custom board with IBM405EP (very close to Bubingna, just
> no RTC):
> 
> # cat /proc/cpuinfo
> processor	: 0
> cpu		: 405EP
> clock		: 200MHz
> revision	: 9.80 (pvr 5121 0950)
> bogomips	: 199.47
> machine		: MagicBox
> plb bus clock	: 100MHz
> pci bus clock	: 25MHz
> 
> Enabling SLAB instead of SLOB fixes this, so I assume this is driver
> issue.

This is probably the same issue  I had with SLAB debugging.

In short, those allocators aren't compatible with non-coherent cache 
archs (like 4xx), because driver assumes at least L1 cache line 
alignment for all allocated memory.

For more info, you can read this post:

http://ozlabs.org/pipermail/linuxppc-embedded/2006-February/022087.html

-- 
Eugene