Re: mm/percpu.c: use smarter memory allocation for struct pcpu_alloc_info (crisv32 hang)

From: Tejun Heo
Date: Mon Nov 27 2017 - 15:54:29 EST


Hello, Nicolas.

On Mon, Nov 27, 2017 at 03:51:04PM -0500, Nicolas Pitre wrote:
> Subject: percpu: hack to let the CRIS architecture to boot until they clean up
>
> Commit 438a506180 ("percpu: don't forget to free the temporary struct
> pcpu_alloc_info") uncovered a problem on the CRIS architecture where
> the bootmem allocator is initialized with virtual addresses. Given it
> has:
>
> #define __va(x) ((void *)((unsigned long)(x) | 0x80000000))
>
> then things just work out because the end result is the same whether you
> give this a physical or a virtual address.
>
> Untill you call memblock_free_early(__pa(address)) that is, because
> values from __pa() don't match with the virtual addresses stuffed in the
> bootmem allocator anymore.
>
> Avoid freeing the temporary pcpu_alloc_info memory on that architecture
> until they fix things up to let the kernel boot like it did before.
>
> Signed-off-by: Nicolas Pitre <nico@xxxxxxxxxx>

This totally works for me. Replaced the revert with this one.

Thanks!

--
tejun