Re: iov_kunit_copy_to_kvec: ASSERTION FAILED at lib/tests/kunit_iov_iter.c:63, Expected got == npages, but, got == 1 (0x1), npages == 256 (0x100) (v7.0.2, ppc)

[Erhard Furtner <erhard_f@mailbox.org>]

> This happens in alloc_pages_bulk_noprof(), due to
> 
> 	pcp = pcp_spin_trylock(zone->per_cpu_pageset);
> 	if (!pcp)
> 		goto failed;
> 
> Because:
> 
> #ifdef CONFIG_SMP
> [...]
> /*
>    * On CONFIG_SMP=n the UP implementation of spin_trylock() never fails
> and thus
>    * is not compatible with our locking scheme. However we do not need
> pcp for
>    * scalability in the first place, so just make all the trylocks fail
> and take
>    * the slow path unconditionally.
>    */
> #else
> #define pcp_spin_trylock(ptr)		\
> 		NULL
> 
> 
> So apparently it is expected that alloc_pages_bulk() returns 1 on non-SMP.
> 
> Christophe

I got SMP set as my G4 DP got 2 x 7450 cpus.

I can attach full kernel .config when I return on Saturday.

Regards,
Erhard