Re: [PATCH 2/9] mempool: add error injection support

[Christoph Hellwig <hch@lst.de>]

On Thu, Nov 06, 2025 at 07:29:00PM -0800, Eric Biggers wrote:
> > +static DECLARE_FAULT_ATTR(fail_mempool_alloc);
> > +
> > +static int __init mempool_faul_inject_init(void)
> > +{
> > +	return PTR_ERR_OR_ZERO(fault_create_debugfs_attr("fail_mempool_alloc",
> > +			NULL, &fail_mempool_alloc));
> > +}
> > +late_initcall(mempool_faul_inject_init);
> 
> Initcalls usually go at the bottom of the file.

For a generic init function yes.  But given that this is only for error
injection, I'd rather keep the error injection handling in one spot.

> 
> > +	if (should_fail_ex(&fail_mempool_alloc, 1, FAULT_NOWARN)) {
> 
> This doesn't build when CONFIG_FAULT_INJECTION=n.

Yeah, the buildbot already told me.  For some reason there is a
!CONFIG_FAULT_INJECTION stube for should_fail_ex, but the flags are
not defined in that case.  I'll add another patch to the series to
fix it.