Re: [PATCH 0/3] x86/mm: DEBUG_PAGEALLOC musings

Peter Zijlstra <[email protected]> Tue, 4 Aug 2026 22:01:34 +0200
Newsgroups org.kvack.linux-mm,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On Tue, Aug 04, 2026 at 11:34:36AM -0700, Dave Hansen wrote:
> On 7/29/26 04:08, Peter Zijlstra wrote:
> > my take on how we should be 'fixing' this DEBUG_PAGEALLOC thing. It appears to
> > boot in qemu with debug_pagealloc=on and such things.
> 
> The approach looks fine to me. The only thing we might want to do is add
> a warning of some kind in the split/join paths for CPA_DEBUG_PAGEALLOC.

So if you have lockdep enabled hitting them will scream bloody murder on
cpa_lock and pgd_lock.

But if you want I can sprinkle more explicit warns :-)