Re: [PATCH 1/2] mm/memory-failure: add panic_on_unrecoverable_memory_failure sysctl

[Breno Leitao <leitao@debian.org>]

On Mon, Mar 30, 2026 at 03:55:00PM +0800, Miaohe Lin wrote:
> On 2026/3/23 23:29, Breno Leitao wrote:
>
> > @@ -1298,6 +1309,10 @@ static int action_result(unsigned long pfn, enum mf_action_page_type type,
> >  	pr_err("%#lx: recovery action for %s: %s\n",
> >  		pfn, action_page_types[type], action_name[result]);
> >  
> > +	if (sysctl_panic_on_unrecoverable_mf &&
> > +	    type == MF_MSG_GET_HWPOISON && result == MF_IGNORED)
> > +		panic("Memory failure: %#lx: unrecoverable page", pfn);
> 
> MF_MSG_GET_HWPOISON contains some other scenarios. For example, an isolated folio will
> make get_hwpoison_page return -EIO so we will see MF_MSG_GET_HWPOISON and MF_IGNORED in
> action_result. But that's recoverable if folio is used by userspace thus panic will be
> unacceptable.
> Will it better to check type against MF_MSG_KERNEL_HIGH_ORDER?

Yes, I was discussing this with akpm, and maybe the better
approach would be to panic for types MF_MSG_KERNEL_HIGH_ORDER and MF_MSG_KERNEL.

In both cases, it seems that, the page would not be able to migrate. What do
you think about a change like this:


@@ -1298,6 +1309,10 @@ static int action_result(unsigned long pfn, enum mf_action_page_type type,
        pr_err("%#lx: recovery action for %s: %s\n",
                pfn, action_page_types[type], action_name[result]);

+       if (sysctl_panic_on_unrecoverable_mf && result == MF_IGNORED &&
+           (type == MF_MSG_KERNEL || type == MF_MSG_KERNEL_HIGH_ORDER))
+               panic("Memory failure: %#lx: unrecoverable page", pfn);
+
        return (result == MF_RECOVERED || result == MF_DELAYED) ? 0 : -EBUSY;
 }