Re: [PATCH] mm/memory-failure: fix deadlock when hugetlb_optimize_vmemmap is enabled

From: Oscar Salvador
Date: Tue Apr 09 2024 - 10:10:45 EST


On Sun, Apr 07, 2024 at 04:54:56PM +0800, Miaohe Lin wrote:
> In short, below scene breaks the lock dependency chain:
>
> memory_failure
> __page_handle_poison
> zone_pcp_disable -- lock(pcp_batch_high_lock)
> dissolve_free_huge_page
> __hugetlb_vmemmap_restore_folio
> static_key_slow_dec
> cpus_read_lock -- rlock(cpu_hotplug_lock)
>
> Fix this by calling drain_all_pages() instead.
>
> Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>

Acked-by: Oscar Salvador <osalvador@xxxxxxx>

Thanks!


--
Oscar Salvador
SUSE Labs