From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Date: Sun, 06 Oct 2019 08:56:42 +0000 Subject: [PATCH v6 06/10] mm/memory_hotplug: Poison memmap in remove_pfn_range_from_zone() Message-Id: <20191006085646.5768-7-david@redhat.com> List-Id: References: <20191006085646.5768-1-david@redhat.com> In-Reply-To: <20191006085646.5768-1-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org Cc: linux-s390@vger.kernel.org, Michal Hocko , linux-ia64@vger.kernel.org, Pavel Tatashin , linux-sh@vger.kernel.org, x86@kernel.org, David Hildenbrand , linux-mm@kvack.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, Dan Williams , linux-arm-kernel@lists.infradead.org, Oscar Salvador Let's poison the pages similar to when adding new memory in sparse_add_section(). Also call remove_pfn_range_from_zone() from memunmap_pages(), so we can poison the memmap from there as well. While at it, calculate the pfn in memunmap_pages() only once. Cc: Andrew Morton Cc: David Hildenbrand Cc: Oscar Salvador Cc: Michal Hocko Cc: Pavel Tatashin Cc: Dan Williams Signed-off-by: David Hildenbrand --- mm/memory_hotplug.c | 3 +++ mm/memremap.c | 2 ++ 2 files changed, 5 insertions(+) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 5b003ffa5dc9..bf5173e7913d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -464,6 +464,9 @@ void __ref remove_pfn_range_from_zone(struct zone *zone, struct pglist_data *pgdat = zone->zone_pgdat; unsigned long flags; + /* Poison struct pages because they are now uninitialized again. */ + page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * nr_pages); + #ifdef CONFIG_ZONE_DEVICE /* * Zone shrinking code cannot properly deal with ZONE_DEVICE. So diff --git a/mm/memremap.c b/mm/memremap.c index 70263e6f093e..7fed8bd32a18 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -139,6 +139,8 @@ void memunmap_pages(struct dev_pagemap *pgmap) nid = page_to_nid(first_page); mem_hotplug_begin(); + remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(res->start), + PHYS_PFN(resource_size(res))); if (pgmap->type = MEMORY_DEVICE_PRIVATE) { __remove_pages(PHYS_PFN(res->start), PHYS_PFN(resource_size(res)), NULL); -- 2.21.0