Commit 5b57b8f2 authored Jan 30, 2020 by Vlastimil Babka Committed by Linus Torvalds Jan 31, 2020

mm/debug.c: always print flags in dump_page()

Commit 76a1850e ("mm/debug.c: __dump_page() prints an extra line")
inadvertently removed printing of page flags for pages that are neither
anon nor ksm nor have a mapping.  Fix that.

Using pr_cont() again would be a solution, but the commit explicitly
removed its use.  Avoiding the danger of mixing up split lines from
multiple CPUs might be beneficial for near-panic dumps like this, so fix
this without reintroducing pr_cont().

Link: http://lkml.kernel.org/r/9f884d5c-ca60-dc7b-219c-c081c755fab6@suse.cz


Fixes: 76a1850e ("mm/debug.c: __dump_page() prints an extra line")
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reported-by: Michal Hocko <mhocko@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 8c96f1bc

mm/debug.c

+5 −3

Original line number	Diff line number	Diff line
		@@ -47,6 +47,7 @@ void __dump_page(struct page page, const char reason)
		struct address_space *mapping;
		bool page_poisoned = PagePoisoned(page);
		int mapcount;
		char *type = "";

		/*
		* If struct page is poisoned don't access Page*() functions as that
		@@ -78,9 +79,9 @@ void __dump_page(struct page page, const char reason)
		page, page_ref_count(page), mapcount,
		page->mapping, page_to_pgoff(page));
		if (PageKsm(page))
		pr_warn("ksm flags: %#lx(%pGp)\n", page->flags, &page->flags);
		type = "ksm ";
		else if (PageAnon(page))
		pr_warn("anon flags: %#lx(%pGp)\n", page->flags, &page->flags);
		type = "anon ";
		else if (mapping) {
		if (mapping->host && mapping->host->i_dentry.first) {
		struct dentry *dentry;
		@@ -88,10 +89,11 @@ void __dump_page(struct page page, const char reason)
		pr_warn("%ps name:\"%pd\"\n", mapping->a_ops, dentry);
		} else
		pr_warn("%ps\n", mapping->a_ops);
		pr_warn("flags: %#lx(%pGp)\n", page->flags, &page->flags);
		}
		BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1);

		pr_warn("%sflags: %#lx(%pGp)\n", type, page->flags, &page->flags);

		hex_only:
		print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32,
		sizeof(unsigned long), page,

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