linux-kernel - [PATCH] mm: memory_hotplug: put migration failure information under DEBUG

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1606140196-6053-1-git-send-email-charante@codeaurora.org>
Date:   Mon, 23 Nov 2020 19:33:16 +0530
From:   Charan Teja Reddy <charante@...eaurora.org>
To:     akpm@...ux-foundation.org, david@...hat.com, mhocko@...e.com,
        linux-mm@...ck.org
Cc:     linux-kernel@...r.kernel.org,
        Charan Teja Reddy <charante@...eaurora.org>
Subject: [PATCH] mm: memory_hotplug: put migration failure information under DEBUG_VM

When the pages are failed to get isolate or migrate, the page owner
information along with page info is dumped. If there are continuous
failures in migration(say page is pinned) or isolation, the log buffer
is simply getting flooded with the page owner information. As most of
the times page info is sufficient to know the causes for failures of
migration or isolation, place the page owner information under DEBUG_VM.

Signed-off-by: Charan Teja Reddy <charante@...eaurora.org>
---
 mm/memory_hotplug.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 63b2e46..f48f30d 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1326,7 +1326,10 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 
 		} else {
 			pr_warn("failed to isolate pfn %lx\n", pfn);
-			dump_page(page, "isolation failed");
+			__dump_page(page, "isolation failed");
+#if defined(CONFIG_DEBUG_VM)
+			dump_page_owner(page);
+#endif
 		}
 		put_page(page);
 	}
@@ -1357,7 +1360,10 @@ do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 			list_for_each_entry(page, &source, lru) {
 				pr_warn("migrating pfn %lx failed ret:%d ",
 				       page_to_pfn(page), ret);
-				dump_page(page, "migration failure");
+				__dump_page(page, "migration failure");
+#if defined(CONFIG_DEBUG_VM)
+				dump_page_owner(page);
+#endif
 			}
 			putback_movable_pages(&source);
 		}
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a
member of the Code Aurora Forum, hosted by The Linux Foundation