From 847ce401df392b0704369fd3f75df614ac1414b4 Mon Sep 17 00:00:00 2001 From: Wu Fengguang Date: Wed, 16 Dec 2009 12:19:58 +0100 Subject: HWPOISON: Add unpoisoning support The unpoisoning interface is useful for stress testing tools to reclaim poisoned pages (to prevent OOM) There is no hardware level unpoisioning, so this cannot be used for real memory errors, only for software injected errors. Note that it may leak pages silently - those who have been removed from LRU cache, but not isolated from page cache/swap cache at hwpoison time. Especially the stress test of dirty swap cache pages shall reboot system before exhausting memory. AK: Fix comments, add documentation, add printks, rename symbol Signed-off-by: Wu Fengguang Signed-off-by: Andi Kleen --- Documentation/vm/hwpoison.txt | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) (limited to 'Documentation/vm') diff --git a/Documentation/vm/hwpoison.txt b/Documentation/vm/hwpoison.txt index 3ffadf8da61f..f047e75acb23 100644 --- a/Documentation/vm/hwpoison.txt +++ b/Documentation/vm/hwpoison.txt @@ -98,10 +98,22 @@ madvise(MADV_POISON, ....) hwpoison-inject module through debugfs - /sys/debug/hwpoison/corrupt-pfn -Inject hwpoison fault at PFN echoed into this file +/sys/debug/hwpoison/ +corrupt-pfn + +Inject hwpoison fault at PFN echoed into this file. + +unpoison-pfn + +Software-unpoison page at PFN echoed into this file. This +way a page can be reused again. +This only works for Linux injected failures, not for real +memory failures. + +Note these injection interfaces are not stable and might change between +kernel versions Architecture specific MCE injector -- cgit v1.2.3