lkml.org 
[lkml]   [2020]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v7 11/14] mm,hwpoison: return 0 if the page is already poisoned in soft-offline
Date
Currently, there is an inconsistency when calling soft-offline from
different paths on a page that is already poisoned.

1) madvise:

madvise_inject_error skips any poisoned page and continues
the loop.
If that was the only page to madvise, it returns 0.

2) /sys/devices/system/memory/:

When calling soft_offline_page_store()->soft_offline_page(),
we return -EBUSY in case the page is already poisoned.
This is inconsistent with a) the above example and b)
memory_failure, where we return 0 if the page was poisoned.

Fix this by dropping the PageHWPoison() check in madvise_inject_error, and
let soft_offline_page return 0 if it finds the page already poisoned.

Please, note that this represents a user-api change, since now the return
error when calling soft_offline_page_store()->soft_offline_page() will be
different.

Signed-off-by: Oscar Salvador <osalvador@suse.de>
---
mm/madvise.c | 5 -----
mm/memory-failure.c | 4 ++--
2 files changed, 2 insertions(+), 7 deletions(-)

diff --git a/mm/madvise.c b/mm/madvise.c
index f3a86d547ceb..5ab978b828f0 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -896,11 +896,6 @@ static int madvise_inject_error(int behavior,
*/
size = page_size(compound_head(page));

- if (PageHWPoison(page)) {
- put_page(page);
- continue;
- }
-
if (behavior == MADV_SOFT_OFFLINE) {
pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n",
pfn, start);
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 7c122cca9f31..087f070b06b5 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -1802,7 +1802,7 @@ static int __soft_offline_page(struct page *page)
unlock_page(page);
put_page(page);
pr_info("soft offline: %#lx page already poisoned\n", pfn);
- return -EBUSY;
+ return 0;
}

if (!PageHuge(page))
@@ -1906,7 +1906,7 @@ int soft_offline_page(unsigned long pfn, int flags)
pr_info("soft offline: %#lx page already poisoned\n", pfn);
if (flags & MF_COUNT_INCREASED)
put_page(page);
- return -EBUSY;
+ return 0;
}

get_online_mems();
--
2.26.2
\
 
 \ /
  Last update: 2020-09-22 15:57    [W:0.166 / U:0.700 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site