[PATCH] oom: Mitigate suer-user's bonus of oom-score

[KOSAKI Motohiro]

Currently, badness calculation code of oom contemplate following bonus.
 - Super-user have quartering oom-score
 - CAP_SYS_RAWIO process (e.g. database) also have quartering oom-score

The problem is, Super-users have CAP_SYS_RAWIO too. Then, they have
sixteenthing bonus. it's obviously too excessive and meaningless.

This patch fixes it.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx>
---
 mm/oom_kill.c |   13 +++++--------
 1 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index ea2147d..40d323d 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -152,18 +152,15 @@ unsigned long badness(struct task_struct *p, unsigned long uptime)
 	/*
 	 * Superuser processes are usually more important, so we make it
 	 * less likely that we kill those.
-	 */
-	if (has_capability_noaudit(p, CAP_SYS_ADMIN) ||
-	    has_capability_noaudit(p, CAP_SYS_RESOURCE))
-		points /= 4;
-
-	/*
-	 * We don't want to kill a process with direct hardware access.
+	 *
+	 * Plus, We don't want to kill a process with direct hardware access.
 	 * Not only could that mess up the hardware, but usually users
 	 * tend to only have this flag set on applications they think
 	 * of as important.
 	 */
-	if (has_capability_noaudit(p, CAP_SYS_RAWIO))
+	if (has_capability_noaudit(p, CAP_SYS_ADMIN) ||
+	    has_capability_noaudit(p, CAP_SYS_RESOURCE) ||
+	    has_capability_noaudit(p, CAP_SYS_RAWIO))
 		points /= 4;
 
 	/*
-- 
1.6.2.5




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