From 82f71ae4a2b829a25971bdf54b4d0d3d69d3c8b7 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Wed, 6 Aug 2014 16:06:36 -0700 Subject: [PATCH] mm: catch memory commitment underflow Print a warning (if CONFIG_DEBUG_VM=y) when memory commitment becomes too negative. This shouldn't happen any more - the previous two patches fixed the committed_as underflow issues. [akpm@linux-foundation.org: use VM_WARN_ONCE, per Dave] Signed-off-by: Konstantin Khlebnikov Cc: Hugh Dickins Cc: Dave Hansen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mmap.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/mm/mmap.c b/mm/mmap.c index 129b847d30cc..64c9d736155c 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -31,6 +31,7 @@ #include #include #include +#include #include #include #include @@ -134,6 +135,10 @@ int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin) { unsigned long free, allowed, reserve; + VM_WARN_ONCE(percpu_counter_read(&vm_committed_as) < + -(s64)vm_committed_as_batch * num_online_cpus(), + "memory commitment underflow"); + vm_acct_memory(pages); /* -- 2.20.1