path: root/lib/bug.c
diff options
authorRusty Russell <rusty@rustcorp.com.au>2013-01-12 13:27:34 +1030
committerRusty Russell <rusty@rustcorp.com.au>2013-01-12 13:27:46 +1030
commit1fb9341ac34825aa40354e74d9a2c69df7d2c304 (patch)
treeebb2b836673d722845cd0a17c836799d800ae810 /lib/bug.c
parent0d21b0e3477395e7ff2acc269f15df6e6a8d356d (diff)
module: put modules in list much earlier.
Prarit's excellent bug report: > In recent Fedora releases (F17 & F18) some users have reported seeing > messages similar to > > [ 15.478160] kvm: Could not allocate 304 bytes percpu data > [ 15.478174] PERCPU: allocation failed, size=304 align=32, alloc from > reserved chunk failed > > during system boot. In some cases, users have also reported seeing this > message along with a failed load of other modules. > > What is happening is systemd is loading an instance of the kvm module for > each cpu found (see commit e9bda3b). When the module load occurs the kernel > currently allocates the modules percpu data area prior to checking to see > if the module is already loaded or is in the process of being loaded. If > the module is already loaded, or finishes load, the module loading code > releases the current instance's module's percpu data. Now we have a new state MODULE_STATE_UNFORMED, we can insert the module into the list (and thus guarantee its uniqueness) before we allocate the per-cpu region. Reported-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Tested-by: Prarit Bhargava <prarit@redhat.com>
Diffstat (limited to 'lib/bug.c')
1 files changed, 1 insertions, 0 deletions
diff --git a/lib/bug.c b/lib/bug.c
index a28c1415357c..d0cdf14c651a 100644
--- a/lib/bug.c
+++ b/lib/bug.c
@@ -55,6 +55,7 @@ static inline unsigned long bug_addr(const struct bug_entry *bug)
+/* Updates are protected by module mutex */
static LIST_HEAD(module_bug_list);
static const struct bug_entry *module_find_bug(unsigned long bugaddr)