On 09/08/2017 02:35 PM, Rakesh Pandit wrote:
If target type module e.g. pblk here is unloaded (rmmod) while module
is in use (after creating target) system crashes. We fix this by
using module API refcnt.
Signed-off-by: Rakesh Pandit <rakesh@xxxxxxxxxx>
---
drivers/lightnvm/core.c | 4 ++++
drivers/lightnvm/pblk-init.c | 1 +
include/linux/lightnvm.h | 1 +
3 files changed, 6 insertions(+)
diff --git a/drivers/lightnvm/core.c b/drivers/lightnvm/core.c
index bbea2c8..c39f87d 100644
--- a/drivers/lightnvm/core.c
+++ b/drivers/lightnvm/core.c
@@ -22,6 +22,7 @@
#include <linux/types.h>
#include <linux/sem.h>
#include <linux/bitmap.h>
+#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/miscdevice.h>
#include <linux/lightnvm.h>
@@ -316,6 +317,8 @@ static int nvm_create_tgt(struct nvm_dev *dev, struct nvm_ioctl_create *create)
list_add_tail(&t->list, &dev->targets);
mutex_unlock(&dev->mlock);
+ __module_get(tt->owner);
+
return 0;
err_sysfs:
if (tt->exit)
@@ -351,6 +354,7 @@ static void __nvm_remove_target(struct nvm_target *t)
nvm_remove_tgt_dev(t->dev, 1);
put_disk(tdisk);
+ module_put(t->type->owner);
list_del(&t->list);
kfree(t);
diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
index 5fe926b..77d6120 100644
--- a/drivers/lightnvm/pblk-init.c
+++ b/drivers/lightnvm/pblk-init.c
@@ -1059,6 +1059,7 @@ static struct nvm_tgt_type tt_pblk = {
.sysfs_init = pblk_sysfs_init,
.sysfs_exit = pblk_sysfs_exit,
+ .owner = THIS_MODULE,
};
static int __init pblk_module_init(void)
diff --git a/include/linux/lightnvm.h b/include/linux/lightnvm.h
index 81b71c6d..78a22e0 100644
--- a/include/linux/lightnvm.h
+++ b/include/linux/lightnvm.h
@@ -461,6 +461,7 @@ struct nvm_tgt_type {
/* For internal use */
struct list_head list;
+ struct module *owner;
};
extern struct nvm_tgt_type *nvm_find_target_type(const char *, int);
Thanks Rakesh. I've picked it up for 4.15.
