From 99f5b2bda28d5e91dc10a1c17043ae0074fae81f Mon Sep 17 00:00:00 2001
From: Naveen Ramaraj <nramaraj@codeaurora.org>
Date: Thu, 19 Mar 2015 12:48:55 -0700
Subject: [PATCH] smd_pkt: Add sanity check to avoid unregistering the driver
twice
Attempting to unregister it again will cause a panic
Bug: 18759663
Change-Id: Iff2adbc79136c55141f35b872cb70584d303a689
Signed-off-by: Naveen Ramaraj <nramaraj@codeaurora.org>
---
arch/arm/mach-msm/smd_pkt.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-msm/smd_pkt.c b/arch/arm/mach-msm/smd_pkt.c
index 9da145aec375..68aa66d997d8 100644
--- a/arch/arm/mach-msm/smd_pkt.c
+++ b/arch/arm/mach-msm/smd_pkt.c
@@ -49,12 +49,14 @@
#define DEVICE_NAME "smdpkt"
#define WAKELOCK_TIMEOUT (2*HZ)
+#define SMD_PKT_MAGIC (0xDEADBAAD)
struct smd_pkt_dev {
struct cdev cdev;
struct device *devicep;
void *pil;
char pdriver_name[PDRIVER_NAME_MAX_SIZE];
+ int magic;
struct platform_driver driver;
struct smd_channel *ch;
@@ -976,8 +978,14 @@ int smd_pkt_release(struct inode *inode, struct file *file)
smd_pkt_devp->ch = 0;
smd_pkt_devp->blocking_write = 0;
smd_pkt_devp->poll_mode = 0;
- platform_driver_unregister(&smd_pkt_devp->driver);
- smd_pkt_devp->driver.probe = NULL;
+ if (smd_pkt_devp->driver.probe) {
+ platform_driver_unregister(&smd_pkt_devp->driver);
+ smd_pkt_devp->driver.probe = NULL;
+ } else {
+ pr_err("%s: invalid unregister dev id:%d magic %x\n",
+ __func__, smd_pkt_devp->i,
+ smd_pkt_devp->magic);
+ }
if (smd_pkt_devp->pil)
pil_put(smd_pkt_devp->pil);
smd_pkt_devp->has_reset = 0;
@@ -1044,6 +1052,7 @@ static int __init smd_pkt_init(void)
smd_pkt_devp[i]->is_open = 0;
smd_pkt_devp[i]->poll_mode = 0;
smd_pkt_devp[i]->wakelock_locked = 0;
+ smd_pkt_devp[i]->magic = SMD_PKT_MAGIC;
init_waitqueue_head(&smd_pkt_devp[i]->ch_opened_wait_queue);
spin_lock_init(&smd_pkt_devp[i]->pa_spinlock);
@@ -1117,6 +1126,7 @@ static void __exit smd_pkt_cleanup(void)
for (i = 0; i < NUM_SMD_PKT_PORTS; ++i) {
cdev_del(&smd_pkt_devp[i]->cdev);
+ smd_pkt_devp[i]->magic = 0;
kfree(smd_pkt_devp[i]);
device_destroy(smd_pkt_classp,
MKDEV(MAJOR(smd_pkt_number), i));
--
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