tpm_tis: fix tis_lock with respect to RCU

cleanup_tis() -> tpm_remove_hardware() -> syncrhonize_rcu() is being
called in an atomic context (tis_lock spinlock held), which is not
allowed. Convert tis_lock to mutex.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Acked-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>

diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index a1748621111be511a8694a4d91ab74094f45c631..70fac9abb0e2b57e16857f00beb52ecd7c633f3f 100644 (file)
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -76,7 +76,7 @@ enum tis_defaults {
 #define        TPM_RID(l)                      (0x0F04 | ((l) << 12))
 
 static LIST_HEAD(tis_chips);
-static DEFINE_SPINLOCK(tis_lock);
+static DEFINE_MUTEX(tis_lock);
 
 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
 static int is_itpm(struct pnp_dev *dev)
@@ -689,9 +689,9 @@ static int tpm_tis_init(struct device *dev, resource_size_t start,
        }
 
        INIT_LIST_HEAD(&chip->vendor.list);
-       spin_lock(&tis_lock);
+       mutex_lock(&tis_lock);
        list_add(&chip->vendor.list, &tis_chips);
-       spin_unlock(&tis_lock);
+       mutex_unlock(&tis_lock);
 
 
        return 0;
@@ -855,7 +855,7 @@ static void __exit cleanup_tis(void)
 {
        struct tpm_vendor_specific *i, *j;
        struct tpm_chip *chip;
-       spin_lock(&tis_lock);
+       mutex_lock(&tis_lock);
        list_for_each_entry_safe(i, j, &tis_chips, list) {
                chip = to_tpm_chip(i);
                tpm_remove_hardware(chip->dev);
@@ -871,7 +871,7 @@ static void __exit cleanup_tis(void)
                iounmap(i->iobase);
                list_del(&i->list);
        }
-       spin_unlock(&tis_lock);
+       mutex_unlock(&tis_lock);
 #ifdef CONFIG_PNP
        if (!force) {
                pnp_unregister_driver(&tis_pnp_driver);