of: Fix locking vs. interrupts

The OF code uses irqsafe locks everywhere except in a handful of functions
for no obvious reasons. Since the conversion from the old rwlocks, this
now triggers lockdep warnings when used at interrupt time. At least one
driver (ibmvscsi) seems to be doing that from softirq context.

This converts the few non-irqsafe locks into irqsafe ones, making them
consistent with the rest of the code.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Grant Likely <grant.likely@linaro.org>

diff --git a/arch/sparc/kernel/prom_common.c b/arch/sparc/kernel/prom_common.c
index 9f20566b0773a8b17003176c0159aea062935f39..79cc0d1a477d0dbeb80178fb977c0d9e04bd24f5 100644 (file)
--- a/arch/sparc/kernel/prom_common.c
+++ b/arch/sparc/kernel/prom_common.c
@@ -54,6 +54,7 @@ EXPORT_SYMBOL(of_set_property_mutex);
 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
 {
        struct property **prevp;
+       unsigned long flags;
        void *new_val;
        int err;
 
@@ -64,7 +65,7 @@ int of_set_property(struct device_node *dp, const char *name, void *val, int len
        err = -ENODEV;
 
        mutex_lock(&of_set_property_mutex);
-       raw_spin_lock(&devtree_lock);
+       raw_spin_lock_irqsave(&devtree_lock, flags);
        prevp = &dp->properties;
        while (*prevp) {
                struct property *prop = *prevp;
@@ -91,7 +92,7 @@ int of_set_property(struct device_node *dp, const char *name, void *val, int len
                }
                prevp = &(*prevp)->next;
        }
-       raw_spin_unlock(&devtree_lock);
+       raw_spin_unlock_irqrestore(&devtree_lock, flags);
        mutex_unlock(&of_set_property_mutex);
 
        /* XXX Upate procfs if necessary... */

diff --git a/drivers/of/base.c b/drivers/of/base.c
index f53b992f060a1eaa50fb9de6afda8edb6bf49e69..a6f584a7f4a13f2842663c98d807e9b38b2cf89f 100644 (file)
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -192,14 +192,15 @@ EXPORT_SYMBOL(of_find_property);
 struct device_node *of_find_all_nodes(struct device_node *prev)
 {
        struct device_node *np;
+       unsigned long flags;
 
-       raw_spin_lock(&devtree_lock);
+       raw_spin_lock_irqsave(&devtree_lock, flags);
        np = prev ? prev->allnext : of_allnodes;
        for (; np != NULL; np = np->allnext)
                if (of_node_get(np))
                        break;
        of_node_put(prev);
-       raw_spin_unlock(&devtree_lock);
+       raw_spin_unlock_irqrestore(&devtree_lock, flags);
        return np;
 }
 EXPORT_SYMBOL(of_find_all_nodes);
@@ -421,8 +422,9 @@ struct device_node *of_get_next_available_child(const struct device_node *node,
        struct device_node *prev)
 {
        struct device_node *next;
+       unsigned long flags;
 
-       raw_spin_lock(&devtree_lock);
+       raw_spin_lock_irqsave(&devtree_lock, flags);
        next = prev ? prev->sibling : node->child;
        for (; next; next = next->sibling) {
                if (!__of_device_is_available(next))
@@ -431,7 +433,7 @@ struct device_node *of_get_next_available_child(const struct device_node *node,
                        break;
        }
        of_node_put(prev);
-       raw_spin_unlock(&devtree_lock);
+       raw_spin_unlock_irqrestore(&devtree_lock, flags);
        return next;
 }
 EXPORT_SYMBOL(of_get_next_available_child);
@@ -735,13 +737,14 @@ EXPORT_SYMBOL_GPL(of_modalias_node);
 struct device_node *of_find_node_by_phandle(phandle handle)
 {
        struct device_node *np;
+       unsigned long flags;
 
-       raw_spin_lock(&devtree_lock);
+       raw_spin_lock_irqsave(&devtree_lock, flags);
        for (np = of_allnodes; np; np = np->allnext)
                if (np->phandle == handle)
                        break;
        of_node_get(np);
-       raw_spin_unlock(&devtree_lock);
+       raw_spin_unlock_irqrestore(&devtree_lock, flags);
        return np;
 }
 EXPORT_SYMBOL(of_find_node_by_phandle);