[PATCH 3.10 031/139] PM / Domains: Fix unsafe iteration over modified list of device links

[Willy Tarreau]

From: Krzysztof Kozlowski <krzk@xxxxxxxxxx>

commit c6e83cac3eda5f7dd32ee1453df2f7abb5c6cd46 upstream.

pm_genpd_remove_subdomain() iterates over domain's master_links list and
removes matching element thus it has to use safe version of list
iteration.

Fixes: f721889ff65a ("PM / Domains: Support for generic I/O PM domains (v8)")
Cc: 3.1+ <stable@xxxxxxxxxxxxxxx> 
Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Acked-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Willy Tarreau <w@xxxxxx>
---
 drivers/base/power/domain.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c
index 7072404..8d73f99 100644
--- a/drivers/base/power/domain.c
+++ b/drivers/base/power/domain.c
@@ -1692,7 +1692,7 @@ int pm_genpd_add_subdomain_names(const char *master_name,
 int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
 			      struct generic_pm_domain *subdomain)
 {
-	struct gpd_link *link;
+	struct gpd_link *l, *link;
 	int ret = -EINVAL;
 
 	if (IS_ERR_OR_NULL(genpd) || IS_ERR_OR_NULL(subdomain))
@@ -1701,7 +1701,7 @@ int pm_genpd_remove_subdomain(struct generic_pm_domain *genpd,
  start:
 	genpd_acquire_lock(genpd);
 
-	list_for_each_entry(link, &genpd->master_links, master_node) {
+	list_for_each_entry_safe(link, l, &genpd->master_links, master_node) {
 		if (link->slave != subdomain)
 			continue;
 
-- 
2.8.0.rc2.1.gbe9624a