soc: imx: gpcv2: Do not pass static memory as platform data
authorAndrey Smirnov <andrew.smirnov@gmail.com>
Tue, 10 Apr 2018 18:32:09 +0000 (11:32 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 3 Aug 2018 05:50:40 +0000 (07:50 +0200)
[ Upstream commit 050f810e238f268670f14a8f8b793ba2dbf2e92f ]

Platform device core assumes the ownership of dev.platform_data as
well as that it is dynamically allocated and it will try to kfree it
as a part of platform_device_release(). Change the code to use
platform_device_add_data() n instead of a pointer to a static memory
to avoid causing a BUG() when calling platform_device_put().

The problem can be reproduced by artificially enabling the error path
of platform_device_add() call (around line 357).

Note that this change also allows us to constify imx7_pgc_domains,
since we no longer need to be able to modify it.

Cc: Stefan Agner <stefan@agner.ch>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/soc/imx/gpcv2.c

index afc7ecc..f4e3bd4 100644 (file)
@@ -155,7 +155,7 @@ static int imx7_gpc_pu_pgc_sw_pdn_req(struct generic_pm_domain *genpd)
        return imx7_gpc_pu_pgc_sw_pxx_req(genpd, false);
 }
 
-static struct imx7_pgc_domain imx7_pgc_domains[] = {
+static const struct imx7_pgc_domain imx7_pgc_domains[] = {
        [IMX7_POWER_DOMAIN_MIPI_PHY] = {
                .genpd = {
                        .name      = "mipi-phy",
@@ -321,11 +321,6 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
                        continue;
                }
 
-               domain = &imx7_pgc_domains[domain_index];
-               domain->regmap = regmap;
-               domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
-               domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
-
                pd_pdev = platform_device_alloc("imx7-pgc-domain",
                                                domain_index);
                if (!pd_pdev) {
@@ -334,7 +329,20 @@ static int imx_gpcv2_probe(struct platform_device *pdev)
                        return -ENOMEM;
                }
 
-               pd_pdev->dev.platform_data = domain;
+               ret = platform_device_add_data(pd_pdev,
+                                              &imx7_pgc_domains[domain_index],
+                                              sizeof(imx7_pgc_domains[domain_index]));
+               if (ret) {
+                       platform_device_put(pd_pdev);
+                       of_node_put(np);
+                       return ret;
+               }
+
+               domain = pd_pdev->dev.platform_data;
+               domain->regmap = regmap;
+               domain->genpd.power_on  = imx7_gpc_pu_pgc_sw_pup_req;
+               domain->genpd.power_off = imx7_gpc_pu_pgc_sw_pdn_req;
+
                pd_pdev->dev.parent = dev;
                pd_pdev->dev.of_node = np;