[PATCH v1 1/1] Revert "pinctrl: avoid unsafe code pattern in find_pinctrl()"

From: Andy Shevchenko
Date: Tue Oct 17 2023 - 10:18:15 EST


The commit breaks MMC enumeration on the Intel Merrifield
plaform.

Before:
[ 36.439057] mmc0: SDHCI controller on PCI [0000:00:01.0] using ADMA
[ 36.450924] mmc2: SDHCI controller on PCI [0000:00:01.3] using ADMA
[ 36.459355] mmc1: SDHCI controller on PCI [0000:00:01.2] using ADMA
[ 36.706399] mmc0: new DDR MMC card at address 0001
[ 37.058972] mmc2: new ultra high speed DDR50 SDIO card at address 0001
[ 37.278977] mmcblk0: mmc0:0001 H4G1d 3.64 GiB
[ 37.297300] mmcblk0: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10

After:
[ 36.436704] mmc2: SDHCI controller on PCI [0000:00:01.3] using ADMA
[ 36.436720] mmc1: SDHCI controller on PCI [0000:00:01.0] using ADMA
[ 36.463685] mmc0: SDHCI controller on PCI [0000:00:01.2] using ADMA
[ 36.720627] mmc1: new DDR MMC card at address 0001
[ 37.068181] mmc2: new ultra high speed DDR50 SDIO card at address 0001
[ 37.279998] mmcblk1: mmc1:0001 H4G1d 3.64 GiB
[ 37.302670] mmcblk1: p1 p2 p3 p4 p5 p6 p7 p8 p9 p10

This reverts commit c153a4edff6ab01370fcac8e46f9c89cca1060c2.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/pinctrl/core.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index e2f7519bef04..e9dc9638120a 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -1022,20 +1022,17 @@ static int add_setting(struct pinctrl *p, struct pinctrl_dev *pctldev,

static struct pinctrl *find_pinctrl(struct device *dev)
{
- struct pinctrl *entry, *p = NULL;
+ struct pinctrl *p;

mutex_lock(&pinctrl_list_mutex);
-
- list_for_each_entry(entry, &pinctrl_list, node) {
- if (entry->dev == dev) {
- p = entry;
- kref_get(&p->users);
- break;
+ list_for_each_entry(p, &pinctrl_list, node)
+ if (p->dev == dev) {
+ mutex_unlock(&pinctrl_list_mutex);
+ return p;
}
- }

mutex_unlock(&pinctrl_list_mutex);
- return p;
+ return NULL;
}

static void pinctrl_free(struct pinctrl *p, bool inlist);
@@ -1143,6 +1140,7 @@ struct pinctrl *pinctrl_get(struct device *dev)
p = find_pinctrl(dev);
if (p) {
dev_dbg(dev, "obtain a copy of previously claimed pinctrl\n");
+ kref_get(&p->users);
return p;
}

--
2.40.0.1.gaa8946217a0b