This is a note to let you know that I've just added the patch titled
usb: chipidea: core: fix possible concurrent when switch role
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
usb-chipidea-core-fix-possible-concurrent-when-switch-role.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 451b15ed138ec15bffbebb58a00ebdd884c3e659 Mon Sep 17 00:00:00 2001
From: Xu Yang <xu.yang_2@xxxxxxx>
Date: Fri, 17 Mar 2023 14:15:16 +0800
Subject: usb: chipidea: core: fix possible concurrent when switch role
From: Xu Yang <xu.yang_2@xxxxxxx>
commit 451b15ed138ec15bffbebb58a00ebdd884c3e659 upstream.
The user may call role_store() when driver is handling
ci_handle_id_switch() which is triggerred by otg event or power lost
event. Unfortunately, the controller may go into chaos in this case.
Fix this by protecting it with mutex lock.
Fixes: a932a8041ff9 ("usb: chipidea: core: add sysfs group")
cc: <stable@xxxxxxxxxxxxxxx>
Acked-by: Peter Chen <peter.chen@xxxxxxxxxx>
Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
Link: https://lore.kernel.org/r/20230317061516.2451728-2-xu.yang_2@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/chipidea/ci.h | 2 ++
drivers/usb/chipidea/core.c | 8 +++++++-
drivers/usb/chipidea/otg.c | 5 ++++-
3 files changed, 13 insertions(+), 2 deletions(-)
--- a/drivers/usb/chipidea/ci.h
+++ b/drivers/usb/chipidea/ci.h
@@ -205,6 +205,7 @@ struct hw_bank {
* @in_lpm: if the core in low power mode
* @wakeup_int: if wakeup interrupt occur
* @rev: The revision number for controller
+ * @mutex: protect code from concorrent running when doing role switch
*/
struct ci_hdrc {
struct device *dev;
@@ -259,6 +260,7 @@ struct ci_hdrc {
bool in_lpm;
bool wakeup_int;
enum ci_revision rev;
+ struct mutex mutex;
};
static inline struct ci_role_driver *ci_role(struct ci_hdrc *ci)
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -878,8 +878,12 @@ static ssize_t ci_role_store(struct devi
if (role == CI_ROLE_END)
return -EINVAL;
- if (role == ci->role)
+ mutex_lock(&ci->mutex);
+
+ if (role == ci->role) {
+ mutex_unlock(&ci->mutex);
return n;
+ }
pm_runtime_get_sync(dev);
disable_irq(ci->irq);
@@ -889,6 +893,7 @@ static ssize_t ci_role_store(struct devi
ci_handle_vbus_change(ci);
enable_irq(ci->irq);
pm_runtime_put_sync(dev);
+ mutex_unlock(&ci->mutex);
return (ret == 0) ? n : ret;
}
@@ -927,6 +932,7 @@ static int ci_hdrc_probe(struct platform
return -ENOMEM;
spin_lock_init(&ci->lock);
+ mutex_init(&ci->mutex);
ci->dev = dev;
ci->platdata = dev_get_platdata(dev);
ci->imx28_write_fix = !!(ci->platdata->flags &
--- a/drivers/usb/chipidea/otg.c
+++ b/drivers/usb/chipidea/otg.c
@@ -167,8 +167,10 @@ static int hw_wait_vbus_lower_bsv(struct
static void ci_handle_id_switch(struct ci_hdrc *ci)
{
- enum ci_role role = ci_otg_role(ci);
+ enum ci_role role;
+ mutex_lock(&ci->mutex);
+ role = ci_otg_role(ci);
if (role != ci->role) {
dev_dbg(ci->dev, "switching from %s to %s\n",
ci_role(ci)->name, ci->roles[role]->name);
@@ -191,6 +193,7 @@ static void ci_handle_id_switch(struct c
if (role == CI_ROLE_GADGET)
ci_handle_vbus_change(ci);
}
+ mutex_unlock(&ci->mutex);
}
/**
* ci_otg_work - perform otg (vbus/id) event handle
Patches currently in stable-queue which might be from xu.yang_2@xxxxxxx are
queue-4.14/usb-chipidea-core-fix-possible-concurrent-when-switch-role.patch
queue-4.14/usb-chipdea-core-fix-return-einval-if-request-role-is-the-same-with-current-role.patch
