| Message ID | 1424305744-16300-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index cab020a..cceb863 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -1810,14 +1810,15 @@ void pinctrl_unregister(struct pinctrl_dev *pctldev) if (pctldev == NULL) return; - mutex_lock(&pinctrldev_list_mutex); mutex_lock(&pctldev->mutex); - pinctrl_remove_device_debugfs(pctldev); + mutex_unlock(&pctldev->mutex); if (!IS_ERR(pctldev->p)) pinctrl_put(pctldev->p); + mutex_lock(&pinctrldev_list_mutex); + mutex_lock(&pctldev->mutex); /* TODO: check that no pinmuxes are still active? */ list_del(&pctldev->node); /* Destroy descriptor tree */
This is a note to let you know that I have just added a patch titled pinctrl: Fix two deadlocks to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue This patch is scheduled to be released in version 3.13.11-ckt16. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.13.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ------ From 6cfaac6a912bec4cdc24d6e29546d9e73b0312b0 Mon Sep 17 00:00:00 2001 From: Jim Lin <jilin@nvidia.com> Date: Thu, 8 Jan 2015 20:25:05 +0800 Subject: pinctrl: Fix two deadlocks commit db93facfb0ef542aa5d8079e47580b3e669a4d82 upstream. This patch is to fix two deadlock cases. Deadlock 1: CPU #1 pinctrl_register-> pinctrl_get -> create_pinctrl (Holding lock pinctrl_maps_mutex) -> get_pinctrl_dev_from_devname (Trying to acquire lock pinctrldev_list_mutex) CPU #0 pinctrl_unregister (Holding lock pinctrldev_list_mutex) -> pinctrl_put ->> pinctrl_free -> pinctrl_dt_free_maps -> pinctrl_unregister_map (Trying to acquire lock pinctrl_maps_mutex) Simply to say CPU#1 is holding lock A and trying to acquire lock B, CPU#0 is holding lock B and trying to acquire lock A. Deadlock 2: CPU #3 pinctrl_register-> pinctrl_get -> create_pinctrl (Holding lock pinctrl_maps_mutex) -> get_pinctrl_dev_from_devname (Trying to acquire lock pinctrldev_list_mutex) CPU #2 pinctrl_unregister (Holding lock pctldev->mutex) -> pinctrl_put ->> pinctrl_free -> pinctrl_dt_free_maps -> pinctrl_unregister_map (Trying to acquire lock pinctrl_maps_mutex) CPU #0 tegra_gpio_request (Holding lock pinctrldev_list_mutex) -> pinctrl_get_device_gpio_range (Trying to acquire lock pctldev->mutex) Simply to say CPU#3 is holding lock A and trying to acquire lock D, CPU#2 is holding lock B and trying to acquire lock A, CPU#0 is holding lock D and trying to acquire lock B. Signed-off-by: Jim Lin <jilin@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/pinctrl/core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) -- 1.9.1