From dd13c86b0dae86efdde98119ffd7348e80719ade Mon Sep 17 00:00:00 2001 From: Ben Chan Date: Wed, 6 Jun 2012 23:01:26 -0700 Subject: [PATCH] staging: gdm72xx: Fix spinlock recursion on gdm_usb_send_complete This patch fixes a spinlock recursion bug on several call sites of gdm_usb_send_complete by not calling spin_lock_irqsave on urb->context->tx_cxt->lock when the lock has already been acquired. Signed-off-by: Ben Chan Cc: Sage Ahn Signed-off-by: Greg Kroah-Hartman --- drivers/staging/gdm72xx/gdm_usb.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/drivers/staging/gdm72xx/gdm_usb.c b/drivers/staging/gdm72xx/gdm_usb.c index e201b341e52f..646e0ace91ec 100644 --- a/drivers/staging/gdm72xx/gdm_usb.c +++ b/drivers/staging/gdm72xx/gdm_usb.c @@ -270,7 +270,7 @@ static void release_usb(struct usbwm_dev *udev) } } -static void gdm_usb_send_complete(struct urb *urb) +static void gdm_usb_send_complete_impl(struct urb *urb, bool need_lock) { struct usb_tx *t = urb->context; struct tx_cxt *tx = t->tx_cxt; @@ -282,7 +282,8 @@ static void gdm_usb_send_complete(struct urb *urb) if (urb->status == -ECONNRESET) return; - spin_lock_irqsave(&tx->lock, flags); + if (need_lock) + spin_lock_irqsave(&tx->lock, flags); if (t->callback) t->callback(t->cb_data); @@ -296,7 +297,18 @@ static void gdm_usb_send_complete(struct urb *urb) else free_tx_struct(t); - spin_unlock_irqrestore(&tx->lock, flags); + if (need_lock) + spin_unlock_irqrestore(&tx->lock, flags); +} + +static void gdm_usb_send_complete(struct urb *urb) +{ + gdm_usb_send_complete_impl(urb, true); +} + +static void gdm_usb_send_complete_no_lock(struct urb *urb) +{ + gdm_usb_send_complete_impl(urb, false); } static int gdm_usb_send(void *priv_dev, void *data, int len, @@ -411,7 +423,7 @@ out: send_fail: t->callback = NULL; - gdm_usb_send_complete(t->urb); + gdm_usb_send_complete_no_lock(t->urb); spin_unlock_irqrestore(&tx->lock, flags); return ret; } @@ -540,7 +552,7 @@ static void do_pm_control(struct work_struct *work) if (ret) { t->callback = NULL; - gdm_usb_send_complete(t->urb); + gdm_usb_send_complete_no_lock(t->urb); } } } @@ -742,7 +754,7 @@ static int k_mode_thread(void *arg) if (ret) { t->callback = NULL; - gdm_usb_send_complete(t->urb); + gdm_usb_send_complete_no_lock(t->urb); } } -- 2.11.0