From mboxrd@z Thu Jan 1 00:00:00 1970 From: akpm@linux-foundation.org Subject: [merged] fix-pca953x-set_type-scheduling-while-atomic-bug.patch removed from -mm tree Date: Wed, 28 Apr 2010 11:03:06 -0400 Message-ID: <201004281804.o3SI4d1e010974@imap1.linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from smtp1.linux-foundation.org ([140.211.169.13]:50061 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756109Ab0D1SEy (ORCPT ); Wed, 28 Apr 2010 14:04:54 -0400 Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: maz@misterjones.org, bgat@billgatliff.com, eric.y.miao@gmail.com, mm-commits@vger.kernel.org The patch titled gpio: fix pca953x set_type 'scheduling while atomic' bug has been removed from the -mm tree. Its filename was fix-pca953x-set_type-scheduling-while-atomic-bug.patch This patch was dropped because it was merged into mainline or a subsystem tree The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: gpio: fix pca953x set_type 'scheduling while atomic' bug From: Marc Zyngier Bill Gatliff reported the following bug when using the irq_chip facility of the pca953x driver on a PPC platform: BUG: scheduling while atomic: insmod/1530/0x00000002 He traced it back to an i2c transaction in pca953x_irq_set_type(), which can be called with interrupt disabled (from __setup_irq()). As the i2c controller can sleep while sending a message, this qualifies as a bad idea. This patch moves the i2c transaction to pca953x_irq_bus_sync_unlock(), where it is actually safe to send an i2c message. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Marc Zyngier Reported-by: Bill Gatliff Cc: Eric Miao Signed-off-by: Andrew Morton --- drivers/gpio/pca953x.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff -puN drivers/gpio/pca953x.c~fix-pca953x-set_type-scheduling-while-atomic-bug drivers/gpio/pca953x.c --- a/drivers/gpio/pca953x.c~fix-pca953x-set_type-scheduling-while-atomic-bug +++ a/drivers/gpio/pca953x.c @@ -252,6 +252,18 @@ static void pca953x_irq_bus_lock(unsigne static void pca953x_irq_bus_sync_unlock(unsigned int irq) { struct pca953x_chip *chip = get_irq_chip_data(irq); + uint16_t new_irqs; + uint16_t level; + + /* Look for any newly setup interrupt */ + new_irqs = chip->irq_trig_fall | chip->irq_trig_raise; + new_irqs &= ~chip->reg_direction; + + while (new_irqs) { + level = __ffs(new_irqs); + pca953x_gpio_direction_input(&chip->gpio_chip, level); + new_irqs &= ~(1 << level); + } mutex_unlock(&chip->irq_lock); } @@ -278,7 +290,7 @@ static int pca953x_irq_set_type(unsigned else chip->irq_trig_raise &= ~mask; - return pca953x_gpio_direction_input(&chip->gpio_chip, level); + return 0; } static struct irq_chip pca953x_irq_chip = { _ Patches currently in -mm which might be from maz@misterjones.org are origin.patch linux-next.patch rtc-ds1302-add-some-abstraction-for-new-platform-support.patch gpio-add-interrupt-handling-capability-to-max732x.patch gpio-max732x-fix-input-configuration-for-open-drain-pins.patch