| Message ID | 1462823000-5151-1-git-send-email-kamal@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/iio/magnetometer/ak8975.c b/drivers/iio/magnetometer/ak8975.c index b13936d..fd780bb 100644 --- a/drivers/iio/magnetometer/ak8975.c +++ b/drivers/iio/magnetometer/ak8975.c @@ -462,6 +462,8 @@ static int ak8975_setup_irq(struct ak8975_data *data) int rc; int irq; + init_waitqueue_head(&data->data_ready_queue); + clear_bit(0, &data->flags); if (client->irq) irq = client->irq; else @@ -477,8 +479,6 @@ static int ak8975_setup_irq(struct ak8975_data *data) return rc; } - init_waitqueue_head(&data->data_ready_queue); - clear_bit(0, &data->flags); data->eoc_irq = irq; return rc;
This is a note to let you know that I have just added a patch titled iio: ak8975: Fix NULL pointer exception on early interrupt to the linux-4.2.y-queue branch of the 4.2.y-ckt extended stable tree which can be found at: https://git.launchpad.net/~canonical-kernel/linux/+git/linux-stable-ckt/log/?h=linux-4.2.y-queue This patch is scheduled to be released in version 4.2.8-ckt10. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 4.2.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 7f209cc1e8b66454e0179dfafedee92d89bdcb64 Mon Sep 17 00:00:00 2001 From: Krzysztof Kozlowski <k.kozlowski@samsung.com> Date: Mon, 4 Apr 2016 14:54:59 +0900 Subject: iio: ak8975: Fix NULL pointer exception on early interrupt commit 07d2390e36ee5b3265e9cc8305f2a106c8721e16 upstream. In certain probe conditions the interrupt came right after registering the handler causing a NULL pointer exception because of uninitialized waitqueue: $ udevadm trigger i2c-gpio i2c-gpio-1: using pins 143 (SDA) and 144 (SCL) i2c-gpio i2c-gpio-3: using pins 53 (SDA) and 52 (SCL) Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = e8b38000 [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: snd_soc_i2s(+) i2c_gpio(+) snd_soc_idma snd_soc_s3c_dma snd_soc_core snd_pcm_dmaengine snd_pcm snd_timer snd soundcore ac97_bus spi_s3c64xx pwm_samsung dwc2 exynos_adc phy_exynos_usb2 exynosdrm exynos_rng rng_core rtc_s3c CPU: 0 PID: 717 Comm: data-provider-m Not tainted 4.6.0-rc1-next-20160401-00011-g1b8d87473b9e-dirty #101 Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) (...) (__wake_up_common) from [<c0379624>] (__wake_up+0x38/0x4c) (__wake_up) from [<c0a41d30>] (ak8975_irq_handler+0x28/0x30) (ak8975_irq_handler) from [<c0386720>] (handle_irq_event_percpu+0x88/0x140) (handle_irq_event_percpu) from [<c038681c>] (handle_irq_event+0x44/0x68) (handle_irq_event) from [<c0389c40>] (handle_edge_irq+0xf0/0x19c) (handle_edge_irq) from [<c0385e04>] (generic_handle_irq+0x24/0x34) (generic_handle_irq) from [<c05ee360>] (exynos_eint_gpio_irq+0x50/0x68) (exynos_eint_gpio_irq) from [<c0386720>] (handle_irq_event_percpu+0x88/0x140) (handle_irq_event_percpu) from [<c038681c>] (handle_irq_event+0x44/0x68) (handle_irq_event) from [<c0389a70>] (handle_fasteoi_irq+0xb4/0x194) (handle_fasteoi_irq) from [<c0385e04>] (generic_handle_irq+0x24/0x34) (generic_handle_irq) from [<c03860b4>] (__handle_domain_irq+0x5c/0xb4) (__handle_domain_irq) from [<c0301774>] (gic_handle_irq+0x54/0x94) (gic_handle_irq) from [<c030c910>] (__irq_usr+0x50/0x80) The bug was reproduced on exynos4412-trats2 (with a max77693 device also using i2c-gpio) after building max77693 as a module. Fixes: 94a6d5cf7caa ("iio:ak8975 Implement data ready interrupt handling") Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Tested-by: Gregor Boirie <gregor.boirie@parrot.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/iio/magnetometer/ak8975.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) -- 2.7.4