2019-06-05 09:04:25

by Neil Armstrong

[permalink] [raw]
Subject: [PATCH v2] phy: meson-g12a-usb3-pcie: disable locking for cr_regmap

Locking is not needed for the phy_g12a_usb3_pcie_cr_bus_read/write() and
currently it causes the following BUG because of the usage of the
regmap_read_poll_timeout() running in spinlock_irq, configured by regmap fast_io.

Simply disable locking in the cr_regmap config since it's only used from the
PHY init callback function.

BUG: sleeping function called from invalid context at drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c:85
in_atomic(): 1, irqs_disabled(): 128, pid: 60, name: kworker/3:1
[snip]
Workqueue: events deferred_probe_work_func
Call trace:
dump_backtrace+0x0/0x190
show_stack+0x14/0x20
dump_stack+0x90/0xb4
___might_sleep+0xec/0x110
__might_sleep+0x50/0x88
phy_g12a_usb3_pcie_cr_bus_addr.isra.0+0x80/0x1a8
phy_g12a_usb3_pcie_cr_bus_read+0x34/0x1d8
_regmap_read+0x60/0xe0
_regmap_update_bits+0xc4/0x110
regmap_update_bits_base+0x60/0x90
phy_g12a_usb3_pcie_init+0xdc/0x210
phy_init+0x74/0xd0
dwc3_meson_g12a_probe+0x2cc/0x4d0
platform_drv_probe+0x50/0xa0
really_probe+0x20c/0x3b8
driver_probe_device+0x68/0x150
__device_attach_driver+0xa8/0x170
bus_for_each_drv+0x64/0xc8
__device_attach+0xd8/0x158
device_initial_probe+0x10/0x18
bus_probe_device+0x90/0x98
deferred_probe_work_func+0x94/0xe8
process_one_work+0x1e0/0x338
worker_thread+0x230/0x458
kthread+0x134/0x138
ret_from_fork+0x10/0x1c

Fixes: 36077e16c050 ("phy: amlogic: Add Amlogic G12A USB3 + PCIE Combo PHY Driver")
Signed-off-by: Neil Armstrong <[email protected]>
---
drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
index 6233a7979a93..ac322d643c7a 100644
--- a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
+++ b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
@@ -188,7 +188,7 @@ static const struct regmap_config phy_g12a_usb3_pcie_cr_regmap_conf = {
.reg_read = phy_g12a_usb3_pcie_cr_bus_read,
.reg_write = phy_g12a_usb3_pcie_cr_bus_write,
.max_register = 0xffff,
- .fast_io = true,
+ .disable_locking = true,
};

static int phy_g12a_usb3_init(struct phy *phy)
--
2.21.0


2019-06-07 23:13:51

by Kevin Hilman

[permalink] [raw]
Subject: Re: [PATCH v2] phy: meson-g12a-usb3-pcie: disable locking for cr_regmap

Neil Armstrong <[email protected]> writes:

> Locking is not needed for the phy_g12a_usb3_pcie_cr_bus_read/write() and
> currently it causes the following BUG because of the usage of the
> regmap_read_poll_timeout() running in spinlock_irq, configured by regmap fast_io.
>
> Simply disable locking in the cr_regmap config since it's only used from the
> PHY init callback function.
>
> BUG: sleeping function called from invalid context at drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c:85
> in_atomic(): 1, irqs_disabled(): 128, pid: 60, name: kworker/3:1
> [snip]
> Workqueue: events deferred_probe_work_func
> Call trace:
> dump_backtrace+0x0/0x190
> show_stack+0x14/0x20
> dump_stack+0x90/0xb4
> ___might_sleep+0xec/0x110
> __might_sleep+0x50/0x88
> phy_g12a_usb3_pcie_cr_bus_addr.isra.0+0x80/0x1a8
> phy_g12a_usb3_pcie_cr_bus_read+0x34/0x1d8
> _regmap_read+0x60/0xe0
> _regmap_update_bits+0xc4/0x110
> regmap_update_bits_base+0x60/0x90
> phy_g12a_usb3_pcie_init+0xdc/0x210
> phy_init+0x74/0xd0
> dwc3_meson_g12a_probe+0x2cc/0x4d0
> platform_drv_probe+0x50/0xa0
> really_probe+0x20c/0x3b8
> driver_probe_device+0x68/0x150
> __device_attach_driver+0xa8/0x170
> bus_for_each_drv+0x64/0xc8
> __device_attach+0xd8/0x158
> device_initial_probe+0x10/0x18
> bus_probe_device+0x90/0x98
> deferred_probe_work_func+0x94/0xe8
> process_one_work+0x1e0/0x338
> worker_thread+0x230/0x458
> kthread+0x134/0x138
> ret_from_fork+0x10/0x1c
>
> Fixes: 36077e16c050 ("phy: amlogic: Add Amlogic G12A USB3 + PCIE Combo PHY Driver")
> Signed-off-by: Neil Armstrong <[email protected]>

Tested-by: Kevin Hilman <[email protected]>

2019-06-24 14:12:07

by Neil Armstrong

[permalink] [raw]
Subject: Re: [PATCH v2] phy: meson-g12a-usb3-pcie: disable locking for cr_regmap

Hi Kishon,

On 05/06/2019 11:02, Neil Armstrong wrote:
> Locking is not needed for the phy_g12a_usb3_pcie_cr_bus_read/write() and
> currently it causes the following BUG because of the usage of the
> regmap_read_poll_timeout() running in spinlock_irq, configured by regmap fast_io.
>
> Simply disable locking in the cr_regmap config since it's only used from the
> PHY init callback function.

Gentle ping,
Is the commit log right now ?

Thanks,
Neil

>
> BUG: sleeping function called from invalid context at drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c:85
> in_atomic(): 1, irqs_disabled(): 128, pid: 60, name: kworker/3:1
> [snip]
> Workqueue: events deferred_probe_work_func
> Call trace:
> dump_backtrace+0x0/0x190
> show_stack+0x14/0x20
> dump_stack+0x90/0xb4
> ___might_sleep+0xec/0x110
> __might_sleep+0x50/0x88
> phy_g12a_usb3_pcie_cr_bus_addr.isra.0+0x80/0x1a8
> phy_g12a_usb3_pcie_cr_bus_read+0x34/0x1d8
> _regmap_read+0x60/0xe0
> _regmap_update_bits+0xc4/0x110
> regmap_update_bits_base+0x60/0x90
> phy_g12a_usb3_pcie_init+0xdc/0x210
> phy_init+0x74/0xd0
> dwc3_meson_g12a_probe+0x2cc/0x4d0
> platform_drv_probe+0x50/0xa0
> really_probe+0x20c/0x3b8
> driver_probe_device+0x68/0x150
> __device_attach_driver+0xa8/0x170
> bus_for_each_drv+0x64/0xc8
> __device_attach+0xd8/0x158
> device_initial_probe+0x10/0x18
> bus_probe_device+0x90/0x98
> deferred_probe_work_func+0x94/0xe8
> process_one_work+0x1e0/0x338
> worker_thread+0x230/0x458
> kthread+0x134/0x138
> ret_from_fork+0x10/0x1con,
>
> Fixes: 36077e16c050 ("phy: amlogic: Add Amlogic G12A USB3 + PCIE Combo PHY Driver")
> Signed-off-by: Neil Armstrong <[email protected]>
> ---
> drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
> index 6233a7979a93..ac322d643c7a 100644
> --- a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
> +++ b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
> @@ -188,7 +188,7 @@ static const struct regmap_config phy_g12a_usb3_pcie_cr_regmap_conf = {
> .reg_read = phy_g12a_usb3_pcie_cr_bus_read,
> .reg_write = phy_g12a_usb3_pcie_cr_bus_write,
> .max_register = 0xffff,
> - .fast_io = true,
> + .disable_locking = true,
> };
>
> static int phy_g12a_usb3_init(struct phy *phy)
>

2019-06-25 07:22:22

by Kishon Vijay Abraham I

[permalink] [raw]
Subject: Re: [PATCH v2] phy: meson-g12a-usb3-pcie: disable locking for cr_regmap



On 24/06/19 6:30 PM, Neil Armstrong wrote:
> Hi Kishon,
>
> On 05/06/2019 11:02, Neil Armstrong wrote:
>> Locking is not needed for the phy_g12a_usb3_pcie_cr_bus_read/write() and
>> currently it causes the following BUG because of the usage of the
>> regmap_read_poll_timeout() running in spinlock_irq, configured by regmap fast_io.
>>
>> Simply disable locking in the cr_regmap config since it's only used from the
>> PHY init callback function.
>
> Gentle ping,
> Is the commit log right now ?

merged now, thanks!

-Kishon

>
> Thanks,
> Neil
>
>>
>> BUG: sleeping function called from invalid context at drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c:85
>> in_atomic(): 1, irqs_disabled(): 128, pid: 60, name: kworker/3:1
>> [snip]
>> Workqueue: events deferred_probe_work_func
>> Call trace:
>> dump_backtrace+0x0/0x190
>> show_stack+0x14/0x20
>> dump_stack+0x90/0xb4
>> ___might_sleep+0xec/0x110
>> __might_sleep+0x50/0x88
>> phy_g12a_usb3_pcie_cr_bus_addr.isra.0+0x80/0x1a8
>> phy_g12a_usb3_pcie_cr_bus_read+0x34/0x1d8
>> _regmap_read+0x60/0xe0
>> _regmap_update_bits+0xc4/0x110
>> regmap_update_bits_base+0x60/0x90
>> phy_g12a_usb3_pcie_init+0xdc/0x210
>> phy_init+0x74/0xd0
>> dwc3_meson_g12a_probe+0x2cc/0x4d0
>> platform_drv_probe+0x50/0xa0
>> really_probe+0x20c/0x3b8
>> driver_probe_device+0x68/0x150
>> __device_attach_driver+0xa8/0x170
>> bus_for_each_drv+0x64/0xc8
>> __device_attach+0xd8/0x158
>> device_initial_probe+0x10/0x18
>> bus_probe_device+0x90/0x98
>> deferred_probe_work_func+0x94/0xe8
>> process_one_work+0x1e0/0x338
>> worker_thread+0x230/0x458
>> kthread+0x134/0x138
>> ret_from_fork+0x10/0x1con,
>>
>> Fixes: 36077e16c050 ("phy: amlogic: Add Amlogic G12A USB3 + PCIE Combo PHY Driver")
>> Signed-off-by: Neil Armstrong <[email protected]>
>> ---
>> drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
>> index 6233a7979a93..ac322d643c7a 100644
>> --- a/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
>> +++ b/drivers/phy/amlogic/phy-meson-g12a-usb3-pcie.c
>> @@ -188,7 +188,7 @@ static const struct regmap_config phy_g12a_usb3_pcie_cr_regmap_conf = {
>> .reg_read = phy_g12a_usb3_pcie_cr_bus_read,
>> .reg_write = phy_g12a_usb3_pcie_cr_bus_write,
>> .max_register = 0xffff,
>> - .fast_io = true,
>> + .disable_locking = true,
>> };
>>
>> static int phy_g12a_usb3_init(struct phy *phy)
>>
>