| Message ID | 20210701234317.26393-1-digetx@gmail.com |
|---|---|
| Headers | show |
| Series | Add OTG mode support to Tegra USB PHY, SMB347 and Nexus 7 | expand |
On 21-07-02 02:43:10, Dmitry Osipenko wrote: > The HNP work can be re-scheduled while it's still in-fly. This results in > re-initialization of the busy work, resetting the hrtimer's list node of > the work and crashing kernel with null dereference within kernel/timer > once work's timer is expired. It's very easy to trigger this problem by > re-plugging USB cable quickly. Initialize HNP work only once to fix this > trouble. Fully OTG compliance support has not maintained for years, what's the use case you still want to use? Peter > > Cc: stable@vger.kernel.org > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/usb/common/usb-otg-fsm.c | 6 +++++- > include/linux/usb/otg-fsm.h | 1 + > 2 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/common/usb-otg-fsm.c b/drivers/usb/common/usb-otg-fsm.c > index 3740cf95560e..0697fde51d00 100644 > --- a/drivers/usb/common/usb-otg-fsm.c > +++ b/drivers/usb/common/usb-otg-fsm.c > @@ -193,7 +193,11 @@ static void otg_start_hnp_polling(struct otg_fsm *fsm) > if (!fsm->host_req_flag) > return; > > - INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work); > + if (!fsm->hnp_work_inited) { > + INIT_DELAYED_WORK(&fsm->hnp_polling_work, otg_hnp_polling_work); > + fsm->hnp_work_inited = true; > + } > + > schedule_delayed_work(&fsm->hnp_polling_work, > msecs_to_jiffies(T_HOST_REQ_POLL)); > } > diff --git a/include/linux/usb/otg-fsm.h b/include/linux/usb/otg-fsm.h > index 3aee78dda16d..784659d4dc99 100644 > --- a/include/linux/usb/otg-fsm.h > +++ b/include/linux/usb/otg-fsm.h > @@ -196,6 +196,7 @@ struct otg_fsm { > struct mutex lock; > u8 *host_req_flag; > struct delayed_work hnp_polling_work; > + bool hnp_work_inited; > bool state_changed; > }; > > -- > 2.30.2 > -- Thanks, Peter Chen
03.07.2021 14:08, Peter Chen пишет: > On 21-07-02 02:43:10, Dmitry Osipenko wrote: >> The HNP work can be re-scheduled while it's still in-fly. This results in >> re-initialization of the busy work, resetting the hrtimer's list node of >> the work and crashing kernel with null dereference within kernel/timer >> once work's timer is expired. It's very easy to trigger this problem by >> re-plugging USB cable quickly. Initialize HNP work only once to fix this >> trouble. > > Fully OTG compliance support has not maintained for years, what's the use case you > still want to use? I don't have any use case for it, but I had CONFIG_USB_OTG_FSM=y and it was crashing kernel badly. The OTG works perfectly fine without the FSM.
On 21-07-03 20:22:38, Dmitry Osipenko wrote: > 03.07.2021 14:08, Peter Chen пишет: > > On 21-07-02 02:43:10, Dmitry Osipenko wrote: > >> The HNP work can be re-scheduled while it's still in-fly. This results in > >> re-initialization of the busy work, resetting the hrtimer's list node of > >> the work and crashing kernel with null dereference within kernel/timer > >> once work's timer is expired. It's very easy to trigger this problem by > >> re-plugging USB cable quickly. Initialize HNP work only once to fix this > >> trouble. > > > > Fully OTG compliance support has not maintained for years, what's the use case you > > still want to use? > > I don't have any use case for it, but I had CONFIG_USB_OTG_FSM=y and it > was crashing kernel badly. The OTG works perfectly fine without the FSM. You could add below at your dts to disable OTG FSM: hnp-disable srp-disable adp-disable Since there are no users for OTG FSM, it hasn't maintained for years, I am not sure if it still works OK. If I remember correctly, the VBUS will be off if you enable HNP, and the device at the host port will be disconnected, that's may not your expectation.
05.07.2021 05:21, Peter Chen пишет: > On 21-07-03 20:22:38, Dmitry Osipenko wrote: >> 03.07.2021 14:08, Peter Chen пишет: >>> On 21-07-02 02:43:10, Dmitry Osipenko wrote: >>>> The HNP work can be re-scheduled while it's still in-fly. This results in >>>> re-initialization of the busy work, resetting the hrtimer's list node of >>>> the work and crashing kernel with null dereference within kernel/timer >>>> once work's timer is expired. It's very easy to trigger this problem by >>>> re-plugging USB cable quickly. Initialize HNP work only once to fix this >>>> trouble. >>> >>> Fully OTG compliance support has not maintained for years, what's the use case you >>> still want to use? >> >> I don't have any use case for it, but I had CONFIG_USB_OTG_FSM=y and it >> was crashing kernel badly. The OTG works perfectly fine without the FSM. > > You could add below at your dts to disable OTG FSM: > hnp-disable > srp-disable > adp-disable > > Since there are no users for OTG FSM, it hasn't maintained for years, > I am not sure if it still works OK. If I remember correctly, the VBUS > will be off if you enable HNP, and the device at the host port will be > disconnected, that's may not your expectation. > Since OTG FSM is known to be in a bad shape, could you please make a patch to remove it? I hope it's not enabled by default in a distro kernels.. oh no, CONFIG_USB_OTG_FSM=y at least in ArchLinux [1]. [1] https://archlinuxarm.org/packages/armv7h/linux-armv7/files/config I think we should fix that hrtimer bug, beackport the fix into stable kernels and then remove OTG FSM. Does this sound good to you?
Hi, This series adds USB OTG mode support to the NVIDIA Tegra USB PHY driver, SMB347 charger driver and Nexus 7 tablet. Changelog: v2: - The PHY's interrupt is now enabled from PHY's set_wakeup() callback. It prevents getting a spurious interrupt during the CI driver probe time. Dmitry Osipenko (12): dt-bindings: phy: tegra20-usb-phy: Convert to schema dt-bindings: phy: tegra20-usb-phy: Document properties needed for OTG mode soc/tegra: pmc: Expose USB regmap to all SoCs usb: phy: tegra: Support OTG mode programming usb: otg-fsm: Fix hrtimer list corruption dt-bindings: power: supply: smb347-charger: Document USB VBUS regulator power: supply: smb347-charger: Make smb347_set_writable() IRQ-safe power: supply: smb347-charger: Remove caching of charger state power: supply: smb347-charger: Implement USB VBUS regulator arm64: tegra132: Add new properties to USB PHY device-tree node ARM: tegra: Add new properties to USB PHY device-tree nodes ARM: tegra: nexus7: Enable USB OTG mode .../bindings/phy/nvidia,tegra20-usb-phy.txt | 74 ---- .../bindings/phy/nvidia,tegra20-usb-phy.yaml | 377 ++++++++++++++++++ .../power/supply/summit,smb347-charger.yaml | 28 ++ arch/arm/boot/dts/tegra114.dtsi | 6 + arch/arm/boot/dts/tegra124.dtsi | 9 + arch/arm/boot/dts/tegra20.dtsi | 9 + .../tegra30-asus-nexus7-grouper-common.dtsi | 25 +- arch/arm/boot/dts/tegra30.dtsi | 9 + arch/arm64/boot/dts/nvidia/tegra132.dtsi | 9 + drivers/power/supply/Kconfig | 1 + drivers/power/supply/smb347-charger.c | 259 +++++++++++- drivers/soc/tegra/pmc.c | 6 +- drivers/usb/common/usb-otg-fsm.c | 6 +- drivers/usb/phy/phy-tegra-usb.c | 202 +++++++++- .../dt-bindings/power/summit,smb347-charger.h | 4 + include/linux/usb/otg-fsm.h | 1 + include/linux/usb/tegra_usb_phy.h | 5 + 17 files changed, 926 insertions(+), 104 deletions(-) delete mode 100644 Documentation/devicetree/bindings/phy/nvidia,tegra20-usb-phy.txt create mode 100644 Documentation/devicetree/bindings/phy/nvidia,tegra20-usb-phy.yaml