From 82b34b0800af8c9fc9988c290cdc813e0ca0df31 Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Mon, 13 Feb 2023 20:19:22 +0530 Subject: PCI: pciehp: Add Qualcomm quirk for Command Completed erratum The Qualcomm PCI bridge device (Device ID 0x010e) found in chipsets such as SC8280XP used in Lenovo Thinkpad X13s, does not set the Command Completed bit unless writes to the Slot Command register change "Control" bits. This results in timeouts like below during boot and resume from suspend: pcieport 0002:00:00.0: pciehp: Timeout on hotplug command 0x03c0 (issued 2020 msec ago) ... pcieport 0002:00:00.0: pciehp: Timeout on hotplug command 0x13f1 (issued 107724 msec ago) Add the device to the Command Completed quirk to mark commands "completed" immediately unless they change the "Control" bits. Link: https://lore.kernel.org/r/20230213144922.89982-1-manivannan.sadhasivam@linaro.org Signed-off-by: Manivannan Sadhasivam Signed-off-by: Bjorn Helgaas --- drivers/pci/hotplug/pciehp_hpc.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/pci') diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 10e9670eea0b..f8c70115b691 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -1088,6 +1088,8 @@ static void quirk_cmd_compl(struct pci_dev *pdev) } DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); +DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x010e, + PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0110, PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0400, -- cgit v1.2.3 From 74ff8864cc842be994853095dba6db48e716400a Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Fri, 20 Jan 2023 10:19:02 +0100 Subject: PCI: hotplug: Allow marking devices as disconnected during bind/unbind On surprise removal, pciehp_unconfigure_device() and acpiphp's trim_stale_devices() call pci_dev_set_disconnected() to mark removed devices as permanently offline. Thereby, the PCI core and drivers know to skip device accesses. However pci_dev_set_disconnected() takes the device_lock and thus waits for a concurrent driver bind or unbind to complete. As a result, the driver's ->probe and ->remove hooks have no chance to learn that the device is gone. That doesn't make any sense, so drop the device_lock and instead use atomic xchg() and cmpxchg() operations to update the device state. As a byproduct, an AB-BA deadlock reported by Anatoli is fixed which occurs on surprise removal with AER concurrently performing a bus reset. AER bus reset: INFO: task irq/26-aerdrv:95 blocked for more than 120 seconds. Tainted: G W 6.2.0-rc3-custom-norework-jan11+ schedule rwsem_down_write_slowpath down_write_nested pciehp_reset_slot # acquires reset_lock pci_reset_hotplug_slot pci_slot_reset # acquires device_lock pci_bus_error_reset aer_root_reset pcie_do_recovery aer_process_err_devices aer_isr pciehp surprise removal: INFO: task irq/26-pciehp:96 blocked for more than 120 seconds. Tainted: G W 6.2.0-rc3-custom-norework-jan11+ schedule_preempt_disabled __mutex_lock mutex_lock_nested pci_dev_set_disconnected # acquires device_lock pci_walk_bus pciehp_unconfigure_device pciehp_disable_slot pciehp_handle_presence_or_link_change pciehp_ist # acquires reset_lock Link: https://bugzilla.kernel.org/show_bug.cgi?id=215590 Fixes: a6bd101b8f84 ("PCI: Unify device inaccessible") Link: https://lore.kernel.org/r/3dc88ea82bdc0e37d9000e413d5ebce481cbd629.1674205689.git.lukas@wunner.de Reported-by: Anatoli Antonovitch Signed-off-by: Lukas Wunner Signed-off-by: Bjorn Helgaas Cc: stable@vger.kernel.org # v4.20+ Cc: Keith Busch --- drivers/pci/pci.h | 43 +++++++++++++------------------------------ 1 file changed, 13 insertions(+), 30 deletions(-) (limited to 'drivers/pci') diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 9ed3b5550043..5d5a44aaafe8 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -310,53 +310,36 @@ struct pci_sriov { * @dev: PCI device to set new error_state * @new: the state we want dev to be in * - * Must be called with device_lock held. + * If the device is experiencing perm_failure, it has to remain in that state. + * Any other transition is allowed. * * Returns true if state has been changed to the requested state. */ static inline bool pci_dev_set_io_state(struct pci_dev *dev, pci_channel_state_t new) { - bool changed = false; + pci_channel_state_t old; - device_lock_assert(&dev->dev); switch (new) { case pci_channel_io_perm_failure: - switch (dev->error_state) { - case pci_channel_io_frozen: - case pci_channel_io_normal: - case pci_channel_io_perm_failure: - changed = true; - break; - } - break; + xchg(&dev->error_state, pci_channel_io_perm_failure); + return true; case pci_channel_io_frozen: - switch (dev->error_state) { - case pci_channel_io_frozen: - case pci_channel_io_normal: - changed = true; - break; - } - break; + old = cmpxchg(&dev->error_state, pci_channel_io_normal, + pci_channel_io_frozen); + return old != pci_channel_io_perm_failure; case pci_channel_io_normal: - switch (dev->error_state) { - case pci_channel_io_frozen: - case pci_channel_io_normal: - changed = true; - break; - } - break; + old = cmpxchg(&dev->error_state, pci_channel_io_frozen, + pci_channel_io_normal); + return old != pci_channel_io_perm_failure; + default: + return false; } - if (changed) - dev->error_state = new; - return changed; } static inline int pci_dev_set_disconnected(struct pci_dev *dev, void *unused) { - device_lock(&dev->dev); pci_dev_set_io_state(dev, pci_channel_io_perm_failure); - device_unlock(&dev->dev); return 0; } -- cgit v1.2.3