From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: From: Mika Westerberg To: Bjorn Helgaas Cc: Valdis Kletnieks , Lukas Wunner , "Rafael J . Wysocki" , Mika Westerberg , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org Subject: [PATCH] PCI: pcie: Call pm_runtime_no_callbacks() after device is registered Date: Mon, 23 May 2016 11:11:55 +0300 Message-Id: <1463991115-64820-1-git-send-email-mika.westerberg@linux.intel.com> In-Reply-To: <14501.1463692755@turing-police.cc.vt.edu> References: <14501.1463692755@turing-police.cc.vt.edu> List-ID: Commit 0195d2813547 ("PCI: Add runtime PM support for PCIe ports") added call to pm_runtime_no_callbacks() for each port service device to prevent them exposing unnecessary runtime PM sysfs files. However, that function tries to acquire dev->power.lock which is not yet initialized. This triggers following splat: BUG: spinlock bad magic on CPU#0, swapper/0/1 lock: 0xffff8801be2aa8e8, .magic: 00000000, .owner: /-1, .owner_cpu: 0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.6.0+ #820 0000000000000000 ffff8801beb97be0 ffffffff812cf42d 0000000000000000 ffff8801be2aa8e8 ffff8801beb97c00 ffffffff8109ee58 ffff8801be2aa8e8 ffff8801be2aa8e8 ffff8801beb97c30 ffffffff8109efd9 ffff8801be2aa8e8 Call Trace: [] dump_stack+0x4f/0x72 [] spin_dump+0x78/0xc0 [] do_raw_spin_lock+0xf9/0x150 [] _raw_spin_lock_irq+0x20/0x30 [] pm_runtime_no_callbacks+0x1e/0x40 [] pcie_port_device_register+0x1fd/0x4e0 [] pcie_portdrv_probe+0x38/0xa0 [] local_pci_probe+0x45/0xa0 [] ? pci_match_device+0xe0/0x110 [] pci_device_probe+0xdb/0x130 [] driver_probe_device+0x22c/0x440 [] __driver_attach+0xd1/0xf0 [] ? driver_probe_device+0x440/0x440 [] bus_for_each_dev+0x64/0xa0 [] driver_attach+0x1e/0x20 [] bus_add_driver+0x1eb/0x280 [] ? pcie_port_setup+0x7c/0x7c [] driver_register+0x60/0xe0 [] __pci_register_driver+0x60/0x70 [] pcie_portdrv_init+0x63/0x75 [] do_one_initcall+0xab/0x1c0 [] kernel_init_freeable+0x153/0x1d9 [] kernel_init+0xe/0x100 [] ret_from_fork+0x22/0x40 [] ? rest_init+0x90/0x90 Fix this by calling pm_runtime_no_callbacks() after device_register() just like other buses, like I2C is doing already. Reported-by: Valdis Kletnieks Tested-by: Valdis Kletnieks Suggested-by: Lukas Wunner Signed-off-by: Mika Westerberg --- drivers/pci/pcie/portdrv_core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c index 65b1a624826b..97927dfbbf5f 100644 --- a/drivers/pci/pcie/portdrv_core.c +++ b/drivers/pci/pcie/portdrv_core.c @@ -344,7 +344,6 @@ static int pcie_device_init(struct pci_dev *pdev, int service, int irq) get_descriptor_id(pci_pcie_type(pdev), service)); device->parent = &pdev->dev; device_enable_async_suspend(device); - pm_runtime_no_callbacks(device); retval = device_register(device); if (retval) { @@ -352,6 +351,8 @@ static int pcie_device_init(struct pci_dev *pdev, int service, int irq) return retval; } + pm_runtime_no_callbacks(device); + return 0; } -- 2.8.1