From: Alan Jenkins Date: Mon, 29 Jun 2009 08:40:07 +0000 (+0100) Subject: eeepc-laptop: fix hot-unplug on resume X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=7334546a52c6764df120459509b1f803a073eacc;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git eeepc-laptop: fix hot-unplug on resume OOPS on resume when the wireless adaptor is disabled during suspend was introduced by "eeepc-laptop: read rfkill soft-blocked state on resume". Unable to handle kernel NULL pointer dereference Process s2disk Tainted: G W IP: klist_put Call trace: ? klist_del ? device_del ? device_unregister ? pci_stop_dev ? pci_stop_bus ? pci_remove_device ? eeepc_rfkill_hotplug [eeepc_laptop] ? eeepc_hotk_resume [eeepc_laptop] ? acpi_device_resume ? device_resume ? hibernation_snapshot It appears the PCI device is removed twice. The eeepc_rfkill_hotplug() call from the resume handler is racing against the call from the ACPI notifier callback. The ACPI notification is triggered by the resume handler when it refreshes the value of CM_ASL_WLAN. The fix is to serialize hotplug calls using a workqueue. http://bugzilla.kernel.org/show_bug.cgi?id=13825 Signed-off-by: Alan Jenkins Acked-by: Corentin Chary Signed-off-by: Len Brown --- diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c index ec560f16d72..222ffb892f2 100644 --- a/drivers/platform/x86/eeepc-laptop.c +++ b/drivers/platform/x86/eeepc-laptop.c @@ -143,6 +143,7 @@ struct eeepc_hotk { struct rfkill *bluetooth_rfkill; struct rfkill *wwan3g_rfkill; struct hotplug_slot *hotplug_slot; + struct work_struct hotplug_work; }; /* The actual device the driver binds to */ @@ -660,7 +661,7 @@ static int eeepc_get_adapter_status(struct hotplug_slot *hotplug_slot, return 0; } -static void eeepc_rfkill_hotplug(void) +static void eeepc_hotplug_work(struct work_struct *work) { struct pci_dev *dev; struct pci_bus *bus = pci_find_bus(0, 1); @@ -701,7 +702,7 @@ static void eeepc_rfkill_notify(acpi_handle handle, u32 event, void *data) if (event != ACPI_NOTIFY_BUS_CHECK) return; - eeepc_rfkill_hotplug(); + schedule_work(&ehotk->hotplug_work); } static void eeepc_hotk_notify(struct acpi_device *device, u32 event) @@ -892,7 +893,7 @@ static int eeepc_hotk_resume(struct acpi_device *device) rfkill_set_sw_state(ehotk->wlan_rfkill, wlan != 1); - eeepc_rfkill_hotplug(); + schedule_work(&ehotk->hotplug_work); } if (ehotk->bluetooth_rfkill) @@ -1093,6 +1094,8 @@ static int eeepc_rfkill_init(struct device *dev) { int result = 0; + INIT_WORK(&ehotk->hotplug_work, eeepc_hotplug_work); + eeepc_register_rfkill_notifier("\\_SB.PCI0.P0P6"); eeepc_register_rfkill_notifier("\\_SB.PCI0.P0P7");