Commits
Toshi Kani committed 8fcfb99c8e2
ACPI / hotplug: Fix panic on eject to ejected device When an eject request is sent to an ejected ACPI device, the following panic occurs: ACPI: \_SB_.SCK3.CPU3: ACPI_NOTIFY_EJECT_REQUEST event BUG: unable to handle kernel NULL pointer dereference at 0000000000000070 IP: [<ffffffff813a7cfe>] acpi_device_hotplug+0x10b/0x33b : Call Trace: [<ffffffff813a24da>] acpi_hotplug_work_fn+0x1c/0x27 [<ffffffff8109cbe5>] process_one_work+0x175/0x430 [<ffffffff8109d7db>] worker_thread+0x11b/0x3a0 This is becase device->handler is NULL in acpi_device_hotplug(). This case was used to fail in acpi_hotplug_notify_cb() as the target had no acpi_deivce. However, acpi_device now exists after ejection. Added a check to verify if acpi_device->handler is valid for an eject request in acpi_hotplug_notify_cb(). Note that handler passed from an argument is still valid while acpi_device->handler is NULL. Fixes: 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace) Signed-off-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>