]> git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/commit
ACPI / hotplug: Fix panic on eject to ejected device
authorToshi Kani <toshi.kani@hp.com>
Wed, 5 Feb 2014 00:48:28 +0000 (17:48 -0700)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Wed, 5 Feb 2014 11:14:43 +0000 (12:14 +0100)
commit8fcfb99c8e29c73dd8945b6105ef54ca4eeb171e
tree76c00d699fc74a9fd31e3c5508799d42c169256a
parent38dbfb59d1175ef458d006556061adeaa8751b72
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>
drivers/acpi/scan.c