# # README for usbip-utils # # Copyright (C) 2011 matt mooney # 2005-2008 Takahiro Hirofuchi [Requirements] - USB/IP device drivers Found in the staging directory of the Linux kernel. - libudev >= 2.0 libudev library - libwrap0-dev tcp wrapper library - gcc >= 4.0 - libtool, automake >= 1.9, autoconf >= 2.5.0, pkg-config [Optional] - hwdata Contains USB device identification data. [Install] 0. Generate configuration scripts. $ ./autogen.sh 1. Compile & install the userspace utilities. $ ./configure [--with-tcp-wrappers=no] [--with-usbids-dir=] $ make install 2. Compile & install USB/IP drivers. [Usage] server:# (Physically attach your USB device.) server:# insmod usbip-core.ko server:# insmod usbip-host.ko server:# usbipd -D - Start usbip daemon. server:# usbip list -l - List driver assignments for USB devices. server:# usbip bind --busid 1-2 - Bind usbip-host.ko to the device with busid 1-2. - The USB device 1-2 is now exportable to other hosts! - Use `usbip unbind --busid 1-2' to stop exporting the device. client:# insmod usbip-core.ko client:# insmod vhci-hcd.ko client:# usbip list --remote - List exported USB devices on the . client:# usbip attach --remote --busid 1-2 - Connect the remote USB device. client:# usbip port - Show virtual port status. client:# usbip detach --port - Detach the USB device. [Example] --------------------------- SERVER SIDE --------------------------- Physically attach your USB devices to this host. trois:# insmod path/to/usbip-core.ko trois:# insmod path/to/usbip-host.ko trois:# usbipd -D In another terminal, let's look up what USB devices are physically attached to this host. trois:# usbip list -l Local USB devices ================= - busid 1-1 (05a9:a511) 1-1:1.0 -> ov511 - busid 3-2 (0711:0902) 3-2:1.0 -> none - busid 3-3.1 (08bb:2702) 3-3.1:1.0 -> snd-usb-audio 3-3.1:1.1 -> snd-usb-audio - busid 3-3.2 (04bb:0206) 3-3.2:1.0 -> usb-storage - busid 3-3 (0409:0058) 3-3:1.0 -> hub - busid 4-1 (046d:08b2) 4-1:1.0 -> none 4-1:1.1 -> none 4-1:1.2 -> none - busid 5-2 (058f:9254) 5-2:1.0 -> hub A USB storage device of busid 3-3.2 is now bound to the usb-storage driver. To export this device, we first mark the device as "exportable"; the device is bound to the usbip-host driver. Please remember you can not export a USB hub. Mark the device of busid 3-3.2 as exportable: trois:# usbip --debug bind --busid 3-3.2 ... usbip debug: usbip_bind.c:162:[unbind_other] 3-3.2:1.0 -> usb-storage ... bind device on busid 3-3.2: complete trois:# usbip list -l Local USB devices ================= ... - busid 3-3.2 (04bb:0206) 3-3.2:1.0 -> usbip-host ... --------------------------- CLIENT SIDE --------------------------- First, let's list available remote devices that are marked as exportable on the host. deux:# insmod path/to/usbip-core.ko deux:# insmod path/to/vhci-hcd.ko deux:# usbip list --remote 10.0.0.3 Exportable USB devices ====================== - 10.0.0.3 1-1: Prolific Technology, Inc. : unknown product (067b:3507) : /sys/devices/pci0000:00/0000:00:1f.2/usb1/1-1 : (Defined at Interface level) / unknown subclass / unknown protocol (00/00/00) : 0 - Mass Storage / SCSI / Bulk (Zip) (08/06/50) 1-2.2.1: Apple Computer, Inc. : unknown product (05ac:0203) : /sys/devices/pci0000:00/0000:00:1f.2/usb1/1-2/1-2.2/1-2.2.1 : (Defined at Interface level) / unknown subclass / unknown protocol (00/00/00) : 0 - Human Interface Devices / Boot Interface Subclass / Keyboard (03/01/01) 1-2.2.3: OmniVision Technologies, Inc. : OV511+ WebCam (05a9:a511) : /sys/devices/pci0000:00/0000:00:1f.2/usb1/1-2/1-2.2/1-2.2.3 : (Defined at Interface level) / unknown subclass / unknown protocol (00/00/00) : 0 - Vendor Specific Class / unknown subclass / unknown protocol (ff/00/00) 3-1: Logitech, Inc. : QuickCam Pro 4000 (046d:08b2) : /sys/devices/pci0000:00/0000:00:1e.0/0000:02:0a.0/usb3/3-1 : (Defined at Interface level) / unknown subclass / unknown protocol (00/00/00) : 0 - Data / unknown subclass / unknown protocol (0a/ff/00) : 1 - Audio / Control Device / unknown protocol (01/01/00) : 2 - Audio / Streaming / unknown protocol (01/02/00) Attach a remote USB device: deux:# usbip attach --remote 10.0.0.3 --busid 1-1 port 0 attached Show the devices attached to this client: deux:# usbip port Port 00: at Full Speed(12Mbps) Prolific Technology, Inc. : unknown product (067b:3507) 6-1 -> usbip://10.0.0.3:3240/1-1 (remote bus/dev 001/004) 6-1:1.0 used by usb-storage /sys/class/scsi_device/0:0:0:0/device /sys/class/scsi_host/host0/device /sys/block/sda/device Detach the imported device: deux:# usbip detach --port 0 port 0 detached [Checklist] - See 'Debug Tips' on the project wiki. - http://usbip.wiki.sourceforge.net/how-to-debug-usbip - usbip-host.ko must be bound to the target device. - See /proc/bus/usb/devices and find "Driver=..." lines of the device. - Shutdown firewall. - usbip now uses TCP port 3240. - Disable SELinux. - Check the kernel and daemon messages. [Contact] Mailing List: linux-usb@vger.kernel.org cb2c9a316e77f6dfba96c543e55b6672d5a37e'>drivers/usb/musb/musb_virthub.c parent2c5d9555d6d937966d79d4c6529a5f7b9206e405 (diff)
drm/i915: Check for NULL i915_vma in intel_unpin_fb_obj()
I've seen this trigger twice now, where the i915_gem_object_to_ggtt() call in intel_unpin_fb_obj() returns NULL, resulting in an oops immediately afterwards as the (inlined) call to i915_vma_unpin_fence() tries to dereference it. It seems to be some race condition where the object is going away at shutdown time, since both times happened when shutting down the X server. The call chains were different: - VT ioctl(KDSETMODE, KD_TEXT): intel_cleanup_plane_fb+0x5b/0xa0 [i915] drm_atomic_helper_cleanup_planes+0x6f/0x90 [drm_kms_helper] intel_atomic_commit_tail+0x749/0xfe0 [i915] intel_atomic_commit+0x3cb/0x4f0 [i915] drm_atomic_commit+0x4b/0x50 [drm] restore_fbdev_mode+0x14c/0x2a0 [drm_kms_helper] drm_fb_helper_restore_fbdev_mode_unlocked+0x34/0x80 [drm_kms_helper] drm_fb_helper_set_par+0x2d/0x60 [drm_kms_helper] intel_fbdev_set_par+0x18/0x70 [i915] fb_set_var+0x236/0x460 fbcon_blank+0x30f/0x350 do_unblank_screen+0xd2/0x1a0 vt_ioctl+0x507/0x12a0 tty_ioctl+0x355/0xc30 do_vfs_ioctl+0xa3/0x5e0 SyS_ioctl+0x79/0x90 entry_SYSCALL_64_fastpath+0x13/0x94 - i915 unpin_work workqueue: intel_unpin_work_fn+0x58/0x140 [i915] process_one_work+0x1f1/0x480 worker_thread+0x48/0x4d0 kthread+0x101/0x140 and this patch purely papers over the issue by adding a NULL pointer check and a WARN_ON_ONCE() to avoid the oops that would then generally make the machine unresponsive. Other callers of i915_gem_object_to_ggtt() seem to also check for the returned pointer being NULL and warn about it, so this clearly has happened before in other places. [ Reported it originally to the i915 developers on Jan 8, applying the ugly workaround on my own now after triggering the problem for the second time with no feedback. This is likely to be the same bug reported as https://bugs.freedesktop.org/show_bug.cgi?id=98829 https://bugs.freedesktop.org/show_bug.cgi?id=99134 which has a patch for the underlying problem, but it hasn't gotten to me, so I'm applying the workaround. ] Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/usb/musb/musb_virthub.c')