3.0-stable review patch. If anyone has any objections, please let me know.
------------------ From: Kay Sievers <[email protected]> commit ce880cb860f36694d2cdebfac9e6ae18176fe4c4 upstream. The USB graphics card driver delays the unregistering of the framebuffer device to a workqueue, which breaks the userspace visible remove uevent sequence. Recent userspace tools started to support USB graphics card hotplug out-of-the-box and rely on proper events sent by the kernel. The framebuffer device is a direct child of the USB interface which is removed immediately after the USB .disconnect() callback. But the fb device in /sys stays around until its final cleanup, at a time where all the parent devices have been removed already. To work around that, we remove the sysfs fb device directly in the USB .disconnect() callback and leave only the cleanup of the internal fb data to the delayed work. Before: add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/graphics/fb0 (graphics) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) remove /2-1.2:1.0/graphics/fb0 (graphics) After: add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) add /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/graphics/fb1 (graphics) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0/graphics/fb1 (graphics) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2/2-1.2:1.0 (usb) remove /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.2 (usb) Tested-by: Bernie Thompson <[email protected]> Acked-by: Bernie Thompson <[email protected]> Signed-off-by: Kay Sievers <[email protected]> Signed-off-by: Florian Tobias Schandinat <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/video/fbmem.c | 18 +++++++++++++++++- drivers/video/udlfb.c | 2 +- include/linux/fb.h | 1 + 3 files changed, 19 insertions(+), 2 deletions(-) --- a/drivers/video/fbmem.c +++ b/drivers/video/fbmem.c @@ -1651,6 +1651,7 @@ static int do_unregister_framebuffer(str if (ret) return -EINVAL; + unlink_framebuffer(fb_info); if (fb_info->pixmap.addr && (fb_info->pixmap.flags & FB_PIXMAP_DEFAULT)) kfree(fb_info->pixmap.addr); @@ -1658,7 +1659,6 @@ static int do_unregister_framebuffer(str registered_fb[i] = NULL; num_registered_fb--; fb_cleanup_device(fb_info); - device_destroy(fb_class, MKDEV(FB_MAJOR, i)); event.info = fb_info; fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event); @@ -1667,6 +1667,22 @@ static int do_unregister_framebuffer(str return 0; } +int unlink_framebuffer(struct fb_info *fb_info) +{ + int i; + + i = fb_info->node; + if (i < 0 || i >= FB_MAX || registered_fb[i] != fb_info) + return -EINVAL; + + if (fb_info->dev) { + device_destroy(fb_class, MKDEV(FB_MAJOR, i)); + fb_info->dev = NULL; + } + return 0; +} +EXPORT_SYMBOL(unlink_framebuffer); + void remove_conflicting_framebuffers(struct apertures_struct *a, const char *name, bool primary) { --- a/drivers/video/udlfb.c +++ b/drivers/video/udlfb.c @@ -1666,7 +1666,7 @@ static void dlfb_usb_disconnect(struct u for (i = 0; i < ARRAY_SIZE(fb_device_attrs); i++) device_remove_file(info->dev, &fb_device_attrs[i]); device_remove_bin_file(info->dev, &edid_attr); - + unlink_framebuffer(info); usb_set_intfdata(interface, NULL); /* if clients still have us open, will be freed on last close */ --- a/include/linux/fb.h +++ b/include/linux/fb.h @@ -997,6 +997,7 @@ extern ssize_t fb_sys_write(struct fb_in /* drivers/video/fbmem.c */ extern int register_framebuffer(struct fb_info *fb_info); extern int unregister_framebuffer(struct fb_info *fb_info); +extern int unlink_framebuffer(struct fb_info *fb_info); extern void remove_conflicting_framebuffers(struct apertures_struct *a, const char *name, bool primary); extern int fb_prepare_logo(struct fb_info *fb_info, int rotate); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
