From b64c115eb22516ecd187c74ad6de3f1693f1dc7b Mon Sep 17 00:00:00 2001 From: Dave Airlie Date: Tue, 14 Sep 2010 20:14:38 +1000 Subject: [PATCH] drm: fix race between driver loading and userspace open. Not 100% sure this is due to BKL removal, its most likely a combination of that + userspace timing changes in udev/plymouth. The drm adds the sysfs device before the driver has completed internal loading, this causes udev to make the node and plymouth to open it before we've completed loading. The proper solution is to delay the sysfs manipulation until later in loading however this causes knock on issues with sysfs connector nodes, so we can use the global mutex to serialise loading and userspace opens. Reported-by: Toni Spets (hifi on #radeon) Signed-off-by: Dave Airlie --- drivers/gpu/drm/drm_pci.c | 4 ++++ drivers/gpu/drm/drm_platform.c | 5 +++++ 2 files changed, 9 insertions(+) diff --git a/drivers/gpu/drm/drm_pci.c b/drivers/gpu/drm/drm_pci.c index e20f78b542a7..f5bd9e590c80 100644 --- a/drivers/gpu/drm/drm_pci.c +++ b/drivers/gpu/drm/drm_pci.c @@ -164,6 +164,8 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent, dev->hose = pdev->sysdata; #endif + mutex_lock(&drm_global_mutex); + if ((ret = drm_fill_in_dev(dev, ent, driver))) { printk(KERN_ERR "DRM: Fill_in_dev failed.\n"); goto err_g2; @@ -199,6 +201,7 @@ int drm_get_pci_dev(struct pci_dev *pdev, const struct pci_device_id *ent, driver->name, driver->major, driver->minor, driver->patchlevel, driver->date, pci_name(pdev), dev->primary->index); + mutex_unlock(&drm_global_mutex); return 0; err_g4: @@ -210,6 +213,7 @@ err_g2: pci_disable_device(pdev); err_g1: kfree(dev); + mutex_unlock(&drm_global_mutex); return ret; } EXPORT_SYMBOL(drm_get_pci_dev); diff --git a/drivers/gpu/drm/drm_platform.c b/drivers/gpu/drm/drm_platform.c index 460e9a3afa8d..92d1d0fb7b75 100644 --- a/drivers/gpu/drm/drm_platform.c +++ b/drivers/gpu/drm/drm_platform.c @@ -53,6 +53,8 @@ int drm_get_platform_dev(struct platform_device *platdev, dev->platformdev = platdev; dev->dev = &platdev->dev; + mutex_lock(&drm_global_mutex); + ret = drm_fill_in_dev(dev, NULL, driver); if (ret) { @@ -87,6 +89,8 @@ int drm_get_platform_dev(struct platform_device *platdev, list_add_tail(&dev->driver_item, &driver->device_list); + mutex_unlock(&drm_global_mutex); + DRM_INFO("Initialized %s %d.%d.%d %s on minor %d\n", driver->name, driver->major, driver->minor, driver->patchlevel, driver->date, dev->primary->index); @@ -100,6 +104,7 @@ err_g2: drm_put_minor(&dev->control); err_g1: kfree(dev); + mutex_unlock(&drm_global_mutex); return ret; } EXPORT_SYMBOL(drm_get_platform_dev); -- 2.30.2