From 84544a1dea61879edebceddb7a76d5737409f8c8 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 19 Sep 2012 11:54:15 -0700 Subject: PCI: Fix default vga ref_count when __ARCH_HAS_VGA_DEFAULT_DEVICE is not defined, aka EFIFB is not used, for static path, vga_default setting is through vga_arbiter_add_pci_device. and later x86 pci_fixup_video, will skip setting again. - subsys_initcall(vga_arb_device_init) come first to call vga_arbiter_add_pci_device. It will call pci_get_dev to hold one reference. for hotplug add path, even vga_arbiter_add_pci_device is called via notifier, but it will check VGA_RSRC_LEGACY_MASK that is not set for hotplug path. So x86 pci_fixup_video will take over to call vga_set_default_device(). It will not hold one refrence. Later for hotplug remove path, vga_arbiter_del_pci_device that does not check VGA_RSRC_LEGACY_MASK will call put_device and it will cause ref_count to decrease extra. that will have that pci device get deleted early wrongly. Need to make get/put balance for both cases. Signed-off-by: Yinghai Lu Signed-off-by: Bjorn Helgaas Cc: x86@kernel.org Cc: Dave Airlie Cc: Andrew Morton Cc: Julia Lawall Cc: Matthew Garrett --- drivers/gpu/vga/vgaarb.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c index 3df8fc0ec01a..7a439b84dd42 100644 --- a/drivers/gpu/vga/vgaarb.c +++ b/drivers/gpu/vga/vgaarb.c @@ -141,7 +141,11 @@ EXPORT_SYMBOL_GPL(vga_default_device); void vga_set_default_device(struct pci_dev *pdev) { - vga_default = pdev; + if (vga_default == pdev) + return; + + pci_dev_put(vga_default); + vga_default = pci_dev_get(pdev); } #endif @@ -577,7 +581,7 @@ static bool vga_arbiter_add_pci_device(struct pci_dev *pdev) #ifndef __ARCH_HAS_VGA_DEFAULT_DEVICE if (vga_default == NULL && ((vgadev->owns & VGA_RSRC_LEGACY_MASK) == VGA_RSRC_LEGACY_MASK)) - vga_default = pci_dev_get(pdev); + vga_set_default_device(pdev); #endif vga_arbiter_check_bridge_sharing(vgadev); @@ -613,10 +617,8 @@ static bool vga_arbiter_del_pci_device(struct pci_dev *pdev) } #ifndef __ARCH_HAS_VGA_DEFAULT_DEVICE - if (vga_default == pdev) { - pci_dev_put(vga_default); - vga_default = NULL; - } + if (vga_default == pdev) + vga_set_default_device(NULL); #endif if (vgadev->decodes & (VGA_RSRC_LEGACY_IO | VGA_RSRC_LEGACY_MEM)) -- cgit v1.2.3