Re: [PATCH 6.0 20/20] fbdev/core: Remove remove_conflicting_pci_framebuffers()
From: Boris V.
Date: Tue Nov 01 2022 - 04:48:35 EST
On 24/10/2022 13:31, Greg Kroah-Hartman wrote:
From: Thomas Zimmermann <tzimmermann@xxxxxxx>
commit 9d69ef1838150c7d87afc1a87aa658c637217585 upstream.
Remove remove_conflicting_pci_framebuffers() and implement similar
functionality in aperture_remove_conflicting_pci_device(), which was
the only caller. Removes an otherwise unused interface and streamlines
the aperture helper. No functional changes.
Signed-off-by: Thomas Zimmermann <tzimmermann@xxxxxxx>
Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20220718072322.8927-5-tzimmermann@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/video/aperture.c | 30 ++++++++++++++----------
drivers/video/fbdev/core/fbmem.c | 48 ---------------------------------------
include/linux/fb.h | 2 -
3 files changed, 18 insertions(+), 62 deletions(-)
--- a/drivers/video/aperture.c
+++ b/drivers/video/aperture.c
@@ -335,30 +335,36 @@ EXPORT_SYMBOL(aperture_remove_conflictin
*/
int aperture_remove_conflicting_pci_devices(struct pci_dev *pdev, const char *name)
{
+ bool primary = false;
resource_size_t base, size;
int bar, ret;
- /*
- * WARNING: Apparently we must kick fbdev drivers before vgacon,
- * otherwise the vga fbdev driver falls over.
- */
-#if IS_REACHABLE(CONFIG_FB)
- ret = remove_conflicting_pci_framebuffers(pdev, name);
- if (ret)
- return ret;
+#ifdef CONFIG_X86
+ primary = pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW;
#endif
- ret = vga_remove_vgacon(pdev);
- if (ret)
- return ret;
for (bar = 0; bar < PCI_STD_NUM_BARS; ++bar) {
if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
continue;
+
base = pci_resource_start(pdev, bar);
size = pci_resource_len(pdev, bar);
- aperture_detach_devices(base, size);
+ ret = aperture_remove_conflicting_devices(base, size, primary, name);
+ if (ret)
+ break;
}
+ if (ret)
+ return ret;
+
+ /*
+ * WARNING: Apparently we must kick fbdev drivers before vgacon,
+ * otherwise the vga fbdev driver falls over.
+ */
+ ret = vga_remove_vgacon(pdev);
+ if (ret)
+ return ret;
+
return 0;
}
--- a/drivers/video/fbdev/core/fbmem.c
+++ b/drivers/video/fbdev/core/fbmem.c
@@ -1788,54 +1788,6 @@ int remove_conflicting_framebuffers(stru
EXPORT_SYMBOL(remove_conflicting_framebuffers);
/**
- * remove_conflicting_pci_framebuffers - remove firmware-configured framebuffers for PCI devices
- * @pdev: PCI device
- * @name: requesting driver name
- *
- * This function removes framebuffer devices (eg. initialized by firmware)
- * using memory range configured for any of @pdev's memory bars.
- *
- * The function assumes that PCI device with shadowed ROM drives a primary
- * display and so kicks out vga16fb.
- */
-int remove_conflicting_pci_framebuffers(struct pci_dev *pdev, const char *name)
-{
- struct apertures_struct *ap;
- bool primary = false;
- int err, idx, bar;
-
- for (idx = 0, bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
- if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
- continue;
- idx++;
- }
-
- ap = alloc_apertures(idx);
- if (!ap)
- return -ENOMEM;
-
- for (idx = 0, bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
- if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM))
- continue;
- ap->ranges[idx].base = pci_resource_start(pdev, bar);
- ap->ranges[idx].size = pci_resource_len(pdev, bar);
- pci_dbg(pdev, "%s: bar %d: 0x%lx -> 0x%lx\n", __func__, bar,
- (unsigned long)pci_resource_start(pdev, bar),
- (unsigned long)pci_resource_end(pdev, bar));
- idx++;
- }
-
-#ifdef CONFIG_X86
- primary = pdev->resource[PCI_ROM_RESOURCE].flags &
- IORESOURCE_ROM_SHADOW;
-#endif
- err = remove_conflicting_framebuffers(ap, name, primary);
- kfree(ap);
- return err;
-}
-EXPORT_SYMBOL(remove_conflicting_pci_framebuffers);
-
-/**
* register_framebuffer - registers a frame buffer device
* @fb_info: frame buffer info structure
*
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -615,8 +615,6 @@ extern ssize_t fb_sys_write(struct fb_in
/* drivers/video/fbmem.c */
extern int register_framebuffer(struct fb_info *fb_info);
extern void unregister_framebuffer(struct fb_info *fb_info);
-extern int remove_conflicting_pci_framebuffers(struct pci_dev *pdev,
- const char *name);
extern int remove_conflicting_framebuffers(struct apertures_struct *a,
const char *name, bool primary);
extern int fb_prepare_logo(struct fb_info *fb_info, int rotate);
Hello,
this patch seems to disable console/framebuffer when vfio-pci is used.
I hava 2 nvidia GPUs one is used for host and other is passed through to VM.
Now after this patch, when vfio-pci module is loaded with parameter
ids=10de:2486,10de:228b,
console is lost/frozen, last message is that vfio-pci module was loaded
and then there is no more output.
This PCI IDs (10de:2486,10de:228b) are for secondary GPU, primary/boot
GPU is used for host and boot messages are displayed on primary/boot GPU.
Using dmesg I see this messages after vfio-pci is loaded:
[ 3.993601] VFIO - User Level meta-driver version: 0.3
[ 4.020239] Console: switching to colour dummy device 80x25
[ 4.020335] vfio-pci 0000:1a:00.0: vgaarb: changed VGA decodes:
olddecodes=io+mem,decodes=none:owns=none
[ 4.020722] vfio_pci: add [10de:2486[ffffffff:ffffffff]] class
0x000000/00000000
[ 4.116616] vfio_pci: add [10de:228b[ffffffff:ffffffff]] class
0x000000/00000000
I guess the problem here is "Console: switching to colour dummy device
80x25", but I don't know why this happens.
Last working kernel is 6.0.3, after upgrading to 6.0.4 (and 6.0.5,
6.0.6), console is no longer working.
By git bisecting it seems bad commit is
af9ac541e88390d97b01d5e8c77309d2637c1d4c.