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  1. Bug #1836858
  2. Comment #36

Comment 36 for bug 1836858

Revision history for this message
Basic (basicxp) wrote (last edit ):

Affects me as well. Reproduced on:

* Dell XPS 7390, i7-10510U, integrated graphics, laptop screen
* Focal with latest updates
* Kernels:
  * 5.8.0-55-generic (linux-image-generic-hwe-20.04)
  * 5.13.0-rc4 (vanilla from kernel-ppa/mainline)

In the kernel log, "fb0: switching to inteldrmfb from EFI VGA" is the last line I see before the mode change, and "clocksource: tsc: mask: 0xffffffffffffffff..." is the first line once the screen turns back on.

i915.fastboot=1 is set in kernel cmdline, didn't make any difference. Resolution is visually the same before and after the mode change.

Same behaviour if I disable "splash" and/or "quiet". Using full disk encryption, if it matters.

---

[ 1.202214] fb0: switching to inteldrmfb from EFI VGA
[ 1.204981] Console: switching to colour dummy device 80x25
[ 1.205002] i915 0000:00:02.0: vgaarb: deactivate vga console
[ 1.257470] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[ 1.257523] i915 0000:00:02.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=io+mem:owns=io+mem
[ 1.258039] i915 0000:00:02.0: [drm] Finished loading DMC firmware i915/kbl_dmc_ver1_04.bin (v1.4)
[ 1.266513] i915 0000:00:02.0: [drm] Panel advertises DPCD backlight support, but VBT disagrees. If your backlight controls don't work try booting with i915.enable_dpcd_backlight=1. If your machine needs this, please file a _new_ bug report on drm/i915, see https://gitlab.freedesktop.org/drm/intel/-/wikis/How-to-file-i915-bugs for details.
[ 1.278853] [drm] Initialized i915 1.6.0 20200515 for 0000:00:02.0 on minor 0
[ 1.388057] usb 1-9: new high-speed USB device number 2 using xhci_hcd
[ 1.528528] usb 4-1: new SuperSpeed Gen 1 USB device number 2 using xhci_hcd
[ 1.543379] usb 1-9: New USB device found, idVendor=2109, idProduct=2812, bcdDevice= d.a0
[ 1.543392] usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 1.543399] usb 1-9: Product: USB2.0 Hub
[ 1.543404] usb 1-9: Manufacturer: VIA Labs, Inc.
[ 1.544575] hub 1-9:1.0: USB hub found
[ 1.545569] hub 1-9:1.0: 4 ports detected
[ 1.564060] tsc: Refined TSC clocksource calibration: 2303.993 MHz
[ 1.564082] clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x2135f10e1ea, max_idle_ns: 440795202126 ns