Acabo de realizar una nueva instalación de kubuntu 20.04 en un nuevo thinkpad 495s.
La pantalla de inicio de sesión (gráfica) parece normal, excepto que falta el puntero del mouse. Sin embargo, después de iniciar sesión, tengo una pantalla mayoritariamente negra/grisácea. Al iniciar una consola (usando ctrl-alt-t), puedo adivinar por el gris que está allí, solo para poder escribir sudo shutdown now.
Sin embargo, si inicio usando el modo de recuperación, la computadora es casi utilizable, excepto que no puedo controlar la luz de fondo de la pantalla: al presionar fn-F5aparece la ventana de control de luz de fondo que muestra que se debe disminuir la luz de fondo, pero en realidad no sucede nada.
EDITAR: aparentemente, tanto la pantalla como la luz de fondo funcionan si inicio con la alimentación enchufada.
No sé si estos dos problemas están relacionados entre sí.
martin@toolbox:~$ uname -r
5.4.0-45-generic
martin@toolbox:~$ lspci
00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Root Complex
00:00.2 IOMMU: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 IOMMU
00:01.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge
00:01.2 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.3 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:01.7 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 PCIe GPP Bridge [6:0]
00:08.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 00h-1fh) PCIe Dummy Host Bridge
00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Internal PCIe GPP Bridge 0 to Bus A
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 61)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 51)
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 0
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 5
00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 6
00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Raven/Raven2 Device 24: Function 7
01:00.0 Network controller: Intel Corporation Wireless-AC 9260 (rev 29)
02:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller SM981/PM981/PM983
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 0e)
03:00.1 Serial controller: Realtek Semiconductor Co., Ltd. Device 816a (rev 0e)
03:00.2 Serial controller: Realtek Semiconductor Co., Ltd. Device 816b (rev 0e)
03:00.3 IPMI Interface: Realtek Semiconductor Co., Ltd. Device 816c (rev 0e)
03:00.4 USB controller: Realtek Semiconductor Co., Ltd. Device 816d (rev 0e)
04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS522A PCI Express Card Reader (rev 01)
05:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Picasso (rev d2)
05:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Raven/Raven2/Fenghuang HDMI/DP Audio Controller
05:00.2 Encryption controller: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 10h-1fh) Platform Security Processor
05:00.3 USB controller: Advanced Micro Devices, Inc. [AMD] Raven USB 3.1
05:00.4 USB controller: Advanced Micro Devices, Inc. [AMD] Raven USB 3.1
05:00.5 Multimedia controller: Advanced Micro Devices, Inc. [AMD] Raven/Raven2/FireFlight/Renoir Audio Processor
05:00.6 Audio device: Advanced Micro Devices, Inc. [AMD] Family 17h (Models 10h-1fh) HD Audio Controller
Respuesta1
¿Has probado la opción de arranque "iommu=soft" como se describe aquí?
https://www.reddit.com/r/thinkpad/comments/eb08hk/t495_unplugged_battery_broken_boot_with_linux/
Quizás esto también resuelva tu problema...