Activity log for bug #1807140

Date Who What changed Old value New value Message
2018-12-06 13:08:24 Dmitrii Shcherbakov bug added bug
2018-12-06 13:19:31 Dmitrii Shcherbakov description I ran into a problem with the console argument handling on a physical system with a BMC (Dell R610) and also reproduced the same behavior on a QEMU/KVM VM with multiple serial ports. The kernel documentation notes that the last entry will https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-tty "What: /sys/class/tty/console/active Shows the list of currently configured console devices, like 'tty1 ttyS0'. The last entry in the file is the active device connected to /dev/console. The file supports poll() to detect virtual console switches." https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1960 "The last preferred console added will be used for kernel messages and stdin/out/err for init." The actual behavior is different and the console specified in the last console argument does not become an active one. As a result, SOL functionality is not possible to use unless only one ttyS<n> argument is specified in the kernel command line arguments. Setting the arguments to only contain the right one results in a proper behavior and I can see rx counters increasing in /proc/tty/driver/serial for the relevant port after I type something via the BMC. $ cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 journalctl -k | grep ttyS Dec 03 21:42:41 ubuntu kernel: Command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: Kernel command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: console [ttyS0] enabled Dec 03 21:42:41 ubuntu kernel: 00:02: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: 00:03: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: tty ttyS3: hash matches Full dmesg: http://paste.ubuntu.com/p/bV2pDc4Hdw/ $ cat /sys/class/tty/console/active ttyS0 tty0 $ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:78 rx:0 RTS|DTR 1: uart:16550A port:000002F8 irq:3 tx:0 rx:0 CTS|DSR|CD 2: uart:unknown port:000003E8 irq:4 3: uart:unknown port:000002E8 irq:3 # ... ~~~ GRUB setttings: # the ones that override /etc/default/grub $ cat /etc/default/grub.d/50-curtin-settings.cfg cat: cat: No such file or directory GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,115200 console=ttyS1,115200" # disable grub os prober that might find other OS installs. GRUB_DISABLE_OS_PROBER=true GRUB_TERMINAL=console /etc/default/grub: https://paste.ubuntu.com/p/sdWQrY7JwN/ # grub.cfg: http://paste.ubuntu.com/p/zKGTqDh6sR/ # two entries, both with the proper arg and properly sent to the kernel cmdline based on /proc/cmdline grep ttyS grub.cfg linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 ~~~ I managed to reproduce the exact same behavior on a VM with multiple 8250 serial ports. ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS0 ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 # changed to the following config with only ttyS1 present: ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # 1 tty passed only ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # now it's shown as active ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS1 ubuntu@maas-vhost5:~$ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:0 rx:0 CTS|DSR|CD 1: uart:16550A port:000002F8 irq:3 tx:14763 rx:0 RTS|CTS|DTR|DSR|CD 2: uart:16550A port:000003E8 irq:4 tx:0 rx:0 CTS|DSR|CD ~~~~ Relevant code: https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L2379 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1916 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1961 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1886 I ran into a problem with the console argument handling on a physical system with a BMC (Dell R610) and also reproduced the same behavior on a QEMU/KVM VM with multiple serial ports. The kernel documentation notes that the last entry will be used for /dev/console https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-tty "What: /sys/class/tty/console/active          Shows the list of currently configured console devices, like 'tty1 ttyS0'. The last entry in the file is the active device connected to /dev/console.          The file supports poll() to detect virtual console switches." https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1960 "The last preferred console added will be used for kernel messages and stdin/out/err for init." The actual behavior is different and the console specified in the last console argument does not become an active one. As a result, SOL functionality is not possible to use unless only one ttyS<n> argument is specified in the kernel command line arguments. Setting the arguments to only contain the right one results in a proper behavior and I can see rx counters increasing in /proc/tty/driver/serial for the relevant port after I type something via the BMC. $ cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 journalctl -k | grep ttyS Dec 03 21:42:41 ubuntu kernel: Command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: Kernel command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: console [ttyS0] enabled Dec 03 21:42:41 ubuntu kernel: 00:02: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: 00:03: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: tty ttyS3: hash matches Full dmesg: http://paste.ubuntu.com/p/bV2pDc4Hdw/ $ cat /sys/class/tty/console/active ttyS0 tty0 $ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:78 rx:0 RTS|DTR 1: uart:16550A port:000002F8 irq:3 tx:0 rx:0 CTS|DSR|CD 2: uart:unknown port:000003E8 irq:4 3: uart:unknown port:000002E8 irq:3 # ... ~~~ GRUB setttings: # the ones that override /etc/default/grub $ cat /etc/default/grub.d/50-curtin-settings.cfg cat: cat: No such file or directory GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,115200 console=ttyS1,115200" # disable grub os prober that might find other OS installs. GRUB_DISABLE_OS_PROBER=true GRUB_TERMINAL=console /etc/default/grub: https://paste.ubuntu.com/p/sdWQrY7JwN/ # grub.cfg: http://paste.ubuntu.com/p/zKGTqDh6sR/ # two entries, both with the proper arg and properly sent to the kernel cmdline based on /proc/cmdline grep ttyS grub.cfg         linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200          linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 ~~~ I managed to reproduce the exact same behavior on a VM with multiple 8250 serial ports. ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS0 ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg         linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 # changed to the following config with only ttyS1 present: ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg         linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # 1 tty passed only ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # now it's shown as active ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS1 ubuntu@maas-vhost5:~$ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:0 rx:0 CTS|DSR|CD 1: uart:16550A port:000002F8 irq:3 tx:14763 rx:0 RTS|CTS|DTR|DSR|CD 2: uart:16550A port:000003E8 irq:4 tx:0 rx:0 CTS|DSR|CD ~~~~ Relevant code: https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L2379 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1916 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1961 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1886
2018-12-06 13:30:06 Ubuntu Kernel Bot linux (Ubuntu): status New Incomplete
2018-12-06 13:30:07 Ubuntu Kernel Bot tags cpe-onsite bionic cpe-onsite
2018-12-06 14:45:23 Dmitrii Shcherbakov tags bionic cpe-onsite apport-collected bionic cpe-onsite uec-images
2018-12-06 14:45:24 Dmitrii Shcherbakov description I ran into a problem with the console argument handling on a physical system with a BMC (Dell R610) and also reproduced the same behavior on a QEMU/KVM VM with multiple serial ports. The kernel documentation notes that the last entry will be used for /dev/console https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-tty "What: /sys/class/tty/console/active          Shows the list of currently configured console devices, like 'tty1 ttyS0'. The last entry in the file is the active device connected to /dev/console.          The file supports poll() to detect virtual console switches." https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1960 "The last preferred console added will be used for kernel messages and stdin/out/err for init." The actual behavior is different and the console specified in the last console argument does not become an active one. As a result, SOL functionality is not possible to use unless only one ttyS<n> argument is specified in the kernel command line arguments. Setting the arguments to only contain the right one results in a proper behavior and I can see rx counters increasing in /proc/tty/driver/serial for the relevant port after I type something via the BMC. $ cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 journalctl -k | grep ttyS Dec 03 21:42:41 ubuntu kernel: Command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: Kernel command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: console [ttyS0] enabled Dec 03 21:42:41 ubuntu kernel: 00:02: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: 00:03: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: tty ttyS3: hash matches Full dmesg: http://paste.ubuntu.com/p/bV2pDc4Hdw/ $ cat /sys/class/tty/console/active ttyS0 tty0 $ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:78 rx:0 RTS|DTR 1: uart:16550A port:000002F8 irq:3 tx:0 rx:0 CTS|DSR|CD 2: uart:unknown port:000003E8 irq:4 3: uart:unknown port:000002E8 irq:3 # ... ~~~ GRUB setttings: # the ones that override /etc/default/grub $ cat /etc/default/grub.d/50-curtin-settings.cfg cat: cat: No such file or directory GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,115200 console=ttyS1,115200" # disable grub os prober that might find other OS installs. GRUB_DISABLE_OS_PROBER=true GRUB_TERMINAL=console /etc/default/grub: https://paste.ubuntu.com/p/sdWQrY7JwN/ # grub.cfg: http://paste.ubuntu.com/p/zKGTqDh6sR/ # two entries, both with the proper arg and properly sent to the kernel cmdline based on /proc/cmdline grep ttyS grub.cfg         linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200          linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 ~~~ I managed to reproduce the exact same behavior on a VM with multiple 8250 serial ports. ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS0 ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg         linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 # changed to the following config with only ttyS1 present: ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg         linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # 1 tty passed only ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # now it's shown as active ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS1 ubuntu@maas-vhost5:~$ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:0 rx:0 CTS|DSR|CD 1: uart:16550A port:000002F8 irq:3 tx:14763 rx:0 RTS|CTS|DTR|DSR|CD 2: uart:16550A port:000003E8 irq:4 tx:0 rx:0 CTS|DSR|CD ~~~~ Relevant code: https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L2379 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1916 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1961 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1886 I ran into a problem with the console argument handling on a physical system with a BMC (Dell R610) and also reproduced the same behavior on a QEMU/KVM VM with multiple serial ports. The kernel documentation notes that the last entry will be used for /dev/console https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-tty "What: /sys/class/tty/console/active          Shows the list of currently configured console devices, like 'tty1 ttyS0'. The last entry in the file is the active device connected to /dev/console.          The file supports poll() to detect virtual console switches." https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1960 "The last preferred console added will be used for kernel messages and stdin/out/err for init." The actual behavior is different and the console specified in the last console argument does not become an active one. As a result, SOL functionality is not possible to use unless only one ttyS<n> argument is specified in the kernel command line arguments. Setting the arguments to only contain the right one results in a proper behavior and I can see rx counters increasing in /proc/tty/driver/serial for the relevant port after I type something via the BMC. $ cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 journalctl -k | grep ttyS Dec 03 21:42:41 ubuntu kernel: Command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: Kernel command line: BOOT_IMAGE=/vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 Dec 03 21:42:41 ubuntu kernel: console [ttyS0] enabled Dec 03 21:42:41 ubuntu kernel: 00:02: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: 00:03: ttyS1 at I/O 0x2f8 (irq = 3, base_baud = 115200) is a 16550A Dec 03 21:42:41 ubuntu kernel: tty ttyS3: hash matches Full dmesg: http://paste.ubuntu.com/p/bV2pDc4Hdw/ $ cat /sys/class/tty/console/active ttyS0 tty0 $ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:78 rx:0 RTS|DTR 1: uart:16550A port:000002F8 irq:3 tx:0 rx:0 CTS|DSR|CD 2: uart:unknown port:000003E8 irq:4 3: uart:unknown port:000002E8 irq:3 # ... ~~~ GRUB setttings: # the ones that override /etc/default/grub $ cat /etc/default/grub.d/50-curtin-settings.cfg cat: cat: No such file or directory GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0,115200 console=ttyS1,115200" # disable grub os prober that might find other OS installs. GRUB_DISABLE_OS_PROBER=true GRUB_TERMINAL=console /etc/default/grub: https://paste.ubuntu.com/p/sdWQrY7JwN/ # grub.cfg: http://paste.ubuntu.com/p/zKGTqDh6sR/ # two entries, both with the proper arg and properly sent to the kernel cmdline based on /proc/cmdline grep ttyS grub.cfg         linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200          linux /vmlinuz-4.15.0-42-generic root=UUID=580a3c58-1040-4c7d-b94f-93230874caf5 ro console=tty0 console=ttyS0,115200 console=ttyS1,115200 ~~~ I managed to reproduce the exact same behavior on a VM with multiple 8250 serial ports. ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS0 ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg         linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS2,115200 console=ttyS1,115200 # changed to the following config with only ttyS1 present: ubuntu@maas-vhost5:~$ grep -RP ttyS /boot/grub/grub.cfg         linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200          linux /boot/vmlinuz-4.15.0-39-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # 1 tty passed only ubuntu@maas-vhost5:~$ cat /proc/cmdline BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS1,115200 # now it's shown as active ubuntu@maas-vhost5:~$ cat /sys/class/tty/console/active ttyS1 ubuntu@maas-vhost5:~$ sudo cat /proc/tty/driver/serial serinfo:1.0 driver revision: 0: uart:16550A port:000003F8 irq:4 tx:0 rx:0 CTS|DSR|CD 1: uart:16550A port:000002F8 irq:3 tx:14763 rx:0 RTS|CTS|DTR|DSR|CD 2: uart:16550A port:000003E8 irq:4 tx:0 rx:0 CTS|DSR|CD ~~~~ Relevant code: https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L2379 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1916 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1961 https://elixir.bootlin.com/linux/v4.15.18/source/kernel/printk/printk.c#L1886 --- ProblemType: Bug AlsaDevices: total 0 crw-rw---- 1 root audio 116, 1 Dec 6 14:38 seq crw-rw---- 1 root audio 116, 33 Dec 6 14:38 timer AplayDevices: Error: [Errno 2] No such file or directory: 'aplay': 'aplay' ApportVersion: 2.20.9-0ubuntu7.5 Architecture: amd64 ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord': 'arecord' AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: DistroRelease: Ubuntu 18.04 IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig': 'iwconfig' Lsusb: Bus 001 Device 002: ID 0627:0001 Adomax Technology Co., Ltd Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub MachineType: QEMU Standard PC (Q35 + ICH9, 2009) Package: linux (not installed) PciMultimedia: ProcFB: 0 qxldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-42-generic root=UUID=a60217c2-6752-4c69-afb9-55f86a2b6c1d ro console=ttyS0,115200 console=ttyS1,115200 ProcVersionSignature: User Name 4.15.0-42.45-generic 4.15.18 RelatedPackageVersions: linux-restricted-modules-4.15.0-42-generic N/A linux-backports-modules-4.15.0-42-generic N/A linux-firmware 1.173.2 RfKill: Error: [Errno 2] No such file or directory: 'rfkill': 'rfkill' Tags: bionic uec-images Uname: Linux 4.15.0-42-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm audio cdrom dialout dip floppy lxd netdev plugdev sudo video _MarkForUpload: True dmi.bios.date: 04/01/2014 dmi.bios.vendor: SeaBIOS dmi.bios.version: 1.10.2-1ubuntu1 dmi.chassis.type: 1 dmi.chassis.vendor: QEMU dmi.chassis.version: pc-q35-2.11 dmi.modalias: dmi:bvnSeaBIOS:bvr1.10.2-1ubuntu1:bd04/01/2014:svnQEMU:pnStandardPC(Q35+ICH9,2009):pvrpc-q35-2.11:cvnQEMU:ct1:cvrpc-q35-2.11: dmi.product.name: Standard PC (Q35 + ICH9, 2009) dmi.product.version: pc-q35-2.11 dmi.sys.vendor: QEMU
2018-12-06 14:45:25 Dmitrii Shcherbakov attachment added CRDA.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219754/+files/CRDA.txt
2018-12-06 14:45:27 Dmitrii Shcherbakov attachment added CurrentDmesg.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219755/+files/CurrentDmesg.txt
2018-12-06 14:45:28 Dmitrii Shcherbakov attachment added Lspci.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219756/+files/Lspci.txt
2018-12-06 14:45:29 Dmitrii Shcherbakov attachment added ProcCpuinfo.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219757/+files/ProcCpuinfo.txt
2018-12-06 14:45:31 Dmitrii Shcherbakov attachment added ProcCpuinfoMinimal.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219758/+files/ProcCpuinfoMinimal.txt
2018-12-06 14:45:32 Dmitrii Shcherbakov attachment added ProcEnviron.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219759/+files/ProcEnviron.txt
2018-12-06 14:45:32 Dmitrii Shcherbakov attachment added ProcInterrupts.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219760/+files/ProcInterrupts.txt
2018-12-06 14:45:33 Dmitrii Shcherbakov attachment added ProcModules.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219761/+files/ProcModules.txt
2018-12-06 14:45:34 Dmitrii Shcherbakov attachment added UdevDb.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219762/+files/UdevDb.txt
2018-12-06 14:45:36 Dmitrii Shcherbakov attachment added WifiSyslog.txt https://bugs.launchpad.net/bugs/1807140/+attachment/5219763/+files/WifiSyslog.txt
2018-12-06 14:46:19 Dmitrii Shcherbakov linux (Ubuntu): status Incomplete Confirmed
2019-07-24 21:32:41 Brad Figg tags apport-collected bionic cpe-onsite uec-images apport-collected bionic cpe-onsite cscc uec-images