** Description changed:

  [Impact]
  
  When AutomaticLogin is enable in gdm3. The "chvt" command hangs forever,
  preventing from changing foreground virtual terminal.
  
  [Test case]
  
  1) Install Bionic/18.04LTS Desktop
  
  2) Enable AutomaticLogin
   2.1) Modify /etc/gdm3/custom.conf
  # Enabling automatic login
    AutomaticLoginEnable = true
    AutomaticLogin = <YOUR_USER>
  
  3) Reboot your system and make sure AutoLogin works by not requesting
  password before opening the <YOUR_USER> session.
  
  4) sudo chvt 4 ## chvt will hang here.
  
  5) From a 2nd terminal, run :
   5.1) cat /proc/$(pidof chvt)/stack
  
  [<0>] __vt_event_wait.isra.2.part.3+0x40/0x90
  [<0>] vt_waitactive+0x80/0xd0
  [<0>] vt_ioctl+0xd26/0x1140
  [<0>] tty_ioctl+0xf6/0x8c0
  [<0>] do_vfs_ioctl+0xa8/0x630
  [<0>] SyS_ioctl+0x79/0x90
  [<0>] do_syscall_64+0x73/0x130
  [<0>] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
  [<0>] 0xffffffffffffffff
  
  It's basically waiting for the VT to be activated, but it never happens.
  
  [Potential regression]
+ 
+ Low.
+ 
+ Current gdm3 run autologin display on tty1 . tty1 is really meant for
+ the login screen. This commit changes autologin to not use the initial
+ vt.
  
  [Other information]
  
  * Upstream fix:
  https://github.com/GNOME/gdm/commit/39fb4ff6
  
  $ git describe --contains 39fb4ff6
  3.30.1~2^2~3
  
  $ rmadision gdm3
   ==> gdm3 | 3.28.3-0ubuntu18.04.4       | bionic-updates   | ...
       gdm3 | 3.30.1-1ubuntu5             | cosmic           | ...
       gdm3 | 3.30.1-1ubuntu5             | disco            | ...
       gdm3 | 3.30.1-1ubuntu5.1           | cosmic-security  | ...
       gdm3 | 3.30.1-1ubuntu5.1           | cosmic-updates   | ...
       gdm3 | 3.31.4+git20190225-1ubuntu1 | disco-proposed   | ...
  
  [Original Description]
  sudo strace chvt 4
  execve("/bin/chvt", ["chvt", "4"], 0x7ffd63e5c758 /* 17 vars */) = 0
  brk(NULL) = 0x561e18430000
  access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
  access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
  fstat(3, {st_mode=S_IFREG|0644, st_size=74655, ...}) = 0
  mmap(NULL, 74655, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f5059e7d000
  close(3) = 0
  access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
  read(3, 
"\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\260\34\2\0\0\0\0\0"..., 832) = 
832
  fstat(3, {st_mode=S_IFREG|0755, st_size=2030544, ...}) = 0
  mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 
0x7f5059e7b000
  mmap(NULL, 4131552, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 
0x7f5059878000
  mprotect(0x7f5059a5f000, 2097152, PROT_NONE) = 0
  mmap(0x7f5059c5f000, 24576, PROT_READ|PROT_WRITE, 
MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e7000) = 0x7f5059c5f000
  mmap(0x7f5059c65000, 15072, PROT_READ|PROT_WRITE, 
MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f5059c65000
  close(3) = 0
  arch_prctl(ARCH_SET_FS, 0x7f5059e7c500) = 0
  mprotect(0x7f5059c5f000, 16384, PROT_READ) = 0
  mprotect(0x561e17e87000, 4096, PROT_READ) = 0
  mprotect(0x7f5059e90000, 4096, PROT_READ) = 0
  munmap(0x7f5059e7d000, 74655) = 0
  brk(NULL) = 0x561e18430000
  brk(0x561e18451000) = 0x561e18451000
  openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
  fstat(3, {st_mode=S_IFREG|0644, st_size=10281936, ...}) = 0
  mmap(NULL, 10281936, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f5058ea9000
  close(3) = 0
  openat(AT_FDCWD, "/proc/self/fd/0", O_RDWR) = 3
  ioctl(3, TCGETS, {B38400 opost isig icanon echo ...}) = 0
  ioctl(3, KDGKBTYPE, 0x7ffdcdb0efa7) = -1 ENOTTY (Inappropriate ioctl for 
device)
  close(3) = 0
  openat(AT_FDCWD, "/dev/tty", O_RDWR) = 3
  ioctl(3, TCGETS, {B38400 opost isig icanon echo ...}) = 0
  ioctl(3, KDGKBTYPE, 0x7ffdcdb0efa7) = -1 ENOTTY (Inappropriate ioctl for 
device)
  close(3) = 0
  openat(AT_FDCWD, "/dev/tty0", O_RDWR) = 3
  ioctl(3, TCGETS, {B38400 opost isig icanon echo ...}) = 0
  ioctl(3, KDGKBTYPE, 0x7ffdcdb0efa7) = 0
  ioctl(3, VT_ACTIVATE, 0x4) = 0
  ioctl(3, VT_WAITACTIVE, 0x4
  
  VT_ACTIVATE will cause a switch to VT number.
  VT_WAITACTIVE will sleep/wait until the specified VT has been activated.
  
  $ sudo cat /proc/$(pidof chvt)/stack
  [<0>] __vt_event_wait.isra.2.part.3+0x40/0x90
  [<0>] vt_waitactive+0x80/0xd0
  [<0>] vt_ioctl+0xd26/0x1140
  [<0>] tty_ioctl+0xf6/0x8c0
  [<0>] do_vfs_ioctl+0xa8/0x630
  [<0>] SyS_ioctl+0x79/0x90
  [<0>] do_syscall_64+0x73/0x130
  [<0>] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
  [<0>] 0xffffffffffffffff
  
  Enable debuglogs doesn't provide additional details.
  
  As soon as auto-login is turned off, chvt is back to normal.
  
  The above has been reproduced on Ubuntu:
  - Ubuntu Bionic w/ gdm3 3.28.3 & kbd 2.0.4

** Description changed:

  [Impact]
  
  When AutomaticLogin is enable in gdm3. The "chvt" command hangs forever,
  preventing from changing foreground virtual terminal.
  
  [Test case]
  
  1) Install Bionic/18.04LTS Desktop
  
  2) Enable AutomaticLogin
   2.1) Modify /etc/gdm3/custom.conf
  # Enabling automatic login
    AutomaticLoginEnable = true
    AutomaticLogin = <YOUR_USER>
  
  3) Reboot your system and make sure AutoLogin works by not requesting
  password before opening the <YOUR_USER> session.
  
  4) sudo chvt 4 ## chvt will hang here.
  
  5) From a 2nd terminal, run :
   5.1) cat /proc/$(pidof chvt)/stack
  
  [<0>] __vt_event_wait.isra.2.part.3+0x40/0x90
  [<0>] vt_waitactive+0x80/0xd0
  [<0>] vt_ioctl+0xd26/0x1140
  [<0>] tty_ioctl+0xf6/0x8c0
  [<0>] do_vfs_ioctl+0xa8/0x630
  [<0>] SyS_ioctl+0x79/0x90
  [<0>] do_syscall_64+0x73/0x130
  [<0>] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
  [<0>] 0xffffffffffffffff
  
  It's basically waiting for the VT to be activated, but it never happens.
  
  [Potential regression]
  
  Low.
  
  Current gdm3 run autologin display on tty1 . tty1 is really meant for
  the login screen. This commit changes autologin to not use the initial
  vt.
+ 
+ Exactly like when autologin isn't enable.
+ 
+ From a machine with autologin disable:
+ 
+ /etc/gdm3/customer.conf
+ # Enabling automatic login
+ #  AutomaticLoginEnable = true
+ #  AutomaticLogin = user1
+ 
+ $ sudo fgconsole 
+ 2
  
  [Other information]
  
  * Upstream fix:
  https://github.com/GNOME/gdm/commit/39fb4ff6
  
  $ git describe --contains 39fb4ff6
  3.30.1~2^2~3
  
  $ rmadision gdm3
   ==> gdm3 | 3.28.3-0ubuntu18.04.4       | bionic-updates   | ...
       gdm3 | 3.30.1-1ubuntu5             | cosmic           | ...
       gdm3 | 3.30.1-1ubuntu5             | disco            | ...
       gdm3 | 3.30.1-1ubuntu5.1           | cosmic-security  | ...
       gdm3 | 3.30.1-1ubuntu5.1           | cosmic-updates   | ...
       gdm3 | 3.31.4+git20190225-1ubuntu1 | disco-proposed   | ...
  
  [Original Description]
  sudo strace chvt 4
  execve("/bin/chvt", ["chvt", "4"], 0x7ffd63e5c758 /* 17 vars */) = 0
  brk(NULL) = 0x561e18430000
  access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
  access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
  fstat(3, {st_mode=S_IFREG|0644, st_size=74655, ...}) = 0
  mmap(NULL, 74655, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f5059e7d000
  close(3) = 0
  access("/etc/ld.so.nohwcap", F_OK) = -1 ENOENT (No such file or directory)
  openat(AT_FDCWD, "/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
  read(3, 
"\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\260\34\2\0\0\0\0\0"..., 832) = 
832
  fstat(3, {st_mode=S_IFREG|0755, st_size=2030544, ...}) = 0
  mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 
0x7f5059e7b000
  mmap(NULL, 4131552, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 
0x7f5059878000
  mprotect(0x7f5059a5f000, 2097152, PROT_NONE) = 0
  mmap(0x7f5059c5f000, 24576, PROT_READ|PROT_WRITE, 
MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e7000) = 0x7f5059c5f000
  mmap(0x7f5059c65000, 15072, PROT_READ|PROT_WRITE, 
MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f5059c65000
  close(3) = 0
  arch_prctl(ARCH_SET_FS, 0x7f5059e7c500) = 0
  mprotect(0x7f5059c5f000, 16384, PROT_READ) = 0
  mprotect(0x561e17e87000, 4096, PROT_READ) = 0
  mprotect(0x7f5059e90000, 4096, PROT_READ) = 0
  munmap(0x7f5059e7d000, 74655) = 0
  brk(NULL) = 0x561e18430000
  brk(0x561e18451000) = 0x561e18451000
  openat(AT_FDCWD, "/usr/lib/locale/locale-archive", O_RDONLY|O_CLOEXEC) = 3
  fstat(3, {st_mode=S_IFREG|0644, st_size=10281936, ...}) = 0
  mmap(NULL, 10281936, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f5058ea9000
  close(3) = 0
  openat(AT_FDCWD, "/proc/self/fd/0", O_RDWR) = 3
  ioctl(3, TCGETS, {B38400 opost isig icanon echo ...}) = 0
  ioctl(3, KDGKBTYPE, 0x7ffdcdb0efa7) = -1 ENOTTY (Inappropriate ioctl for 
device)
  close(3) = 0
  openat(AT_FDCWD, "/dev/tty", O_RDWR) = 3
  ioctl(3, TCGETS, {B38400 opost isig icanon echo ...}) = 0
  ioctl(3, KDGKBTYPE, 0x7ffdcdb0efa7) = -1 ENOTTY (Inappropriate ioctl for 
device)
  close(3) = 0
  openat(AT_FDCWD, "/dev/tty0", O_RDWR) = 3
  ioctl(3, TCGETS, {B38400 opost isig icanon echo ...}) = 0
  ioctl(3, KDGKBTYPE, 0x7ffdcdb0efa7) = 0
  ioctl(3, VT_ACTIVATE, 0x4) = 0
  ioctl(3, VT_WAITACTIVE, 0x4
  
  VT_ACTIVATE will cause a switch to VT number.
  VT_WAITACTIVE will sleep/wait until the specified VT has been activated.
  
  $ sudo cat /proc/$(pidof chvt)/stack
  [<0>] __vt_event_wait.isra.2.part.3+0x40/0x90
  [<0>] vt_waitactive+0x80/0xd0
  [<0>] vt_ioctl+0xd26/0x1140
  [<0>] tty_ioctl+0xf6/0x8c0
  [<0>] do_vfs_ioctl+0xa8/0x630
  [<0>] SyS_ioctl+0x79/0x90
  [<0>] do_syscall_64+0x73/0x130
  [<0>] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
  [<0>] 0xffffffffffffffff
  
  Enable debuglogs doesn't provide additional details.
  
  As soon as auto-login is turned off, chvt is back to normal.
  
  The above has been reproduced on Ubuntu:
  - Ubuntu Bionic w/ gdm3 3.28.3 & kbd 2.0.4

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https://bugs.launchpad.net/bugs/1817738

Title:
  Can't change virtual terminal when auto-login is enabled

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