** 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 - + Verification can be made from a 2nd terminal, run : + $ 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 + $ 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
-- You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gdm3 in Ubuntu. https://bugs.launchpad.net/bugs/1817738 Title: Can't change virtual terminal when auto-login is enabled To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1817738/+subscriptions -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs
