** Description changed:

  [Bug description]
  
  On a jammy installation, which was upgraded from focal, after a full-
  upgrade and a reboot,
  
  I enter the LUKS password to decrypt the disk. Then I get the following
  error:
  
  libgcc_s.so.1 must be installed for pthread_exit to work
  
  After the error is shown, the system asks for the password again (which
  never works, always throwing the same error).
  
  [Root cause]
  
  I was able to decrypt the disk with the same password by booting from a
  live usb. Which allowed further investigation.
  
  The error shown in the LUKS password prompt menu comes from
  https://github.com/bminor/glibc/blob/glibc-2.34/nptl/pthread_exit.c#L31-L32, 
which indeed shows that pthread_exit fails when libgcc_s.so.1 is missing.
  
  From
  
https://git.launchpad.net/ubuntu/+source/initramfs-tools/tree/hook-functions?h=import/0.140ubuntu10#n260,
  we noticed that libgcc_s.so.1 is only copied if
  
  1) copy_exec is called for a binary directly linked to libgcc_s.so.1, or
  2) copy_exec is called for a binary linked to libpthread
  
  The cryptsetup initramfs hook, calls copy_exec for /sbin/cryptsetup,
  which is linked to libargon2.so.1, which is linked to libpthread.so.0.
  This covers case (2) above. As a consequence, libgcc_s.so.1 is copied to
  the initrd image and the error reported here is not seen.
  
  However, since glibc 2.34, libpthread is shipped within glibc, and the
  binaries are no longer linked to libpthread.so.0. As a consequence, an
  argon2 package built with glibc 2.32 will no longer be linked to
  libpthread.so.0 and libgcc_s.so.1 will no longer be copied to the initrd
  image. Triggering the reported error.
  
  This can be verified in these two argon2 builds, from the same sources,
  but with different glibc versions:
  
  
https://launchpad.net/ubuntu/+source/argon2/0~20171227-0.2build21.04.0/+build/21066610
  
https://launchpad.net/ubuntu/+source/argon2/0~20171227-0.2build22/+build/22255217
  
  Still lvm2 is a seeded package, which Recommends thin-provisioning-
  tools. thin-provisioning-tools ships a initramfs hook that calls
  copy_exec for /usr/sbin/pdata_tools, which is directly linked to
  libgcc_s.so.1. This covers the case (1) above and should suffice to
  ensure the boot process works properly.
  
  Since thin-provisioning-tools is just a recommends for lvm2, it could be
  removed from the system (and indeed, for some reason, was not present in
  my focal=>jammy installation). In this case, a new kernel installation
  should trigger the reported error.
  
  [Reproducer]
  
  - Install jammy with a LUKS encrypted disk
  - remove thin-provisioning-tools
  - perform a full-upgrade (make sure the kernel was upgraded or run 
update-initramfs manually)
  - reboot and verify you can no longer get past the decrypt password prompt 
screen
  
  [Workaround]
  
  A workaround for anyone affected would be to install thin-provisioning-
  tools and run update-initramfs.
  
- 
  [Impact]
  
  Users upgrading from focal to jammy will eventually be locked out of
- their systems
+ their systems in case they are using LUKS encryption.
  
  [Additional information]
  
  While this issue is similar to
  https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1861757,
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=950254, and
  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=950551,
  This is a different bug, with a different root cause.
  
  Thanks to sergiodj for the pairing session on the root cause analysis.

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https://bugs.launchpad.net/bugs/1958594

Title:
  Boot error: libgcc_s.so.1 must be installed for pthread_exit to work

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