package:grub-efi-amd64-signed:1.158+2.04-1ubuntu37 Setting up grub-efi-amd64-signed (1.158+2.04-1ubuntu37) ... Trying to migrate /boot/efi into esp config Installing grub to /boot/efi. Installing for x86_64-efi platform. grub-install: warning: Cannot read EFI Boot* variables. grub-install: warning: read_file: could not read from file: Input/output error. grub-install: warning: vars_get_variable: read_file(/sys/firmware/efi/vars/Boot0006-8be4df61-93ca-11d2-aa0d-00e098032b8c/raw_var) failed: Input/output error. grub-install: warning: efi_get_variable: ops->get_variable failed: Input/output error. grub-install: error: failed to register the EFI boot entry: Input/output error. dpkg: error processing package grub-efi-amd64-signed (--configure): installed grub-efi-amd64-signed package post-installation script subprocess returned error exit status 1