Comment 0 for bug 1965288

On system conforming to the Embedded Base Boot Requirements (EBBR) specification it is allowable that the UEFI runtime service SetVariable() is not available. This means that the BOOTXXXX variable for invoking GRUB cannot be set automatically. Instead this has to be left to the user.

        Traceback (most recent call last):
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/commands/main.py", line 202, in main
            ret = args.func(args)
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/commands/curthooks.py", line 1886, in curthooks
            builtin_curthooks(cfg, target, state)
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/commands/curthooks.py", line 1851, in builtin_curthooks
            setup_grub(cfg, target, osfamily=osfamily,
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/commands/curthooks.py", line 804, in setup_grub
            install_grub(instdevs, target, uefi=uefi_bootable, grubcfg=grubcfg)
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/commands/install_grub.py", line 401, in install_grub
            in_chroot.subp(cmd, env=env, capture=True)
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/util.py", line 780, in subp
            return subp(*args, **kwargs)
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/util.py", line 275, in subp
            return _subp(*args, **kwargs)
          File "/snap/subiquity/x1/lib/python3.8/site-packages/curtin/util.py", line 139, in _subp
            raise ProcessExecutionError(stdout=out, stderr=err,
        curtin.util.ProcessExecutionError: Unexpected error while running command.
        Command: ['unshare', '--fork', '--pid', '--', 'chroot', '/target', '/usr/lib/grub/grub-multi-install']
        Exit code: 1
        Reason: -
        Stdout: ''
        Stderr: Installing grub to /boot/efi.
                Installing for riscv64-efi platform.
                grub-install: warning: Cannot set EFI variable Boot0000.
                grub-install: warning: efivarfs_set_variable: failed to create /sys/firmware/efi/efivars/Boot0000-8be4df61-93ca-11d2-aa0d-00e098032b8c for writing: Read-only file system.
                grub-install: warning: _efi_set_variable_mode: ops->set_variable() failed: Read-only file system.
                grub-install: error: failed to register the EFI boot entry: Read-only file system.

        Unexpected error while running command.
        Command: ['unshare', '--fork', '--pid', '--', 'chroot', '/target', '/usr/lib/grub/grub-multi-install']
        Exit code: 1
        Reason: -
        Stdout: ''
        Stderr: Installing grub to /boot/efi.
                Installing for riscv64-efi platform.
                grub-install: warning: Cannot set EFI variable Boot0000.
                grub-install: warning: efivarfs_set_variable: failed to create /sys/firmware/efi/efivars/Boot0000-8be4df61-93ca-11d2-aa0d-00e098032b8c for writing: Read-only file system.
                grub-install: warning: _efi_set_variable_mode: ops->set_variable() failed: Read-only file system.
                grub-install: error: failed to register the EFI boot entry: Read-only file system.