[pve-devel] [PATCH ct/common] mount point hotplugging & new mount api

[Oguz Bektas]

hi,

built the latest git version of pve-common and pve-container with
wolfgang's patches.

with running kernel: 5.0.21-4-pve
and the latest pve-kernel-5.3

found a small issue while testing.

when one has an older kernel and tries to hotplug a mountpoint

-----------------------------------------------
Parameter verification failed. (400)

mp1: unable to hotplug mp1: Can't use an undefined value as a symbol
reference at /usr/share/perl5/PVE/LXC.pm line 1670. 
-----------------------------------------------

and around this line is:

-----------------------------------------------

        PVE::Tools::move_mount(
            fileno($mount_fd),
            "",
            &AT_FDCWD,
            $mp->{mp},
            &MOVE_MOUNT_F_EMPTY_PATH, # line 1670
        );
    });
}

-----------------------------------------------

so i'm guessing since that syscall doesn't exist in older kernels,
we get an undefined value.

it would be better to handle this error with something more
user-friendly and verbose.

i'm still testing and will write here if i notice something else.