Hi Thomas,
On 2023-05-20 02:54:23+0200, Thomas Deutschmann wrote:
> Hi,
>
> I didn't find a kernel requirement in latest util-linux 2.39 release notes
> and because a fallback is mentioned I gave it a try on a system running
> latest LTS kernel 5.10.180.
>
> After updating to util=linux 2.39 system immediately failed when trying to
> use mount command.
>
> I.e.
>
> mount --make-slave /proc
>
> failed with:
>
> > mount: /proc: mount(2) system call failed: Function not implemented.
> > dmesg(1) may have more information after failed mount system call.
>
> Nothing in dmesg about it.
>
>
> strace shows
>
> > mount_setattr(3, "", AT_EMPTY_PATH, {attr_set=0, attr_clr=0, propagation=MS_SLAVE, userns_fd=0}, 32) = -1 ENOSYS (Function not implemented)
Thanks for the report!
There is also a ticket about this here:
https://github.com/util-linux/util-linux/issues/2247 .
> Configure output shows
>
> > checking for syscall mount_setattr... SYS_mount_setattr
>
> But this is coming from Linux headers (I have most recent Linux headers from
> kernel 6.3 installed).
>
> Not sure if this is the problem but using most recent Linux headers with
> older kernel shouldn't be a problem in general according to https://sourceware.org/glibc/wiki/FAQ#What_version_of_the_Linux_kernel_headers_should_be_used.3F
Please note that this is a document about glibc, not util-linux.
Nevertheless the same concept also applies to util-linux.
> Booting a newer kernel (I tried 5.15.112) helped (I guess because the system
> call was added in 5.12).
Could you test the fix proposed in
https://github.com/util-linux/util-linux/pull/2248 ?
(For testing on a real system you only need the changes to
libmount/src/hook_mount.c, ignore the testing stuff)
Thomas
