Re: rdma-core spec weird behavior on Fedora

[Jason Gunthorpe <jgg@nvidia.com>]

On Mon, Feb 08, 2021 at 05:59:11PM +0200, Leon Romanovsky wrote:
> On Mon, Feb 08, 2021 at 11:35:31AM -0400, Jason Gunthorpe wrote:
> > On Mon, Feb 08, 2021 at 04:31:00PM +0200, Leon Romanovsky wrote:
> > > On Mon, Feb 08, 2021 at 10:08:24AM -0400, Jason Gunthorpe wrote:
> > > > On Mon, Feb 08, 2021 at 03:31:37PM +0200, Leon Romanovsky wrote:
> > > > > On Mon, Feb 08, 2021 at 09:21:15AM -0400, Jason Gunthorpe wrote:
> > > > > > On Mon, Feb 08, 2021 at 03:10:53PM +0200, Leon Romanovsky wrote:
> > > > > > > On Mon, Feb 08, 2021 at 08:59:00AM -0400, Jason Gunthorpe wrote:
> > > > > > > > On Sun, Feb 07, 2021 at 10:06:49AM +0200, Leon Romanovsky wrote:
> > > > > > > > > Hi Honggang,
> > > > > > > > >
> > > > > > > > > Your commit b02de521022a ("redhat: Remove base package dependency from all sub-packages")
> > > > > > > > > removes protection from rdma-core when user performs "dnf autoremove".
> > > > > > > > >
> > > > > > > > > Before your patch, systemd was dependent on libibverbs and latter
> > > > > > > > > required rdma-core. After your patch, the last link is lost and
> > > > > > > > > rdma-core marked as orphaned package.
> > > > > > > > >
> > > > > > > > > Any attempt to install rdma-core as standalone package will have the
> > > > > > > > > following errors, due to the library dependency of udevadm.
> > > > > > > > > [leonro@c rdma-core]$ ldd /sbin/udevadm | grep verbs
> > > > > > > > > 	libibverbs.so.1 => not found
> > > > > > > >
> > > > > > > > well that makes no sense, since when is udevadm connected to
> > > > > > > > libibverbs?
> > > > > > > >
> > > > > > > > $ ldd `which udevadm`
> > > > > > > > 	linux-vdso.so.1 (0x00007ffcc09ef000)
> > > > > > > > 	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f394bec3000)
> > > > > > > > 	libkmod.so.2 => /lib/x86_64-linux-gnu/libkmod.so.2 (0x00007f394bea8000)
> > > > > > > > 	libacl.so.1 => /lib/x86_64-linux-gnu/libacl.so.1 (0x00007f394be9d000)
> > > > > > > > 	libblkid.so.1 => /lib/x86_64-linux-gnu/libblkid.so.1 (0x00007f394be46000)
> > > > > > > > 	libselinux.so.1 => /lib/x86_64-linux-gnu/libselinux.so.1 (0x00007f394be1b000)
> > > > > > > > 	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f394bdf8000)
> > > > > > > > 	/lib64/ld-linux-x86-64.so.2 (0x00007f394c1b6000)
> > > > > > > > 	liblzma.so.5 => /lib/x86_64-linux-gnu/liblzma.so.5 (0x00007f394bdcd000)
> > > > > > > > 	libcrypto.so.1.1 => /lib/x86_64-linux-gnu/libcrypto.so.1.1 (0x00007f394baf7000)
> > > > > > > > 	libpcre2-8.so.0 => /lib/x86_64-linux-gnu/libpcre2-8.so.0 (0x00007f394ba67000)
> > > > > > > > 	libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f394ba61000)
> > > > > > >
> > > > > > > This is from my laptop and it is connected:
> > > > > >
> > > > > > Well, that is crazy, udevadm uses libpcap on Fedora which is linked to verbs
> > > > > >
> > > > > > But it still doesn't make sense, how did you get a in a situation
> > > > > > where this is no libibverbs installed even though there should be
> > > > > > dependencies from udevadm preventing that?
> > > > >
> > > > > It was part of my experiments and it is not the issue which we need to solve.
> > > > >
> > > > > Our two problems are that "dnf autoremove" removes rdma-core and you can't
> > > > > install it separately after Honggang's patch.
> > > >
> > > > why not? libibverbs should not be removed by autoremoved?
> > >
> > > During installation of rdma-core, DNF throws errors if libibverbs
> > > doesn't exist, which was in my case when I wanted to reinstall rdma-core
> > > to something new.
> >
> > dnf shouldn't let you remove libibvebs, so how did it get removed?
> 
> I built rdma-core RPM with latest code, issued "dnf install rdma-core
> ...", which passed with error and left system with "unknown" library.

Hum.

In DEB land if a post install script called some other program, like
udevadm, then it would have to pre-depend on that program so it could
be fully ready to run. Pre-depending would ensure that libibverbs was
swapped out somewhat atomically and the system wouldn't try to
configure rdma-core when libibverbs was not installed during a
transaction to change things around.

Sounds like some dnf expert should take a look at what is going on
here

But also, I don't think Fedora should have libverbs as an mandatory
package in every system for whateve udev is doing with libcap,
something really weird is going on that udev needs pcap

Jason