[ovs-dev] [PATCH V2 2/2] rhel: Add post installation check for kernel modules

[Gregory Rose]

On 1/12/2018 9:37 AM, Guru Shetty wrote:
>
>
> On 12 January 2018 at 08:37, Greg Rose <gvrose8192 at gmail.com 
> <mailto:gvrose8192 at gmail.com>> wrote:
>
>     A bug in RHEL 7.2 has been found in which a customer who installed
>     a RHEL 7.2 openvswitch kernel module rpm with a slightly different
>     minor build number than the running kernel found that the kernel
>     modules were installed to the wrong directory.
>
>     After the installation the new openvswitch kernel modules were
>     installed to:
>     /lib/modules/3.10.0-327.22.2.el7.x86_64/extra/openvswitch
>
>     But the running kernel was 3.10.0-327.el7.x86_64 and after the
>     installation was complete the kernel modules in the installed
>     directory were not linked to the "weak-updates" directory in
>     the running kernel.  So a critical bug was encountered in
>     which the in-tree openvswitch kernel module was loaded instead
>     of the one the customer explicitly installed with the rpm.
>
>     This patch replicates ./extra/openvswitch directory with kernel
>     modules, if for the currently running kernel there is neither
>     a ./extra/openvswitch nor ./weak-update/openvswitch directory.
>
>     Signed-off-by: Greg Rose <gvrose8192 at gmail.com
>     <mailto:gvrose8192 at gmail.com>>
>
>     ---
>
>     V2 - Incorporate feedback from V1
>     ---
>      rhel/openvswitch.spec.in <http://openvswitch.spec.in> | 26
>     ++++++++++++++++++++++++++
>      1 file changed, 26 insertions(+)
>
>     diff --git a/rhel/openvswitch.spec.in <http://openvswitch.spec.in>
>     b/rhel/openvswitch.spec.in <http://openvswitch.spec.in>
>     index e510d35..b5b5122 100644
>     --- a/rhel/openvswitch.spec.in <http://openvswitch.spec.in>
>     +++ b/rhel/openvswitch.spec.in <http://openvswitch.spec.in>
>     @@ -169,6 +169,32 @@ fi
>      /sbin/chkconfig --add openvswitch
>      /sbin/chkconfig openvswitch on
>
>     +# In some cases a kernel module rpm will have a different minor build
>     +# version than the currently running kernel.  In this case the kernel
>     +# modules will be installed but not to the kernel modules directory
>     +# of the currently running kernel. Check and copy modules if
>     +# necessary.
>     +# This is a bug that has only been found to occur on RHEL 7.2.
>     +if [[ ! -d /lib/modules/$(uname -r)/extra/openvswitch && \
>     +      ! -d /lib/modules/$(uname -r)/weak-updates/openvswitch ]]; then
>
>
> This check may not be good enough. If we are doing a upgrade of OVS on 
> the system (say from 2.7 to 2.9) and previously we had something in  
> /lib/modules/$(uname -r)/weak-updates/openvswitch then we are no 
> longer going to add the newer version there.

But that would assure that a previous attempt to install the openvswitch 
kernel modules rpm had succeeded, which means this system doesn't have 
the bug that is prompting this patch.  That means the newly installed 
kernel modules have been placed in the right kernel modules directory.  
So the test is correct.

>     +    found="false"
>     +    for i in `ls -t /lib/modules`
>     +    do
>     +        if [ -d /lib/modules/$i/extra/openvswitch ]; then
>
> This will not help either. There is a possibility of multiple kernels 
> installed and it looks like we will choose one randomly. We should 
> only look at the path where the current rpm actually installed our files.

I tried it on a system with multiple installed kernels and it does work 
because the sort by time will pick the most recently installed kernel 
modules directory which would be the one where the just installed kernel 
modules rpm had gone to (erroneously I should add).
>
>     +            mkdir -p /lib/modules/$(uname -r)/extra
>     +            cp -r --preserve "/lib/modules/$i/extra/openvswitch" \
>     +            /lib/modules/$(uname -r)/extra
>     +            found="true"
>     +            break
>     +        fi
>     +    done
>     +    if [ "$found" != "true" ]; then
>     +        echo "Error in openvswitch kernel modules installation"
>     +    else
>     +        /usr/sbin/depmod -a
>     +    fi
>     +fi
>     +
>      %post selinux-policy
>      /usr/sbin/semodule -i
>     %{_datadir}/selinux/packages/%{name}/openvswitch-custom.pp &>
>     /dev/null || :
>
>     --
>     1.8.3.1
>
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>
>