Public bug reported:

The `perf` profiling tool, and a few other tools, are part of the Linux
project. Ubuntu gets them from a package specific to the running kernel
version, and uses wrapper scripts installed as e.g. /usr/bin/perf to
dispatch to the appropriate version for the running kernel. This appears
to involve not only checking the actual kernel version number (e.g.
4.15.0) but also the patch level/build number and flavor that Ubuntu
adds (e.g. 4.15.0-62-generic) if found in the kernel version.

This is perfectly fine on a real system, where Ubuntu's package manager
is actually in control of the kernel. But Ubuntu is also fantastically
popular as a base for Docker images, and in a Docker container you have
to take your lumps and run on whatever kernel version the host happens
to be using, even if the host isn't using an official Ubuntu kernel, or
running Ubuntu at all.

As currently designed, the linux-tools-common wrapper scripts cannot
work reliably in a Docker environment.

When running in my particular Kubernetes environment (where the host is
some kind of Red Hat Enterprise Linux derivative), this problem
manifests as the following exchange:

root@adamnovak-pod:/vg# perf record ls
WARNING: perf not found for kernel 3.10.0

  You may need to install the following packages for this specific kernel:
    linux-tools-3.10.0

  You may also want to install one of the following packages to keep up to date:
    linux-tools
root@adamnovak-pod:/vg# apt install linux-tools-3.10.0
Reading package lists... Done
Building dependency tree       
Reading state information... Done
E: Unable to locate package linux-tools-3.10.0
E: Couldn't find any package by glob 'linux-tools-3.10.0'
E: Couldn't find any package by regex 'linux-tools-3.10.0'

However, the perf binary I happen to have installed, when I get it to
try to run, at least appears to work, despite the kernel version
mismatch. In larger tests, I've gotten perfectly fine profiling data.

root@adamnovak-pod:/vg# /usr/lib/linux-tools/4.15.0-62-generic/perf record ls
bin  deps  perf.data  scripts
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.002 MB perf.data (10 samples) ]
root@adamnovak-pod:/vg# 

So it is not clear that the level of specificity enforced by the wrapper
scripts is actually necessary.

There are a few potential solutions I can see to this problem:

1. Modify the scripts to treat the lack of the exact right tool version
being installed as a warning instead of an error, and have them select
the closest version to run instead.

2. Create linux-tools-3.10.0 ish through linux-tools-5.x.x packages,
containing builds of perf and co. derived from those official mainline
kernels, and a metapackage to install all of them. Then the package that
you get prompted to install when running in a container will exist, and
you will be able to install it to have a toolset that has a high
probability of being compatible with the kernel you are running on. A
container that needs to be portable between different hosts can install
the metapackage.

3. Create a package that conflicts with linux-tools-common and provides
some arbitrary version of the tools. People who want a toolset that can
run in a container can install that package instead, and bear the
responsibility for what happens if the tools provided don't work with
the kernel that happens to be running.

4. Hook into the alternatives system; allow the user to switch between
packages providing the tools for different kernel versions, with the
default being the dispatch script.

The workaround I am currently using is running this as soon as I get
inside the container, to clobber the wrapper script with whatever actual
binary I have installed:

cp /usr/lib/linux-tools/*/perf /usr/bin/perf

However, this is a pretty terrible hack.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-tools-common 4.15.0-62.69
ProcVersionSignature: Ubuntu 4.15.0-62.69-generic 4.15.18
Uname: Linux 4.15.0-62-generic x86_64
AlsaDevices: Error: command ['ls', '-l', '/dev/snd/'] failed with exit code 2: 
ls: cannot access '/dev/snd/': No such file or directory
AplayDevices: Error: [Errno 2] No such file or directory: 'aplay': 'aplay'
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: amd64
ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord': 'arecord'
AudioDevicesInUse: Error: [Errno 2] No such file or directory: 'fuser': 'fuser'
CurrentDmesg: Error: command ['dmesg'] failed with exit code 1: dmesg: read 
kernel buffer failed: Operation not permitted
Date: Tue Sep 17 19:20:29 2019
Lspci: Error: [Errno 2] No such file or directory: 'lspci': 'lspci'
Lsusb: Error: [Errno 2] No such file or directory: 'lsusb': 'lsusb'
MachineType: Gigabyte Technology Co., Ltd. GA-890GPA-UD3H
PackageArchitecture: all
PciMultimedia:
 
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-62-generic 
root=/dev/mapper/hex--vg-root ro splash quiet vt.handoff=1
SourcePackage: linux
UdevDb: Error: [Errno 2] No such file or directory: 'udevadm': 'udevadm'
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 11/24/2010
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: FF
dmi.board.name: GA-890GPA-UD3H
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: 
dmi:bvnAwardSoftwareInternational,Inc.:bvrFF:bd11/24/2010:svnGigabyteTechnologyCo.,Ltd.:pnGA-890GPA-UD3H:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-890GPA-UD3H:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: GA-890GPA-UD3H
dmi.sys.vendor: Gigabyte Technology Co., Ltd.

** Affects: linux (Ubuntu)
     Importance: Undecided
         Status: Incomplete


** Tags: amd64 apport-bug bionic

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https://bugs.launchpad.net/bugs/1844443

Title:
  Version check wrapper scripts for e.g. perf packaged in linux-tools-
  common prevent usage in a Docker container e.g. on Kubernetes

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  The `perf` profiling tool, and a few other tools, are part of the
  Linux project. Ubuntu gets them from a package specific to the running
  kernel version, and uses wrapper scripts installed as e.g.
  /usr/bin/perf to dispatch to the appropriate version for the running
  kernel. This appears to involve not only checking the actual kernel
  version number (e.g. 4.15.0) but also the patch level/build number and
  flavor that Ubuntu adds (e.g. 4.15.0-62-generic) if found in the
  kernel version.

  This is perfectly fine on a real system, where Ubuntu's package
  manager is actually in control of the kernel. But Ubuntu is also
  fantastically popular as a base for Docker images, and in a Docker
  container you have to take your lumps and run on whatever kernel
  version the host happens to be using, even if the host isn't using an
  official Ubuntu kernel, or running Ubuntu at all.

  As currently designed, the linux-tools-common wrapper scripts cannot
  work reliably in a Docker environment.

  When running in my particular Kubernetes environment (where the host
  is some kind of Red Hat Enterprise Linux derivative), this problem
  manifests as the following exchange:

  root@adamnovak-pod:/vg# perf record ls
  WARNING: perf not found for kernel 3.10.0

    You may need to install the following packages for this specific kernel:
      linux-tools-3.10.0

    You may also want to install one of the following packages to keep up to 
date:
      linux-tools
  root@adamnovak-pod:/vg# apt install linux-tools-3.10.0
  Reading package lists... Done
  Building dependency tree       
  Reading state information... Done
  E: Unable to locate package linux-tools-3.10.0
  E: Couldn't find any package by glob 'linux-tools-3.10.0'
  E: Couldn't find any package by regex 'linux-tools-3.10.0'

  However, the perf binary I happen to have installed, when I get it to
  try to run, at least appears to work, despite the kernel version
  mismatch. In larger tests, I've gotten perfectly fine profiling data.

  root@adamnovak-pod:/vg# /usr/lib/linux-tools/4.15.0-62-generic/perf record ls
  bin  deps  perf.data  scripts
  [ perf record: Woken up 2 times to write data ]
  [ perf record: Captured and wrote 0.002 MB perf.data (10 samples) ]
  root@adamnovak-pod:/vg# 

  So it is not clear that the level of specificity enforced by the
  wrapper scripts is actually necessary.

  There are a few potential solutions I can see to this problem:

  1. Modify the scripts to treat the lack of the exact right tool
  version being installed as a warning instead of an error, and have
  them select the closest version to run instead.

  2. Create linux-tools-3.10.0 ish through linux-tools-5.x.x packages,
  containing builds of perf and co. derived from those official mainline
  kernels, and a metapackage to install all of them. Then the package
  that you get prompted to install when running in a container will
  exist, and you will be able to install it to have a toolset that has a
  high probability of being compatible with the kernel you are running
  on. A container that needs to be portable between different hosts can
  install the metapackage.

  3. Create a package that conflicts with linux-tools-common and
  provides some arbitrary version of the tools. People who want a
  toolset that can run in a container can install that package instead,
  and bear the responsibility for what happens if the tools provided
  don't work with the kernel that happens to be running.

  4. Hook into the alternatives system; allow the user to switch between
  packages providing the tools for different kernel versions, with the
  default being the dispatch script.

  The workaround I am currently using is running this as soon as I get
  inside the container, to clobber the wrapper script with whatever
  actual binary I have installed:

  cp /usr/lib/linux-tools/*/perf /usr/bin/perf

  However, this is a pretty terrible hack.

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: linux-tools-common 4.15.0-62.69
  ProcVersionSignature: Ubuntu 4.15.0-62.69-generic 4.15.18
  Uname: Linux 4.15.0-62-generic x86_64
  AlsaDevices: Error: command ['ls', '-l', '/dev/snd/'] failed with exit code 
2: ls: cannot access '/dev/snd/': No such file or directory
  AplayDevices: Error: [Errno 2] No such file or directory: 'aplay': 'aplay'
  ApportVersion: 2.20.9-0ubuntu7.7
  Architecture: amd64
  ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord': 
'arecord'
  AudioDevicesInUse: Error: [Errno 2] No such file or directory: 'fuser': 
'fuser'
  CurrentDmesg: Error: command ['dmesg'] failed with exit code 1: dmesg: read 
kernel buffer failed: Operation not permitted
  Date: Tue Sep 17 19:20:29 2019
  Lspci: Error: [Errno 2] No such file or directory: 'lspci': 'lspci'
  Lsusb: Error: [Errno 2] No such file or directory: 'lsusb': 'lsusb'
  MachineType: Gigabyte Technology Co., Ltd. GA-890GPA-UD3H
  PackageArchitecture: all
  PciMultimedia:
   
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
  ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-4.15.0-62-generic 
root=/dev/mapper/hex--vg-root ro splash quiet vt.handoff=1
  SourcePackage: linux
  UdevDb: Error: [Errno 2] No such file or directory: 'udevadm': 'udevadm'
  UpgradeStatus: No upgrade log present (probably fresh install)
  dmi.bios.date: 11/24/2010
  dmi.bios.vendor: Award Software International, Inc.
  dmi.bios.version: FF
  dmi.board.name: GA-890GPA-UD3H
  dmi.board.vendor: Gigabyte Technology Co., Ltd.
  dmi.board.version: x.x
  dmi.chassis.type: 3
  dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
  dmi.modalias: 
dmi:bvnAwardSoftwareInternational,Inc.:bvrFF:bd11/24/2010:svnGigabyteTechnologyCo.,Ltd.:pnGA-890GPA-UD3H:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnGA-890GPA-UD3H:rvrx.x:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
  dmi.product.name: GA-890GPA-UD3H
  dmi.sys.vendor: Gigabyte Technology Co., Ltd.

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