passt, branch 2023_02_27.c538ee8

util: Add own prototype for __clone2() on ia64

2023-02-27T17:56:37+00:00

ia64 needs to use __clone2() as clone() is not available, but glibc
doesn't export the prototype. Take it from clone(2) to avoid an
implicit declaration:

util.c: In function ‘do_clone’:
util.c:512:16: warning: implicit declaration of function ‘__clone2’ [-Wimplicit-function-declaration]
  512 |         return __clone2(fn, stack_area + stack_size / 2, stack_size / 2,
      |                ^~~~~~~~

Signed-off-by: Stefano Brivio

contrib/apparmor: Split profile into abstractions, use them

2023-02-27T17:56:32+00:00

One day, libvirt might actually support running passt to provide
guest connectivity. Should libvirtd (or virtqemud) start passt, it
will need to access socket and PID files in specific locations, and
passt needs to accept SIGTERM in case QEMU fails to start after passt
is already started.

To make this more convenient, split the current profile into two
abstractions, for passt and for pasta, so that external programmes
can include the bits they need (and especially not include the pasta
abstraction if they only need to start passt), plus whatever specific
adaptation is needed.

For stand-alone usage of passt and pasta, the 'passt' profile simply
includes both abstractions, plus rules to create and access PID and
capture files in default or reasonable ($HOME) locations.

Tested on Debian with libvirt 9.0.0 together with a local fix to start
passt as intended, namely libvirt commit c0efdbdb9f66 ("qemu_passt:
Avoid double daemonizing passt"). This is an example of how the
libvirtd profile (or virtqemud abstraction, or virtqemud profile) can
use this:

  # support for passt network back-end
  /usr/bin/passt Cx -> passt,
  profile passt {
    /usr/bin/passt r,

    owner @{run}/user/[0-9]*/libvirt/qemu/run/passt/* rw,
    signal (receive) set=("term") peer=/usr/sbin/libvirtd,
    signal (receive) set=("term") peer=libvirtd,

    include if exists 
  }

translated:

- when executing /usr/bin/passt, switch to the subprofile "passt"
  (not the "discrete", i.e. stand-alone profile), described below.
  Scrub the environment (e.g. LD_PRELOAD is dropped)

- in the "passt" subprofile:

  - allow reading the binary

  - allow read and write access to PID and socket files

  - make passt accept SIGTERM from /usr/sbin/libvirtd, and
    libvirtd peer names

  - include anything else that's needed by passt itself

Suggested-by: Andrea Bolognani 
Signed-off-by: Stefano Brivio

qrap: Generate -netdev as JSON

2023-02-27T17:56:29+00:00

While generating -device as JSON when JSON is in use is
mandatory, because not doing so can often prevent the VM from
starting up, using JSON for -netdev simply makes things a bit
nicer. No reason not to do it, though.

Signed-off-by: Andrea Bolognani 
Reviewed-by: David Gibson

qrap: Introduce machine-specific PCI address base

2023-02-27T17:56:24+00:00

For pc machines, devices are placed directly on pci.0 with
addresses like

  bus=pci.0,addr=0xa

and in this case the existing code works correctly.

For q35 machines, however, a separate PCI bus is created for
each devices using a pcie-root-port, and the resulting
addresses look like

  bus=pci.9,addr=0x0

In this case, we need to treat PCI addresses as decimal, not
hexadecimal, both when parsing and generating them.

This issue has gone unnoticed for a long time because it only
shows up when enough PCI devices are present: for small
numbers, decimal and hexadecimal overlap, masking the issue.

Reported-by: Alona Paz 
Fixes: 5307faa05997 ("qrap: Strip network devices from command line, set them up according to machine")
Signed-off-by: Andrea Bolognani 
Reviewed-by: David Gibson

qrap: Drop args in JSON format

2023-02-27T17:56:22+00:00

When JSON support was introduced, the drop_args array has
not been updated accordingly.

Fixes: b944ca185587 ("qrap: Support JSON syntax for -device")
Signed-off-by: Andrea Bolognani 
Reviewed-by: David Gibson

qrap: Fix support for pc machines

2023-02-27T17:56:20+00:00

The JSON version of the template is incorrect, making qrap
completely unusable when JSON arguments are used together
with the pc machine type.

Fixes: b944ca185587 ("qrap: Support JSON syntax for -device")
Signed-off-by: Andrea Bolognani 
Reviewed-by: David Gibson

qrap: Fix limits for PCI addresses

2023-02-27T17:56:07+00:00

The pci.0 bus on a pc machine has 32 slots.

For q35 machines, we don't expect devices to be plugged into
pcie.0 directly, so technically we could have a very large
number of slots by adding many pcie-root-ports, but even in
this scenario 32 is a reasonable number.

Signed-off-by: Andrea Bolognani 
Reviewed-by: David Gibson

log, conf, tap: Define die() as err() plus exit(), drop cppcheck workarounds

2023-02-27T17:55:57+00:00

If we define die() as a variadic macro, passing __VA_ARGS__ to err(),
and calling exit() outside err() itself, we can drop the workarounds
introduced in commit 36f0199f6ef4 ("conf, tap: Silence two false
positive invalidFunctionArg from cppcheck").

Suggested-by: David Gibson 
Signed-off-by: Stefano Brivio 
Reviewed-by: David Gibson

doc/demo: Fix and suppress ShellCheck warnings

2023-02-27T17:55:39+00:00

ShellCheck reports (SC2034) that __qemu_arch is not used. Use it,
and silence the resulting SC2086 warning as we want word splitting on
options we pass with it.

While at it, silence SC2317 warnings for commands in cleanup() that
appear to be unreachable: cleanup() is only called as trap.

Signed-off-by: Stefano Brivio 
Reviewed-by: David Gibson

Fix definitions of SOCKET_MAX, TCP_MAX_CONNS

2023-02-27T17:55:31+00:00

...and, given that I keep getting this wrong, add a convenience
macro, MAX_FROM_BITS().

Signed-off-by: Stefano Brivio 
Reviewed-by: David Gibson