[PATCH v4 0/3] improve error handling for module load

[Claudio Fontana]

CHANGELOG:

v3 -> v4: (Richard)

* module_object_class_by_name: return NULL immediately on load error.
* audio_driver_lookup: same.
* bdrv_find_format: same.

* dmg_open: handle optional compression submodules better: f.e.,
  if "dmg-bz2" is not present, continue but offer a warning.
  If "dmg-bz2" load fails with error, error out and return.

* module_load_dso: add newline to error_append_hint.

v2 -> v3:

* take the file existence check outside of module_load_file,
  rename module_load_file to module_load_dso, will be called only on
  an existing file. This will simplify the return value. (Richard)

* move exported function documentation into header files (Richard)

v1 -> v2:

* do not treat the display help text any differently and do report
  module load _errors_. If the module does not exist (ENOENT, ENOTDIR),
  no error will be produced.

DESCRIPTION:

while investigating a permission issue in accel, where accel-tcg-x86_64.so
was not accessible, I noticed that no errors were produced regarding the
module load failure.

This series attempts to improve module_load_one and module_load_qom_one
to handle the error cases better and produce some errors.

Patch 1 is already reviewed and is about removing an unused existing
argument "mayfail" from the call stack.

Patch 2 is the real meat, and that one I would say is RFC.
Will follow up with comments on the specific questions I have.

Patch 3 finally adds a simple check in accel/, aborting if a module
is not found, but relying on the existing error report from
module_load_qom_one.

Claudio Fontana (3):
  module: removed unused function argument "mayfail"
  module: add Error arguments to module_load_one and module_load_qom_one
  accel: abort if we fail to load the accelerator plugin

 accel/accel-softmmu.c |   8 ++-
 audio/audio.c         |   9 ++-
 block.c               |  15 ++++-
 block/dmg.c           |  18 +++++-
 hw/core/qdev.c        |  10 ++-
 include/qemu/module.h |  38 +++++++++--
 qom/object.c          |  18 +++++-
 softmmu/qtest.c       |   6 +-
 ui/console.c          |  18 +++++-
 util/module.c         | 142 ++++++++++++++++++++++++------------------
 10 files changed, 201 insertions(+), 81 deletions(-)

-- 
2.26.2