[v2,for-5.2,0/6] Deprecate or forbid crazy QemuOpts cases

Message

Paolo Bonzini Nov. 9, 2020, 1:39 p.m. UTC

It's very hard to make QemuOpts fail.  It's also very easy
to write command lines that QemuOpts accept but make no sense.

This series deals with three cases:

- QemuOpts accepts ids even for options that are meant to be singletons.
As a result, a command line option like "-M q35,id=ff" is ignored silently.

- QemuOpts simply matches "help" or "?" against the option name to
determine whether the user asked for help.  Something like "nohelp" or
"?=please" will print the help message.

- QemuOpts lets you write boolean options in "short form" where "abc"
means "abc=on" and "noabc" means "abc=off".  This is confusing, since it
is not done for the first key=value pair (but only if there is an implied
key); it can also be grossly misused, as in the previous example, because
it is not type safe.  In case you need confirmation, "-device e1000,noid"
will create a device with id equal to "off".

Unfortunately, this last idiom has found wide use with -chardev (think
"server,nowait") and to a lesser extent -spice, so it can only be
deprecated.  The other two are removed.

Patches 1-3 are cleanups.  Patches 4-6 deal with the above issues one
by one.  I have a seventh patch to remove the third argument to
qemu_opts_create, but it touches a few dozen files.

Paolo

Supersedes: <[e-mail]>

Paolo Bonzini (6):
  qemu-option: simplify search for end of key
  qemu-option: pass QemuOptsList to opts_accepts_any
  qemu-option: restrict qemu_opts_set to merge-lists QemuOpts
  qemu-option: clean up id vs. list->merge_lists
  qemu-option: move help handling to get_opt_name_value
  qemu-option: warn for short-form boolean options

 docs/system/deprecated.rst |   6 ++
 include/qemu/option.h      |   3 +-
 softmmu/vl.c               |  19 ++---
 tests/test-qemu-opts.c     |  26 ++++++-
 util/qemu-option.c         | 149 +++++++++++++++++++------------------
 5 files changed, 113 insertions(+), 90 deletions(-)

Comments

[e-mail] Nov. 9, 2020, 1:54 p.m. UTC | #1

Patchew URL: https://patchew.org/QEMU/[e-mail]/



Hi,

This series seems to have some coding style problems. See output below for
more information:

Message-id: [e-mail]
Subject: [PATCH v2 for-5.2 0/6] Deprecate or forbid crazy QemuOpts cases
Type: series

=== TEST SCRIPT BEGIN ===
#!/bin/bash
git rev-parse base > /dev/null || exit 0
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback base..
=== TEST SCRIPT END ===

Updating 3c8cf5a9c21ff8782164d1def7f44bd888713384
From https://github.com/patchew-project/qemu
 - [tag update]      patchew/[e-mail] -> patchew/[e-mail]
 - [tag update]      patchew/[e-mail] -> patchew/[e-mail]
 - [tag update]      patchew/[e-mail] -> patchew/[e-mail]
 - [tag update]      patchew/[e-mail] -> patchew/[e-mail]
 * [new tag]         patchew/[e-mail] -> patchew/[e-mail]
 - [tag update]      patchew/[e-mail] -> patchew/[e-mail]
Switched to a new branch 'test'
50c88b8 qemu-option: warn for short-form boolean options
5ab2220 qemu-option: move help handling to get_opt_name_value
fc2619d qemu-option: clean up id vs. list->merge_lists
e17617f qemu-option: restrict qemu_opts_set to merge-lists QemuOpts
7739f06 qemu-option: pass QemuOptsList to opts_accepts_any
c1676e5 qemu-option: simplify search for end of key

=== OUTPUT BEGIN ===
1/6 Checking commit c1676e514286 (qemu-option: simplify search for end of key)
2/6 Checking commit 7739f060c567 (qemu-option: pass QemuOptsList to opts_accepts_any)
3/6 Checking commit e17617fd5081 (qemu-option: restrict qemu_opts_set to merge-lists QemuOpts)
WARNING: line over 80 characters
#32: FILE: include/qemu/option.h:122:
+bool qemu_opts_set(QemuOptsList *list, const char *name, const char *value, Error **errp);

WARNING: line over 80 characters
#46: FILE: softmmu/vl.c:3110:
+                qemu_opts_set(qemu_find_opts("machine"), "kernel", optarg, &error_abort);

WARNING: line over 80 characters
#51: FILE: softmmu/vl.c:3113:
+                qemu_opts_set(qemu_find_opts("machine"), "initrd", optarg, &error_abort);

WARNING: line over 80 characters
#56: FILE: softmmu/vl.c:3116:
+                qemu_opts_set(qemu_find_opts("machine"), "append", optarg, &error_abort);

WARNING: line over 80 characters
#61: FILE: softmmu/vl.c:3119:
+                qemu_opts_set(qemu_find_opts("machine"), "dtb", optarg, &error_abort);

ERROR: line over 90 characters
#71: FILE: softmmu/vl.c:3229:
+                qemu_opts_set(qemu_find_opts("machine"), "firmware", optarg, &error_abort);

WARNING: line over 80 characters
#152: FILE: util/qemu-option.c:684:
+bool qemu_opts_set(QemuOptsList *list, const char *name, const char *value, Error **errp)

total: 1 errors, 6 warnings, 120 lines checked

Patch 3/6 has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.

4/6 Checking commit fc2619d6e44c (qemu-option: clean up id vs. list->merge_lists)
5/6 Checking commit 5ab2220302ba (qemu-option: move help handling to get_opt_name_value)
6/6 Checking commit 50c88b8f7929 (qemu-option: warn for short-form boolean options)
WARNING: line over 80 characters
#81: FILE: util/qemu-option.c:803:
+                warn_report("short-form boolean option '%s%s' deprecated", prefix, *name);

WARNING: line over 80 characters
#100: FILE: util/qemu-option.c:834:
+        p = get_opt_name_value(p, firstname, warn_on_flag, help_wanted, &option, &value);

total: 0 errors, 2 warnings, 127 lines checked

Patch 6/6 has style problems, please review.  If any of these errors
are false positives report them to the maintainer, see
CHECKPATCH in MAINTAINERS.
=== OUTPUT END ===

Test command exited with code: 1


The full log is available at
http://patchew.org/logs/[e-mail]/testing.checkpatch/?type=message.
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