In commit bb71846325 we added some macro magic to avoid
variable-shadowing when using some of our more complicated
macros. One of the internal components of this is a macro
named MAKE_IDENTFIER. Fix the typo in its name: it should
be MAKE_IDENTIFIER.
Commit created with
sed -i -e 's/MAKE_IDENTFIER/MAKE_IDENTIFIER/g' include/qemu/*.h include/qapi/qmp/qobject.h
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20240801102516.3843780-1-peter.maydell@linaro.org
The typeof_strip_qual() is most useful for the atomic fetch-and-modify
operations in atomic.h, but it can be used elsewhere as well. For example,
QAPI_LIST_LENGTH() assumes that the argument is not const, which is not a
requirement.
Move the macro to compiler.h and, while at it, move it under #ifndef
__cplusplus to emphasize that it uses C-only constructs. A C++ version
of typeof_strip_qual() using type traits is possible[1], but beyond the
scope of this patch because the little C++ code that is in QEMU does not
use QAPI.
The patch was tested by changing the declaration of strv_from_str_list()
in qapi/qapi-type-helpers.c to:
char **strv_from_str_list(const strList *const list)
This is valid C code, and it fails to compile without this change.
[1] https://lore.kernel.org/qemu-devel/20240624205647.112034-1-flwu@google.com/
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Tested-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Using -fsanitize=undefined with Clang v18 causes an error if function
pointers are casted:
qapi/qapi-clone-visitor.c:188:5: runtime error: call to function visit_type_SocketAddress through pointer to incorrect function type 'bool (*)(struct Visitor *, const char *, void **, struct Error **)'
/tmp/qemu-ubsan/qapi/qapi-visit-sockets.c:487: note: visit_type_SocketAddress defined here
#0 0x5642aa2f7f3b in qapi_clone qapi/qapi-clone-visitor.c:188:5
#1 0x5642aa2c8ce5 in qio_channel_socket_listen_async io/channel-socket.c:285:18
#2 0x5642aa2b8903 in test_io_channel_setup_async tests/unit/test-io-channel-socket.c:116:5
#3 0x5642aa2b8204 in test_io_channel tests/unit/test-io-channel-socket.c:179:9
#4 0x5642aa2b8129 in test_io_channel_ipv4 tests/unit/test-io-channel-socket.c:323:5
...
It also prevents enabling the strict mode of CFI which is currently
disabled with -fsanitize-cfi-icall-generalize-pointers.
The problematic casts are necessary to pass visit_type_T() and
visit_type_T_members() as callbacks to qapi_clone() and qapi_clone_members(),
respectively. Open-code these two functions to avoid the callbacks, and
thus the type casts.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2346
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240524-xkb-v4-3-2de564e5c859@daynix.com>
[thuth: Improve commit message according to Markus' suggestions]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Manual change. Remove the definition in
include/qapi/qmp/qerror.h.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-11-armbru@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Mechanical transformation using sed, manually
removing the definition in include/qapi/qmp/qerror.h.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-10-armbru@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
[Straightforward conflict with commit aeaafb1e59 (migration: export
migration_is_running) resolved]
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Manual changes (escaping the format in qapi/visit.py).
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-8-armbru@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Mechanical transformation using:
$ sed -i -e "s/QERR_INVALID_PARAMETER,/\"Invalid parameter '%s'\",/" \
$(git grep -lw QERR_INVALID_PARAMETER)
Manually simplify qemu_opts_create(), and remove the macro definition
in include/qapi/qmp/qerror.h.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-6-armbru@redhat.com>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Mechanical transformation using sed, and manual cleanup.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-5-armbru@redhat.com>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Mechanical transformation using sed, and manual cleanup.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-4-armbru@redhat.com>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Mechanical transformation using sed, and manual cleanup.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-3-armbru@redhat.com>
The error_vprepend() should use ERRP_GUARD() just as the documentation
of ERRP_GUARD() says:
> It must be used when the function dereferences @errp or passes
> @errp to error_prepend(), error_vprepend(), or error_append_hint().
Considering that error_vprepend() is also an API provided in error.h,
it is necessary to add it to the description of the rules for using
ERRP_GUARD().
Cc: Markus Armbruster <armbru@redhat.com>
Cc: Michael Roth <michael.roth@amd.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240311033822.3142585-2-zhao1.liu@linux.intel.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Conversion of docs/devel/qapi-code-gen.txt to ReST left several
dangling references behind. Fix them to point to
docs/devel/qapi-code-gen.rst.
Fixes: f7aa076dbd (docs: convert qapi-code-gen.txt to ReST)
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240120095327.666239-4-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
StringOutputVisitor crashes when it visits a struct because
->start_struct() is NULL.
Show "<omitted>" instead of crashing. This is necessary because the
virtio-blk-pci iothread-vq-mapping parameter that I'd like to introduce
soon is a list of IOThreadMapping structs.
This patch is a quick fix to solve the crash, but the long-term solution
is replacing StringOutputVisitor with something that can handle the full
gamut of values in QEMU.
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20231212134934.500289-1-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Variables declared in macros can shadow other variables. Much of the
time, this is harmless, e.g.:
#define _FDT(exp) \
do { \
int ret = (exp); \
if (ret < 0) { \
error_report("error creating device tree: %s: %s", \
#exp, fdt_strerror(ret)); \
exit(1); \
} \
} while (0)
Harmless shadowing in h_client_architecture_support():
target_ulong ret;
[...]
ret = do_client_architecture_support(cpu, spapr, vec, fdt_bufsize);
if (ret == H_SUCCESS) {
_FDT((fdt_pack(spapr->fdt_blob)));
[...]
}
return ret;
However, we can get in trouble when the shadowed variable is used in a
macro argument:
#define QOBJECT(obj) ({ \
typeof(obj) o = (obj); \
o ? container_of(&(o)->base, QObject, base) : NULL; \
})
QOBJECT(o) expands into
({
---> typeof(o) o = (o);
o ? container_of(&(o)->base, QObject, base) : NULL;
})
Unintended variable name capture at --->. We'd be saved by
-Winit-self. But I could certainly construct more elaborate death
traps that don't trigger it.
To reduce the risk of trapping ourselves, we use variable names in
macros that no sane person would use elsewhere. Here's our actual
definition of QOBJECT():
#define QOBJECT(obj) ({ \
typeof(obj) _obj = (obj); \
_obj ? container_of(&(_obj)->base, QObject, base) : NULL; \
})
Works well enough until we nest macro calls. For instance, with
#define qobject_ref(obj) ({ \
typeof(obj) _obj = (obj); \
qobject_ref_impl(QOBJECT(_obj)); \
_obj; \
})
the expression qobject_ref(obj) expands into
({
typeof(obj) _obj = (obj);
qobject_ref_impl(
({
---> typeof(_obj) _obj = (_obj);
_obj ? container_of(&(_obj)->base, QObject, base) : NULL;
}));
_obj;
})
Unintended variable name capture at --->.
The only reliable way to prevent unintended variable name capture is
-Wshadow.
One blocker for enabling it is shadowing hiding in function-like
macros like
qdict_put(dict, "name", qobject_ref(...))
qdict_put() wraps its last argument in QOBJECT(), and the last
argument here contains another QOBJECT().
Use dark preprocessor sorcery to make the macros that give us this
problem use different variable names on every call.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-ID: <20230921121312.1301864-8-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
There should be no paths from a coroutine_fn to aio_poll, however in
practice coroutine_mixed_fn will call aio_poll in the !qemu_in_coroutine()
path. By marking mixed functions, we can track accurately the call paths
that execute entirely in coroutine context, and find more missing
coroutine_fn markers. This results in more accurate checks that
coroutine code does not end up blocking.
If the marking were extended transitively to all functions that call
these ones, static analysis could be done much more efficiently.
However, this is a start and makes it possible to use vrc's path-based
searches to find potential bugs where coroutine_fns call blocking functions.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The QERR_ macros are leftovers from the days of "rich" error objects.
We've been trying to reduce their remaining use.
The stubbed out Rocker monitor commands are the last remaining users
of QERR_FEATURE_DISABLED. They fail like this:
(qemu) info rocker mumble
Error: The feature 'rocker' is not enabled
The real rocker commands fail like this when the named object doesn't
exist:
Error: rocker mumble not found
If that's good enough when Rocker is enabled, then it's good enough
when it's disabled, so replace QERR_FEATURE_DISABLED with that, and
drop the macro.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230207075115.1525-13-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
replay_add_blocker() takes an Error *. All callers pass one created
like this:
error_setg(&blocker, QERR_REPLAY_NOT_SUPPORTED, "some feature");
Folding this into replay_add_blocker() simplifies the callers, losing
a bit of generality we haven't needed in more than six years.
Since there are no other uses of macro QERR_REPLAY_NOT_SUPPORTED,
replace the remaining one by its expansion, and drop the macro.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230207075115.1525-10-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
