[PULL 00/12] Misc bugfix patches (+ improved module errors) for QEMU 7.2

[PULL 00/12] Misc bugfix patches (+ improved module errors) for QEMU 7.2

[Paolo Bonzini]

The following changes since commit 6295a58ad1b73985b9c32d184de7d2ed1fbe1774:

  Merge tag 'pull-target-arm-20221104' of https://git.linaro.org/people/pmaydell/qemu-arm into staging (2022-11-04 11:01:17 -0400)

are available in the Git repository at:

  https://gitlab.com/bonzini/qemu.git tags/for-upstream

for you to fetch changes up to 5141e9a23fc9a890d66a5700920a5ffd8885121f:

  accel: abort if we fail to load the accelerator plugin (2022-11-06 09:48:50 +0100)

----------------------------------------------------------------
* bug fixes for Win32 event loop
* bug fixes for -Wextra
* fix gdb XML for 32-bit x86
* improve error handling for module load
----------------------------------------------------------------

Kevin's patch below is a bugfix that Claudio picked up, and became part of
his series to improve error reporting for modules.

Thanks,

Paolo

Bin Meng (3):
      util/main-loop: Fix maximum number of wait objects for win32
      util/main-loop: Avoid adding the same HANDLE twice
      util/aio-win32: Correct the event array size in aio_poll()

Claudio Fontana (4):
      module: removed unused function argument "mayfail"
      module: rename module_load_one to module_load
      module: add Error arguments to module_load and module_load_qom
      accel: abort if we fail to load the accelerator plugin

Kevin Wolf (1):
      dmg: warn when opening dmg images containing blocks of unknown type

Paolo Bonzini (1):
      meson: avoid unused arguments of main() in compiler tests

Stefan Weil (2):
      Fix broken configure with -Wunused-parameter
      Add missing include statement for global xml_builtin

TaiseiIto (1):
      gdb-xml: Fix size of EFER register on i386 architecture when debugged by GDB

 accel/accel-softmmu.c    |   8 +-
 audio/audio.c            |  16 ++--
 block.c                  |  20 +++--
 block/dmg.c              |  33 +++++++-
 configure                |   8 +-
 gdb-xml/i386-32bit.xml   |   2 +-
 hw/core/qdev.c           |  17 +++-
 include/qemu/main-loop.h |   2 +
 include/qemu/module.h    |  37 +++++++--
 meson.build              |   8 +-
 qom/object.c             |  18 +++-
 scripts/feature_to_c.sh  |   1 +
 softmmu/qtest.c          |   8 +-
 ui/console.c             |  18 +++-
 util/aio-win32.c         |   5 +-
 util/main-loop.c         |  20 +++--
 util/module.c            | 211 ++++++++++++++++++++++++++---------------------
 17 files changed, 290 insertions(+), 142 deletions(-)
-- 
2.38.1

[PULL 01/12] util/main-loop: Fix maximum number of wait objects for win32

[Paolo Bonzini]

From: Bin Meng <bin.meng@windriver.com>

The maximum number of wait objects for win32 should be
MAXIMUM_WAIT_OBJECTS, not MAXIMUM_WAIT_OBJECTS + 1.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Message-Id: <20221019102015.2441622-1-bmeng.cn@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 util/main-loop.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/util/main-loop.c b/util/main-loop.c
index f00a25451bdc..de38876064e4 100644
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -363,10 +363,10 @@ void qemu_del_polling_cb(PollingFunc *func, void *opaque)
 /* Wait objects support */
 typedef struct WaitObjects {
     int num;
-    int revents[MAXIMUM_WAIT_OBJECTS + 1];
-    HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
-    WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS + 1];
-    void *opaque[MAXIMUM_WAIT_OBJECTS + 1];
+    int revents[MAXIMUM_WAIT_OBJECTS];
+    HANDLE events[MAXIMUM_WAIT_OBJECTS];
+    WaitObjectFunc *func[MAXIMUM_WAIT_OBJECTS];
+    void *opaque[MAXIMUM_WAIT_OBJECTS];
 } WaitObjects;
 
 static WaitObjects wait_objects = {0};
@@ -395,7 +395,7 @@ void qemu_del_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
         if (w->events[i] == handle) {
             found = 1;
         }
-        if (found) {
+        if (found && i < (MAXIMUM_WAIT_OBJECTS - 1)) {
             w->events[i] = w->events[i + 1];
             w->func[i] = w->func[i + 1];
             w->opaque[i] = w->opaque[i + 1];
-- 
2.38.1

[PULL 02/12] util/main-loop: Avoid adding the same HANDLE twice

[Paolo Bonzini]

From: Bin Meng <bin.meng@windriver.com>

Fix the logic in qemu_add_wait_object() to avoid adding the same
HANDLE twice, as the behavior is undefined when passing an array
that contains same HANDLEs to WaitForMultipleObjects() API.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Message-Id: <20221019102015.2441622-2-bmeng.cn@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 include/qemu/main-loop.h |  2 ++
 util/main-loop.c         | 10 ++++++++++
 2 files changed, 12 insertions(+)

diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h
index aac707d073a1..3c9a9a982def 100644
--- a/include/qemu/main-loop.h
+++ b/include/qemu/main-loop.h
@@ -157,6 +157,8 @@ typedef void WaitObjectFunc(void *opaque);
  * in the main loop's calls to WaitForMultipleObjects.  When the handle
  * is in a signaled state, QEMU will call @func.
  *
+ * If the same HANDLE is added twice, this function returns -1.
+ *
  * @handle: The Windows handle to be observed.
  * @func: A function to be called when @handle is in a signaled state.
  * @opaque: A pointer-size value that is passed to @func.
diff --git a/util/main-loop.c b/util/main-loop.c
index de38876064e4..10fa74c6e319 100644
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -373,10 +373,20 @@ static WaitObjects wait_objects = {0};
 
 int qemu_add_wait_object(HANDLE handle, WaitObjectFunc *func, void *opaque)
 {
+    int i;
     WaitObjects *w = &wait_objects;
+
     if (w->num >= MAXIMUM_WAIT_OBJECTS) {
         return -1;
     }
+
+    for (i = 0; i < w->num; i++) {
+        /* check if the same handle is added twice */
+        if (w->events[i] == handle) {
+            return -1;
+        }
+    }
+
     w->events[w->num] = handle;
     w->func[w->num] = func;
     w->opaque[w->num] = opaque;
-- 
2.38.1

[PULL 03/12] util/aio-win32: Correct the event array size in aio_poll()

[Paolo Bonzini]

From: Bin Meng <bin.meng@windriver.com>

WaitForMultipleObjects() can only wait for MAXIMUM_WAIT_OBJECTS
object handles. Correct the event array size in aio_poll() and
add a assert() to ensure it does not cause out of bound access.

Signed-off-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221019102015.2441622-3-bmeng.cn@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 util/aio-win32.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/util/aio-win32.c b/util/aio-win32.c
index 44003d645ecd..80cfe012ad8f 100644
--- a/util/aio-win32.c
+++ b/util/aio-win32.c
@@ -326,9 +326,9 @@ void aio_dispatch(AioContext *ctx)
 bool aio_poll(AioContext *ctx, bool blocking)
 {
     AioHandler *node;
-    HANDLE events[MAXIMUM_WAIT_OBJECTS + 1];
+    HANDLE events[MAXIMUM_WAIT_OBJECTS];
     bool progress, have_select_revents, first;
-    int count;
+    unsigned count;
     int timeout;
 
     /*
@@ -369,6 +369,7 @@ bool aio_poll(AioContext *ctx, bool blocking)
     QLIST_FOREACH_RCU(node, &ctx->aio_handlers, node) {
         if (!node->deleted && node->io_notify
             && aio_node_check(ctx, node->is_external)) {
+            assert(count < MAXIMUM_WAIT_OBJECTS);
             events[count++] = event_notifier_get_handle(node->e);
         }
     }
-- 
2.38.1

[PULL 04/12] gdb-xml: Fix size of EFER register on i386 architecture when debugged by GDB

[Paolo Bonzini]

From: TaiseiIto <taisei1212@outlook.jp>

Before this commit, there were contradictory descriptions about size of EFER
register.
Line 113 says the size is 8 bytes.
Line 129 says the size is 4 bytes.

As a result, when GDB is debugging an OS running on QEMU, the GDB cannot
read 'g' packets correctly. This 'g' packet transmits values of each
registers of machine emulated by QEMU to GDB. QEMU, the packet sender,
assign 4 bytes for EFER in 'g' packet based on the line 113.
GDB, the packet receiver, extract 8 bytes for EFER in 'g' packet based on
the line 129. Therefore, all registers located behind EFER in 'g' packet
has been shifted 4 bytes in GDB.

After this commit, GDB can read 'g' packets correctly.

Signed-off-by: TaiseiIto <taisei1212@outlook.jp>
Message-Id: <TY0PR0101MB4285F637209075C9F65FCDA6A4479@TY0PR0101MB4285.apcprd01.prod.exchangelabs.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 gdb-xml/i386-32bit.xml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gdb-xml/i386-32bit.xml b/gdb-xml/i386-32bit.xml
index 872fcea9c25a..7a66a02b67e3 100644
--- a/gdb-xml/i386-32bit.xml
+++ b/gdb-xml/i386-32bit.xml
@@ -110,7 +110,7 @@
 	<field name="PKE" start="22" end="22"/>
   </flags>
 
-  <flags id="i386_efer" size="8">
+  <flags id="i386_efer" size="4">
 	<field name="TCE" start="15" end="15"/>
 	<field name="FFXSR" start="14" end="14"/>
 	<field name="LMSLE" start="13" end="13"/>
-- 
2.38.1

[PULL 05/12] Fix broken configure with -Wunused-parameter

[Paolo Bonzini]

From: Stefan Weil <sw@weilnetz.de>

The configure script fails because it tries to compile small C programs
with a main function which is declared with arguments argc and argv
although those arguments are unused.

Running `configure -extra-cflags=-Wunused-parameter` triggers the problem.
configure for a native build does abort but shows the error in config.log.
A cross build configure for Windows with Debian stable aborts with an
error.

Avoiding unused arguments fixes this.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Message-Id: <20221102202258.456359-1-sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 configure | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/configure b/configure
index 4275f5419fae..66928692b058 100755
--- a/configure
+++ b/configure
@@ -1258,7 +1258,7 @@ if test "$stack_protector" != "no"; then
   cat > $TMPC << EOF
 int main(int argc, char *argv[])
 {
-    char arr[64], *p = arr, *c = argv[0];
+    char arr[64], *p = arr, *c = argv[argc - 1];
     while (*c) {
         *p++ = *c++;
     }
@@ -1607,7 +1607,7 @@ fi
 
 if test "$safe_stack" = "yes"; then
 cat > $TMPC << EOF
-int main(int argc, char *argv[])
+int main(void)
 {
 #if ! __has_feature(safe_stack)
 #error SafeStack Disabled
@@ -1629,7 +1629,7 @@ EOF
   fi
 else
 cat > $TMPC << EOF
-int main(int argc, char *argv[])
+int main(void)
 {
 #if defined(__has_feature)
 #if __has_feature(safe_stack)
@@ -1675,7 +1675,7 @@ static const int Z = 1;
 #define TAUT(X) ((X) == Z)
 #define PAREN(X, Y) (X == Y)
 #define ID(X) (X)
-int main(int argc, char *argv[])
+int main(void)
 {
     int x = 0, y = 0;
     x = ID(x);
-- 
2.38.1

[PULL 06/12] meson: avoid unused arguments of main() in compiler tests

[Paolo Bonzini]

meson.build has one test where "main" is declared unnecessarily
with argc and argv arguments, but does not use them.  Because
the test needs -Werror too, HAVE_BROKEN_SIZE_MAX is defined
incorrectly.

Fix the test and, for consistency, remove argc and argv whenever
they are not needed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 meson.build | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/meson.build b/meson.build
index 1d448272ab88..cf3e517e56d8 100644
--- a/meson.build
+++ b/meson.build
@@ -2165,7 +2165,7 @@ config_host_data.set('CONFIG_SPLICE', cc.links(gnu_source_prefix + '''
 
 config_host_data.set('HAVE_MLOCKALL', cc.links(gnu_source_prefix + '''
   #include <sys/mman.h>
-  int main(int argc, char *argv[]) {
+  int main(void) {
     return mlockall(MCL_FUTURE);
   }'''))
 
@@ -2210,7 +2210,7 @@ config_host_data.set('HAVE_FSXATTR', cc.links('''
 config_host_data.set('HAVE_BROKEN_SIZE_MAX', not cc.compiles('''
     #include <stdint.h>
     #include <stdio.h>
-    int main(int argc, char *argv[]) {
+    int main(void) {
         return printf("%zu", SIZE_MAX);
     }''', args: ['-Werror']))
 
@@ -2327,7 +2327,7 @@ config_host_data.set('CONFIG_AVX2_OPT', get_option('avx2') \
       __m256i x = *(__m256i *)a;
       return _mm256_testz_si256(x, x);
     }
-    int main(int argc, char *argv[]) { return bar(argv[0]); }
+    int main(int argc, char *argv[]) { return bar(argv[argc - 1]); }
   '''), error_message: 'AVX2 not available').allowed())
 
 config_host_data.set('CONFIG_AVX512F_OPT', get_option('avx512f') \
@@ -2341,7 +2341,7 @@ config_host_data.set('CONFIG_AVX512F_OPT', get_option('avx512f') \
       __m512i x = *(__m512i *)a;
       return _mm512_test_epi64_mask(x, x);
     }
-    int main(int argc, char *argv[]) { return bar(argv[0]); }
+    int main(int argc, char *argv[]) { return bar(argv[argc - 1]); }
   '''), error_message: 'AVX512F not available').allowed())
 
 have_pvrdma = get_option('pvrdma') \
-- 
2.38.1

[PULL 07/12] Add missing include statement for global xml_builtin

[Paolo Bonzini]

From: Stefan Weil <sw@weilnetz.de>

This fixes some compiler warnings with compiler flag
-Wmissing-variable-declarations (tested with clang):

    aarch64_be-linux-user-gdbstub-xml.c:564:19: warning: no previous extern declaration for non-static variable 'xml_builtin' [-Wmissing-variable-declarations]
    aarch64-linux-user-gdbstub-xml.c:564:19: warning: no previous extern declaration for non-static variable 'xml_builtin' [-Wmissing-variable-declarations]
    aarch64-softmmu-gdbstub-xml.c:1763:19: warning: no previous extern declaration for non-static variable 'xml_builtin' [-Wmissing-variable-declarations]

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 scripts/feature_to_c.sh | 1 +
 1 file changed, 1 insertion(+)

diff --git a/scripts/feature_to_c.sh b/scripts/feature_to_c.sh
index b1169899c19d..c1f67c8f6a57 100644
--- a/scripts/feature_to_c.sh
+++ b/scripts/feature_to_c.sh
@@ -56,6 +56,7 @@ for input; do
 done
 
 echo
+echo '#include "exec/gdbstub.h"'
 echo "const char *const xml_builtin[][2] = {"
 
 for input; do
-- 
2.38.1

[PULL 08/12] module: removed unused function argument "mayfail"

[Paolo Bonzini]

From: Claudio Fontana <cfontana@suse.de>

mayfail is always passed as false for every invocation throughout the program.
It controls whether to printf or not to printf an error on
g_module_open failure.

Remove this unused argument.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220929093035.4231-2-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 include/qemu/module.h |  8 ++++----
 softmmu/qtest.c       |  2 +-
 util/module.c         | 20 +++++++++-----------
 3 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/include/qemu/module.h b/include/qemu/module.h
index bd73607104c9..8c012bbe038d 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -61,15 +61,15 @@ typedef enum {
 #define fuzz_target_init(function) module_init(function, \
                                                MODULE_INIT_FUZZ_TARGET)
 #define migration_init(function) module_init(function, MODULE_INIT_MIGRATION)
-#define block_module_load_one(lib) module_load_one("block-", lib, false)
-#define ui_module_load_one(lib) module_load_one("ui-", lib, false)
-#define audio_module_load_one(lib) module_load_one("audio-", lib, false)
+#define block_module_load_one(lib) module_load_one("block-", lib)
+#define ui_module_load_one(lib) module_load_one("ui-", lib)
+#define audio_module_load_one(lib) module_load_one("audio-", lib)
 
 void register_module_init(void (*fn)(void), module_init_type type);
 void register_dso_module_init(void (*fn)(void), module_init_type type);
 
 void module_call_init(module_init_type type);
-bool module_load_one(const char *prefix, const char *lib_name, bool mayfail);
+bool module_load_one(const char *prefix, const char *lib_name);
 void module_load_qom_one(const char *type);
 void module_load_qom_all(void);
 void module_allow_arch(const char *arch);
diff --git a/softmmu/qtest.c b/softmmu/qtest.c
index afea7693d0cd..ff74c5d7092e 100644
--- a/softmmu/qtest.c
+++ b/softmmu/qtest.c
@@ -756,7 +756,7 @@ static void qtest_process_command(CharBackend *chr, gchar **words)
         g_assert(words[1] && words[2]);
 
         qtest_send_prefix(chr);
-        if (module_load_one(words[1], words[2], false)) {
+        if (module_load_one(words[1], words[2])) {
             qtest_sendf(chr, "OK\n");
         } else {
             qtest_sendf(chr, "FAIL\n");
diff --git a/util/module.c b/util/module.c
index 8ddb0e18f517..8563edd6267c 100644
--- a/util/module.c
+++ b/util/module.c
@@ -144,7 +144,7 @@ static bool module_check_arch(const QemuModinfo *modinfo)
     return true;
 }
 
-static int module_load_file(const char *fname, bool mayfail, bool export_symbols)
+static int module_load_file(const char *fname, bool export_symbols)
 {
     GModule *g_module;
     void (*sym)(void);
@@ -172,10 +172,8 @@ static int module_load_file(const char *fname, bool mayfail, bool export_symbols
     }
     g_module = g_module_open(fname, flags);
     if (!g_module) {
-        if (!mayfail) {
-            fprintf(stderr, "Failed to open module: %s\n",
-                    g_module_error());
-        }
+        fprintf(stderr, "Failed to open module: %s\n",
+                g_module_error());
         ret = -EINVAL;
         goto out;
     }
@@ -208,7 +206,7 @@ out:
 }
 #endif
 
-bool module_load_one(const char *prefix, const char *lib_name, bool mayfail)
+bool module_load_one(const char *prefix, const char *lib_name)
 {
     bool success = false;
 
@@ -256,7 +254,7 @@ bool module_load_one(const char *prefix, const char *lib_name, bool mayfail)
             if (strcmp(modinfo->name, module_name) == 0) {
                 /* we depend on other module(s) */
                 for (sl = modinfo->deps; *sl != NULL; sl++) {
-                    module_load_one("", *sl, false);
+                    module_load_one("", *sl);
                 }
             } else {
                 for (sl = modinfo->deps; *sl != NULL; sl++) {
@@ -287,7 +285,7 @@ bool module_load_one(const char *prefix, const char *lib_name, bool mayfail)
     for (i = 0; i < n_dirs; i++) {
         fname = g_strdup_printf("%s/%s%s",
                 dirs[i], module_name, CONFIG_HOST_DSOSUF);
-        ret = module_load_file(fname, mayfail, export_symbols);
+        ret = module_load_file(fname, export_symbols);
         g_free(fname);
         fname = NULL;
         /* Try loading until loaded a module file */
@@ -333,7 +331,7 @@ void module_load_qom_one(const char *type)
         }
         for (sl = modinfo->objs; *sl != NULL; sl++) {
             if (strcmp(type, *sl) == 0) {
-                module_load_one("", modinfo->name, false);
+                module_load_one("", modinfo->name);
             }
         }
     }
@@ -354,7 +352,7 @@ void module_load_qom_all(void)
         if (!module_check_arch(modinfo)) {
             continue;
         }
-        module_load_one("", modinfo->name, false);
+        module_load_one("", modinfo->name);
     }
     module_loaded_qom_all = true;
 }
@@ -370,7 +368,7 @@ void qemu_load_module_for_opts(const char *group)
         }
         for (sl = modinfo->opts; *sl != NULL; sl++) {
             if (strcmp(group, *sl) == 0) {
-                module_load_one("", modinfo->name, false);
+                module_load_one("", modinfo->name);
             }
         }
     }
-- 
2.38.1

[PULL 09/12] module: rename module_load_one to module_load

[Paolo Bonzini]

From: Claudio Fontana <cfontana@suse.de>

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220929093035.4231-3-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 audio/audio.c         |  2 +-
 block.c               |  4 ++--
 block/dmg.c           |  4 ++--
 hw/core/qdev.c        |  2 +-
 include/qemu/module.h | 10 +++++-----
 qom/object.c          |  4 ++--
 softmmu/qtest.c       |  2 +-
 ui/console.c          |  6 +++---
 util/module.c         | 14 +++++++-------
 9 files changed, 24 insertions(+), 24 deletions(-)

diff --git a/audio/audio.c b/audio/audio.c
index cc664271ebb5..379f19dc891f 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -80,7 +80,7 @@ audio_driver *audio_driver_lookup(const char *name)
         }
     }
 
-    audio_module_load_one(name);
+    audio_module_load(name);
     QLIST_FOREACH(d, &audio_drivers, next) {
         if (strcmp(name, d->name) == 0) {
             return d;
diff --git a/block.c b/block.c
index 3bd594eb2aed..ddd743c44735 100644
--- a/block.c
+++ b/block.c
@@ -464,7 +464,7 @@ BlockDriver *bdrv_find_format(const char *format_name)
     /* The driver isn't registered, maybe we need to load a module */
     for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) {
         if (!strcmp(block_driver_modules[i].format_name, format_name)) {
-            block_module_load_one(block_driver_modules[i].library_name);
+            block_module_load(block_driver_modules[i].library_name);
             break;
         }
     }
@@ -981,7 +981,7 @@ BlockDriver *bdrv_find_protocol(const char *filename,
     for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) {
         if (block_driver_modules[i].protocol_name &&
             !strcmp(block_driver_modules[i].protocol_name, protocol)) {
-            block_module_load_one(block_driver_modules[i].library_name);
+            block_module_load(block_driver_modules[i].library_name);
             break;
         }
     }
diff --git a/block/dmg.c b/block/dmg.c
index 422136276aa4..b5a93b086b20 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -445,8 +445,8 @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
         return ret;
     }
 
-    block_module_load_one("dmg-bz2");
-    block_module_load_one("dmg-lzfse");
+    block_module_load("dmg-bz2");
+    block_module_load("dmg-lzfse");
 
     s->n_chunks = 0;
     s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
diff --git a/hw/core/qdev.c b/hw/core/qdev.c
index 0806d8fcaaac..25dfc0846801 100644
--- a/hw/core/qdev.c
+++ b/hw/core/qdev.c
@@ -148,7 +148,7 @@ bool qdev_set_parent_bus(DeviceState *dev, BusState *bus, Error **errp)
 DeviceState *qdev_new(const char *name)
 {
     if (!object_class_by_name(name)) {
-        module_load_qom_one(name);
+        module_load_qom(name);
     }
     return DEVICE(object_new(name));
 }
diff --git a/include/qemu/module.h b/include/qemu/module.h
index 8c012bbe038d..b7911ce79161 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -61,16 +61,16 @@ typedef enum {
 #define fuzz_target_init(function) module_init(function, \
                                                MODULE_INIT_FUZZ_TARGET)
 #define migration_init(function) module_init(function, MODULE_INIT_MIGRATION)
-#define block_module_load_one(lib) module_load_one("block-", lib)
-#define ui_module_load_one(lib) module_load_one("ui-", lib)
-#define audio_module_load_one(lib) module_load_one("audio-", lib)
+#define block_module_load(lib) module_load("block-", lib)
+#define ui_module_load(lib) module_load("ui-", lib)
+#define audio_module_load(lib) module_load("audio-", lib)
 
 void register_module_init(void (*fn)(void), module_init_type type);
 void register_dso_module_init(void (*fn)(void), module_init_type type);
 
 void module_call_init(module_init_type type);
-bool module_load_one(const char *prefix, const char *lib_name);
-void module_load_qom_one(const char *type);
+bool module_load(const char *prefix, const char *lib_name);
+void module_load_qom(const char *type);
 void module_load_qom_all(void);
 void module_allow_arch(const char *arch);
 
diff --git a/qom/object.c b/qom/object.c
index e5cef30f6d1a..aba942bdf31c 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -526,7 +526,7 @@ void object_initialize(void *data, size_t size, const char *typename)
 
 #ifdef CONFIG_MODULES
     if (!type) {
-        module_load_qom_one(typename);
+        module_load_qom(typename);
         type = type_get_by_name(typename);
     }
 #endif
@@ -1033,7 +1033,7 @@ ObjectClass *module_object_class_by_name(const char *typename)
     oc = object_class_by_name(typename);
 #ifdef CONFIG_MODULES
     if (!oc) {
-        module_load_qom_one(typename);
+        module_load_qom(typename);
         oc = object_class_by_name(typename);
     }
 #endif
diff --git a/softmmu/qtest.c b/softmmu/qtest.c
index ff74c5d7092e..774354565165 100644
--- a/softmmu/qtest.c
+++ b/softmmu/qtest.c
@@ -756,7 +756,7 @@ static void qtest_process_command(CharBackend *chr, gchar **words)
         g_assert(words[1] && words[2]);
 
         qtest_send_prefix(chr);
-        if (module_load_one(words[1], words[2])) {
+        if (module_load(words[1], words[2])) {
             qtest_sendf(chr, "OK\n");
         } else {
             qtest_sendf(chr, "FAIL\n");
diff --git a/ui/console.c b/ui/console.c
index 65c117874ca0..44dfb0f52b1c 100644
--- a/ui/console.c
+++ b/ui/console.c
@@ -2632,7 +2632,7 @@ bool qemu_display_find_default(DisplayOptions *opts)
 
     for (i = 0; i < (int)ARRAY_SIZE(prio); i++) {
         if (dpys[prio[i]] == NULL) {
-            ui_module_load_one(DisplayType_str(prio[i]));
+            ui_module_load(DisplayType_str(prio[i]));
         }
         if (dpys[prio[i]] == NULL) {
             continue;
@@ -2650,7 +2650,7 @@ void qemu_display_early_init(DisplayOptions *opts)
         return;
     }
     if (dpys[opts->type] == NULL) {
-        ui_module_load_one(DisplayType_str(opts->type));
+        ui_module_load(DisplayType_str(opts->type));
     }
     if (dpys[opts->type] == NULL) {
         error_report("Display '%s' is not available.",
@@ -2680,7 +2680,7 @@ void qemu_display_help(void)
     printf("none\n");
     for (idx = DISPLAY_TYPE_NONE; idx < DISPLAY_TYPE__MAX; idx++) {
         if (!dpys[idx]) {
-            ui_module_load_one(DisplayType_str(idx));
+            ui_module_load(DisplayType_str(idx));
         }
         if (dpys[idx]) {
             printf("%s\n",  DisplayType_str(dpys[idx]->type));
diff --git a/util/module.c b/util/module.c
index 8563edd6267c..ad89cd50dc2a 100644
--- a/util/module.c
+++ b/util/module.c
@@ -206,7 +206,7 @@ out:
 }
 #endif
 
-bool module_load_one(const char *prefix, const char *lib_name)
+bool module_load(const char *prefix, const char *lib_name)
 {
     bool success = false;
 
@@ -254,7 +254,7 @@ bool module_load_one(const char *prefix, const char *lib_name)
             if (strcmp(modinfo->name, module_name) == 0) {
                 /* we depend on other module(s) */
                 for (sl = modinfo->deps; *sl != NULL; sl++) {
-                    module_load_one("", *sl);
+                    module_load("", *sl);
                 }
             } else {
                 for (sl = modinfo->deps; *sl != NULL; sl++) {
@@ -312,7 +312,7 @@ bool module_load_one(const char *prefix, const char *lib_name)
 
 static bool module_loaded_qom_all;
 
-void module_load_qom_one(const char *type)
+void module_load_qom(const char *type)
 {
     const QemuModinfo *modinfo;
     const char **sl;
@@ -331,7 +331,7 @@ void module_load_qom_one(const char *type)
         }
         for (sl = modinfo->objs; *sl != NULL; sl++) {
             if (strcmp(type, *sl) == 0) {
-                module_load_one("", modinfo->name);
+                module_load("", modinfo->name);
             }
         }
     }
@@ -352,7 +352,7 @@ void module_load_qom_all(void)
         if (!module_check_arch(modinfo)) {
             continue;
         }
-        module_load_one("", modinfo->name);
+        module_load("", modinfo->name);
     }
     module_loaded_qom_all = true;
 }
@@ -368,7 +368,7 @@ void qemu_load_module_for_opts(const char *group)
         }
         for (sl = modinfo->opts; *sl != NULL; sl++) {
             if (strcmp(group, *sl) == 0) {
-                module_load_one("", modinfo->name);
+                module_load("", modinfo->name);
             }
         }
     }
@@ -378,7 +378,7 @@ void qemu_load_module_for_opts(const char *group)
 
 void module_allow_arch(const char *arch) {}
 void qemu_load_module_for_opts(const char *group) {}
-void module_load_qom_one(const char *type) {}
+void module_load_qom(const char *type) {}
 void module_load_qom_all(void) {}
 
 #endif
-- 
2.38.1

[PULL 10/12] module: add Error arguments to module_load and module_load_qom

[Paolo Bonzini]

From: Claudio Fontana <cfontana@suse.de>

improve error handling during module load, by changing:

bool module_load(const char *prefix, const char *lib_name);
void module_load_qom(const char *type);

to:

int module_load(const char *prefix, const char *name, Error **errp);
int module_load_qom(const char *type, Error **errp);

where the return value is:

 -1 on module load error, and errp is set with the error
  0 on module or one of its dependencies are not installed
  1 on module load success
  2 on module load success (module already loaded or built-in)

module_load_qom_one has been introduced in:

commit 28457744c345 ("module: qom module support"), which built on top of
module_load_one, but discarded the bool return value. Restore it.

Adapt all callers to emit errors, or ignore them, or fail hard,
as appropriate in each context.

Replace the previous emission of errors via fprintf in _some_ error
conditions with Error and error_report, so as to emit to the appropriate
target.

A memory leak is also fixed as part of the module_load changes.

audio: when attempting to load an audio module, report module load errors.
Note that still for some callers, a single issue may generate multiple
error reports, and this could be improved further.
Regarding the audio code itself, audio_add() seems to ignore errors,
and this should probably be improved.

block: when attempting to load a block module, report module load errors.
For the code paths that already use the Error API, take advantage of those
to report module load errors into the Error parameter.
For the other code paths, we currently emit the error, but this could be
improved further by adding Error parameters to all possible code paths.

console: when attempting to load a display module, report module load errors.

qdev: when creating a new qdev Device object (DeviceState), report load errors.
      If a module cannot be loaded to create that device, now abort execution
      (if no CONFIG_MODULE) or exit (if CONFIG_MODULE).

qom/object.c: when initializing a QOM object, or looking up class_by_name,
              report module load errors.

qtest: when processing the "module_load" qtest command, report errors
       in the load of the module.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220929093035.4231-4-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 audio/audio.c         |  16 ++--
 block.c               |  20 +++-
 block/dmg.c           |  14 ++-
 hw/core/qdev.c        |  17 +++-
 include/qemu/module.h |  37 +++++++-
 qom/object.c          |  18 +++-
 softmmu/qtest.c       |   8 +-
 ui/console.c          |  18 +++-
 util/module.c         | 209 +++++++++++++++++++++++-------------------
 9 files changed, 234 insertions(+), 123 deletions(-)

diff --git a/audio/audio.c b/audio/audio.c
index 379f19dc891f..065602ce1b95 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -73,20 +73,24 @@ void audio_driver_register(audio_driver *drv)
 audio_driver *audio_driver_lookup(const char *name)
 {
     struct audio_driver *d;
+    Error *local_err = NULL;
+    int rv;
 
     QLIST_FOREACH(d, &audio_drivers, next) {
         if (strcmp(name, d->name) == 0) {
             return d;
         }
     }
-
-    audio_module_load(name);
-    QLIST_FOREACH(d, &audio_drivers, next) {
-        if (strcmp(name, d->name) == 0) {
-            return d;
+    rv = audio_module_load(name, &local_err);
+    if (rv > 0) {
+        QLIST_FOREACH(d, &audio_drivers, next) {
+            if (strcmp(name, d->name) == 0) {
+                return d;
+            }
         }
+    } else if (rv < 0) {
+        error_report_err(local_err);
     }
-
     return NULL;
 }
 
diff --git a/block.c b/block.c
index ddd743c44735..c5e20c0beae3 100644
--- a/block.c
+++ b/block.c
@@ -464,12 +464,18 @@ BlockDriver *bdrv_find_format(const char *format_name)
     /* The driver isn't registered, maybe we need to load a module */
     for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) {
         if (!strcmp(block_driver_modules[i].format_name, format_name)) {
-            block_module_load(block_driver_modules[i].library_name);
+            Error *local_err = NULL;
+            int rv = block_module_load(block_driver_modules[i].library_name,
+                                       &local_err);
+            if (rv > 0) {
+                return bdrv_do_find_format(format_name);
+            } else if (rv < 0) {
+                error_report_err(local_err);
+            }
             break;
         }
     }
-
-    return bdrv_do_find_format(format_name);
+    return NULL;
 }
 
 static int bdrv_format_is_whitelisted(const char *format_name, bool read_only)
@@ -981,12 +987,16 @@ BlockDriver *bdrv_find_protocol(const char *filename,
     for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) {
         if (block_driver_modules[i].protocol_name &&
             !strcmp(block_driver_modules[i].protocol_name, protocol)) {
-            block_module_load(block_driver_modules[i].library_name);
+            int rv = block_module_load(block_driver_modules[i].library_name, errp);
+            if (rv > 0) {
+                drv1 = bdrv_do_find_protocol(protocol);
+            } else if (rv < 0) {
+                return NULL;
+            }
             break;
         }
     }
 
-    drv1 = bdrv_do_find_protocol(protocol);
     if (!drv1) {
         error_setg(errp, "Unknown protocol '%s'", protocol);
     }
diff --git a/block/dmg.c b/block/dmg.c
index b5a93b086b20..ba8ec344d479 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -444,9 +444,17 @@ static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
     if (ret < 0) {
         return ret;
     }
-
-    block_module_load("dmg-bz2");
-    block_module_load("dmg-lzfse");
+    /*
+     * NB: if uncompress submodules are absent,
+     * ie block_module_load return value == 0, the function pointers
+     * dmg_uncompress_bz2 and dmg_uncompress_lzfse will be NULL.
+     */
+    if (block_module_load("dmg-bz2", errp) < 0) {
+        return -EINVAL;
+    }
+    if (block_module_load("dmg-lzfse", errp) < 0) {
+        return -EINVAL;
+    }
 
     s->n_chunks = 0;
     s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
diff --git a/hw/core/qdev.c b/hw/core/qdev.c
index 25dfc0846801..014550190447 100644
--- a/hw/core/qdev.c
+++ b/hw/core/qdev.c
@@ -147,8 +147,21 @@ bool qdev_set_parent_bus(DeviceState *dev, BusState *bus, Error **errp)
 
 DeviceState *qdev_new(const char *name)
 {
-    if (!object_class_by_name(name)) {
-        module_load_qom(name);
+    ObjectClass *oc = object_class_by_name(name);
+#ifdef CONFIG_MODULES
+    if (!oc) {
+        int rv = module_load_qom(name, &error_fatal);
+        if (rv > 0) {
+            oc = object_class_by_name(name);
+        } else {
+            error_report("could not find a module for type '%s'", name);
+            exit(1);
+        }
+    }
+#endif
+    if (!oc) {
+        error_report("unknown type '%s'", name);
+        abort();
     }
     return DEVICE(object_new(name));
 }
diff --git a/include/qemu/module.h b/include/qemu/module.h
index b7911ce79161..c37ce74b16ff 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -61,16 +61,43 @@ typedef enum {
 #define fuzz_target_init(function) module_init(function, \
                                                MODULE_INIT_FUZZ_TARGET)
 #define migration_init(function) module_init(function, MODULE_INIT_MIGRATION)
-#define block_module_load(lib) module_load("block-", lib)
-#define ui_module_load(lib) module_load("ui-", lib)
-#define audio_module_load(lib) module_load("audio-", lib)
+#define block_module_load(lib, errp) module_load("block-", lib, errp)
+#define ui_module_load(lib, errp) module_load("ui-", lib, errp)
+#define audio_module_load(lib, errp) module_load("audio-", lib, errp)
 
 void register_module_init(void (*fn)(void), module_init_type type);
 void register_dso_module_init(void (*fn)(void), module_init_type type);
 
 void module_call_init(module_init_type type);
-bool module_load(const char *prefix, const char *lib_name);
-void module_load_qom(const char *type);
+
+/*
+ * module_load: attempt to load a module from a set of directories
+ *
+ * directories searched are:
+ * - getenv("QEMU_MODULE_DIR")
+ * - get_relocated_path(CONFIG_QEMU_MODDIR);
+ * - /var/run/qemu/${version_dir}
+ *
+ * prefix:         a subsystem prefix, or the empty string ("audio-", ..., "")
+ * name:           name of the module
+ * errp:           error to set in case the module is found, but load failed.
+ *
+ * Return value:   -1 on error (errp set if not NULL).
+ *                 0 if module or one of its dependencies are not installed,
+ *                 1 if the module is found and loaded,
+ *                 2 if the module is already loaded, or module is built-in.
+ */
+int module_load(const char *prefix, const char *name, Error **errp);
+
+/*
+ * module_load_qom: attempt to load a module to provide a QOM type
+ *
+ * type:           the type to be provided
+ * errp:           error to set.
+ *
+ * Return value:   as per module_load.
+ */
+int module_load_qom(const char *type, Error **errp);
 void module_load_qom_all(void);
 void module_allow_arch(const char *arch);
 
diff --git a/qom/object.c b/qom/object.c
index aba942bdf31c..e25f1e96db1e 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -526,8 +526,13 @@ void object_initialize(void *data, size_t size, const char *typename)
 
 #ifdef CONFIG_MODULES
     if (!type) {
-        module_load_qom(typename);
-        type = type_get_by_name(typename);
+        int rv = module_load_qom(typename, &error_fatal);
+        if (rv > 0) {
+            type = type_get_by_name(typename);
+        } else {
+            error_report("missing object type '%s'", typename);
+            exit(1);
+        }
     }
 #endif
     if (!type) {
@@ -1033,8 +1038,13 @@ ObjectClass *module_object_class_by_name(const char *typename)
     oc = object_class_by_name(typename);
 #ifdef CONFIG_MODULES
     if (!oc) {
-        module_load_qom(typename);
-        oc = object_class_by_name(typename);
+        Error *local_err = NULL;
+        int rv = module_load_qom(typename, &local_err);
+        if (rv > 0) {
+            oc = object_class_by_name(typename);
+        } else if (rv < 0) {
+            error_report_err(local_err);
+        }
     }
 #endif
     return oc;
diff --git a/softmmu/qtest.c b/softmmu/qtest.c
index 774354565165..d3e0ab4eda26 100644
--- a/softmmu/qtest.c
+++ b/softmmu/qtest.c
@@ -753,12 +753,18 @@ static void qtest_process_command(CharBackend *chr, gchar **words)
         qtest_sendf(chr, "OK %"PRIi64"\n",
                     (int64_t)qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL));
     } else if (strcmp(words[0], "module_load") == 0) {
+        Error *local_err = NULL;
+        int rv;
         g_assert(words[1] && words[2]);
 
         qtest_send_prefix(chr);
-        if (module_load(words[1], words[2])) {
+        rv = module_load(words[1], words[2], &local_err);
+        if (rv > 0) {
             qtest_sendf(chr, "OK\n");
         } else {
+            if (rv < 0) {
+                error_report_err(local_err);
+            }
             qtest_sendf(chr, "FAIL\n");
         }
     } else if (qtest_enabled() && strcmp(words[0], "clock_set") == 0) {
diff --git a/ui/console.c b/ui/console.c
index 44dfb0f52b1c..3c0d9b061ac5 100644
--- a/ui/console.c
+++ b/ui/console.c
@@ -2632,7 +2632,11 @@ bool qemu_display_find_default(DisplayOptions *opts)
 
     for (i = 0; i < (int)ARRAY_SIZE(prio); i++) {
         if (dpys[prio[i]] == NULL) {
-            ui_module_load(DisplayType_str(prio[i]));
+            Error *local_err = NULL;
+            int rv = ui_module_load(DisplayType_str(prio[i]), &local_err);
+            if (rv < 0) {
+                error_report_err(local_err);
+            }
         }
         if (dpys[prio[i]] == NULL) {
             continue;
@@ -2650,7 +2654,11 @@ void qemu_display_early_init(DisplayOptions *opts)
         return;
     }
     if (dpys[opts->type] == NULL) {
-        ui_module_load(DisplayType_str(opts->type));
+        Error *local_err = NULL;
+        int rv = ui_module_load(DisplayType_str(opts->type), &local_err);
+        if (rv < 0) {
+            error_report_err(local_err);
+        }
     }
     if (dpys[opts->type] == NULL) {
         error_report("Display '%s' is not available.",
@@ -2680,7 +2688,11 @@ void qemu_display_help(void)
     printf("none\n");
     for (idx = DISPLAY_TYPE_NONE; idx < DISPLAY_TYPE__MAX; idx++) {
         if (!dpys[idx]) {
-            ui_module_load(DisplayType_str(idx));
+            Error *local_err = NULL;
+            int rv = ui_module_load(DisplayType_str(idx), &local_err);
+            if (rv < 0) {
+                error_report_err(local_err);
+            }
         }
         if (dpys[idx]) {
             printf("%s\n",  DisplayType_str(dpys[idx]->type));
diff --git a/util/module.c b/util/module.c
index ad89cd50dc2a..32e263163c75 100644
--- a/util/module.c
+++ b/util/module.c
@@ -21,6 +21,7 @@
 #include "qemu/module.h"
 #include "qemu/cutils.h"
 #include "qemu/config-file.h"
+#include "qapi/error.h"
 #ifdef CONFIG_MODULE_UPGRADES
 #include "qemu-version.h"
 #endif
@@ -144,25 +145,22 @@ static bool module_check_arch(const QemuModinfo *modinfo)
     return true;
 }
 
-static int module_load_file(const char *fname, bool export_symbols)
+/*
+ * module_load_dso: attempt to load an existing dso file
+ *
+ * fname:          full pathname of the file to load
+ * export_symbols: if true, add the symbols to the global name space
+ * errp:           error to set.
+ *
+ * Return value:   true on success, false on error, and errp will be set.
+ */
+static bool module_load_dso(const char *fname, bool export_symbols,
+                            Error **errp)
 {
     GModule *g_module;
     void (*sym)(void);
-    const char *dsosuf = CONFIG_HOST_DSOSUF;
-    int len = strlen(fname);
-    int suf_len = strlen(dsosuf);
     ModuleEntry *e, *next;
-    int ret, flags;
-
-    if (len <= suf_len || strcmp(&fname[len - suf_len], dsosuf)) {
-        /* wrong suffix */
-        ret = -EINVAL;
-        goto out;
-    }
-    if (access(fname, F_OK)) {
-        ret = -ENOENT;
-        goto out;
-    }
+    int flags;
 
     assert(QTAILQ_EMPTY(&dso_init_list));
 
@@ -172,46 +170,38 @@ static int module_load_file(const char *fname, bool export_symbols)
     }
     g_module = g_module_open(fname, flags);
     if (!g_module) {
-        fprintf(stderr, "Failed to open module: %s\n",
-                g_module_error());
-        ret = -EINVAL;
-        goto out;
+        error_setg(errp, "failed to open module: %s", g_module_error());
+        return false;
     }
     if (!g_module_symbol(g_module, DSO_STAMP_FUN_STR, (gpointer *)&sym)) {
-        fprintf(stderr, "Failed to initialize module: %s\n",
-                fname);
-        /* Print some info if this is a QEMU module (but from different build),
-         * this will make debugging user problems easier. */
+        error_setg(errp, "failed to initialize module: %s", fname);
+        /*
+         * Print some info if this is a QEMU module (but from different build),
+         * this will make debugging user problems easier.
+         */
         if (g_module_symbol(g_module, "qemu_module_dummy", (gpointer *)&sym)) {
-            fprintf(stderr,
-                    "Note: only modules from the same build can be loaded.\n");
+            error_append_hint(errp,
+                "Only modules from the same build can be loaded.\n");
         }
         g_module_close(g_module);
-        ret = -EINVAL;
-    } else {
-        QTAILQ_FOREACH(e, &dso_init_list, node) {
-            e->init();
-            register_module_init(e->init, e->type);
-        }
-        ret = 0;
+        return false;
     }
 
+    QTAILQ_FOREACH(e, &dso_init_list, node) {
+        e->init();
+        register_module_init(e->init, e->type);
+    }
     trace_module_load_module(fname);
     QTAILQ_FOREACH_SAFE(e, &dso_init_list, node, next) {
         QTAILQ_REMOVE(&dso_init_list, e, node);
         g_free(e);
     }
-out:
-    return ret;
+    return true;
 }
-#endif
 
-bool module_load(const char *prefix, const char *lib_name)
+int module_load(const char *prefix, const char *name, Error **errp)
 {
-    bool success = false;
-
-#ifdef CONFIG_MODULES
-    char *fname = NULL;
+    int rv = -1;
 #ifdef CONFIG_MODULE_UPGRADES
     char *version_dir;
 #endif
@@ -219,54 +209,29 @@ bool module_load(const char *prefix, const char *lib_name)
     char *dirs[5];
     char *module_name;
     int i = 0, n_dirs = 0;
-    int ret;
     bool export_symbols = false;
     static GHashTable *loaded_modules;
     const QemuModinfo *modinfo;
     const char **sl;
 
     if (!g_module_supported()) {
-        fprintf(stderr, "Module is not supported by system.\n");
-        return false;
+        error_setg(errp, "%s", "this platform does not support GLib modules");
+        return -1;
     }
 
     if (!loaded_modules) {
         loaded_modules = g_hash_table_new(g_str_hash, g_str_equal);
     }
 
-    module_name = g_strdup_printf("%s%s", prefix, lib_name);
+    /* allocate all resources managed by the out: label here */
+    module_name = g_strdup_printf("%s%s", prefix, name);
 
     if (g_hash_table_contains(loaded_modules, module_name)) {
         g_free(module_name);
-        return true;
+        return 2; /* module already loaded */
     }
     g_hash_table_add(loaded_modules, module_name);
 
-    for (modinfo = module_info; modinfo->name != NULL; modinfo++) {
-        if (modinfo->arch) {
-            if (strcmp(modinfo->name, module_name) == 0) {
-                if (!module_check_arch(modinfo)) {
-                    return false;
-                }
-            }
-        }
-        if (modinfo->deps) {
-            if (strcmp(modinfo->name, module_name) == 0) {
-                /* we depend on other module(s) */
-                for (sl = modinfo->deps; *sl != NULL; sl++) {
-                    module_load("", *sl);
-                }
-            } else {
-                for (sl = modinfo->deps; *sl != NULL; sl++) {
-                    if (strcmp(module_name, *sl) == 0) {
-                        /* another module depends on us */
-                        export_symbols = true;
-                    }
-                }
-            }
-        }
-    }
-
     search_dir = getenv("QEMU_MODULE_DIR");
     if (search_dir != NULL) {
         dirs[n_dirs++] = g_strdup_printf("%s", search_dir);
@@ -279,46 +244,87 @@ bool module_load(const char *prefix, const char *lib_name)
                              '_');
     dirs[n_dirs++] = g_strdup_printf("/var/run/qemu/%s", version_dir);
 #endif
-
     assert(n_dirs <= ARRAY_SIZE(dirs));
 
-    for (i = 0; i < n_dirs; i++) {
-        fname = g_strdup_printf("%s/%s%s",
-                dirs[i], module_name, CONFIG_HOST_DSOSUF);
-        ret = module_load_file(fname, export_symbols);
-        g_free(fname);
-        fname = NULL;
-        /* Try loading until loaded a module file */
-        if (!ret) {
-            success = true;
-            break;
+    /* end of resources managed by the out: label */
+
+    for (modinfo = module_info; modinfo->name != NULL; modinfo++) {
+        if (modinfo->arch) {
+            if (strcmp(modinfo->name, module_name) == 0) {
+                if (!module_check_arch(modinfo)) {
+                    error_setg(errp, "module arch does not match: "
+                        "expected '%s', got '%s'", module_arch, modinfo->arch);
+                    goto out;
+                }
+            }
+        }
+        if (modinfo->deps) {
+            if (strcmp(modinfo->name, module_name) == 0) {
+                /* we depend on other module(s) */
+                for (sl = modinfo->deps; *sl != NULL; sl++) {
+                    int subrv = module_load("", *sl, errp);
+                    if (subrv <= 0) {
+                        rv = subrv;
+                        goto out;
+                    }
+                }
+            } else {
+                for (sl = modinfo->deps; *sl != NULL; sl++) {
+                    if (strcmp(module_name, *sl) == 0) {
+                        /* another module depends on us */
+                        export_symbols = true;
+                    }
+                }
+            }
         }
     }
 
-    if (!success) {
+    for (i = 0; i < n_dirs; i++) {
+        char *fname = g_strdup_printf("%s/%s%s",
+                                      dirs[i], module_name, CONFIG_HOST_DSOSUF);
+        int ret = access(fname, F_OK);
+        if (ret != 0 && (errno == ENOENT || errno == ENOTDIR)) {
+            /*
+             * if we don't find the module in this dir, try the next one.
+             * If we don't find it in any dir, that can be fine too: user
+             * did not install the module. We will return 0 in this case
+             * with no error set.
+             */
+            g_free(fname);
+            continue;
+        } else if (ret != 0) {
+            /* most common is EACCES here */
+            error_setg_errno(errp, errno, "error trying to access %s", fname);
+        } else if (module_load_dso(fname, export_symbols, errp)) {
+            rv = 1; /* module successfully loaded */
+        }
+        g_free(fname);
+        goto out;
+    }
+    rv = 0; /* module not found */
+
+out:
+    if (rv <= 0) {
         g_hash_table_remove(loaded_modules, module_name);
         g_free(module_name);
     }
-
     for (i = 0; i < n_dirs; i++) {
         g_free(dirs[i]);
     }
-
-#endif
-    return success;
+    return rv;
 }
 
-#ifdef CONFIG_MODULES
-
 static bool module_loaded_qom_all;
 
-void module_load_qom(const char *type)
+int module_load_qom(const char *type, Error **errp)
 {
     const QemuModinfo *modinfo;
     const char **sl;
+    int rv = 0;
 
     if (!type) {
-        return;
+        error_setg(errp, "%s", "type is NULL");
+        return -1;
     }
 
     trace_module_lookup_object_type(type);
@@ -331,15 +337,24 @@ void module_load_qom(const char *type)
         }
         for (sl = modinfo->objs; *sl != NULL; sl++) {
             if (strcmp(type, *sl) == 0) {
-                module_load("", modinfo->name);
+                if (rv > 0) {
+                    error_setg(errp, "multiple modules providing '%s'", type);
+                    return -1;
+                }
+                rv = module_load("", modinfo->name, errp);
+                if (rv < 0) {
+                    return rv;
+                }
             }
         }
     }
+    return rv;
 }
 
 void module_load_qom_all(void)
 {
     const QemuModinfo *modinfo;
+    Error *local_err = NULL;
 
     if (module_loaded_qom_all) {
         return;
@@ -352,7 +367,9 @@ void module_load_qom_all(void)
         if (!module_check_arch(modinfo)) {
             continue;
         }
-        module_load("", modinfo->name);
+        if (module_load("", modinfo->name, &local_err) < 0) {
+            error_report_err(local_err);
+        }
     }
     module_loaded_qom_all = true;
 }
@@ -368,7 +385,10 @@ void qemu_load_module_for_opts(const char *group)
         }
         for (sl = modinfo->opts; *sl != NULL; sl++) {
             if (strcmp(group, *sl) == 0) {
-                module_load("", modinfo->name);
+                Error *local_err = NULL;
+                if (module_load("", modinfo->name, &local_err) < 0) {
+                    error_report_err(local_err);
+                }
             }
         }
     }
@@ -378,7 +398,8 @@ void qemu_load_module_for_opts(const char *group)
 
 void module_allow_arch(const char *arch) {}
 void qemu_load_module_for_opts(const char *group) {}
-void module_load_qom(const char *type) {}
+int module_load(const char *prefix, const char *name, Error **errp) { return 2; }
+int module_load_qom(const char *type, Error **errp) { return 2; }
 void module_load_qom_all(void) {}
 
 #endif
-- 
2.38.1

[PULL 11/12] dmg: warn when opening dmg images containing blocks of unknown type

[Paolo Bonzini]

From: Kevin Wolf <kwolf@redhat.com>

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220929093035.4231-5-cfontana@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 block/dmg.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/block/dmg.c b/block/dmg.c
index ba8ec344d479..675e840ca587 100644
--- a/block/dmg.c
+++ b/block/dmg.c
@@ -254,6 +254,25 @@ static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds,
     for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
         s->types[i] = buff_read_uint32(buffer, offset);
         if (!dmg_is_known_block_type(s->types[i])) {
+            switch (s->types[i]) {
+            case UDBZ:
+                warn_report_once("dmg-bzip2 module is missing, accessing bzip2 "
+                                 "compressed blocks will result in I/O errors");
+                break;
+            case ULFO:
+                warn_report_once("dmg-lzfse module is missing, accessing lzfse "
+                                 "compressed blocks will result in I/O errors");
+                break;
+            case UDCM:
+            case UDLE:
+                /* Comments and last entry can be ignored without problems */
+                break;
+            default:
+                warn_report_once("Image contains chunks of unknown type %x, "
+                                 "accessing them will result in I/O errors",
+                                 s->types[i]);
+                break;
+            }
             chunk_count--;
             i--;
             offset += 40;
-- 
2.38.1

[PULL 12/12] accel: abort if we fail to load the accelerator plugin

[Paolo Bonzini]

From: Claudio Fontana <cfontana@suse.de>

if QEMU is configured with modules enabled, it is possible that the
load of an accelerator module will fail.
Exit in this case, relying on module_object_class_by_name to report
the specific load error if any.

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

[claudio: changed abort() to exit(1)]
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20220929093035.4231-6-cfontana@suse.de>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 accel/accel-softmmu.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/accel/accel-softmmu.c b/accel/accel-softmmu.c
index 67276e4f5222..f9cdafb148ac 100644
--- a/accel/accel-softmmu.c
+++ b/accel/accel-softmmu.c
@@ -66,6 +66,7 @@ void accel_init_ops_interfaces(AccelClass *ac)
 {
     const char *ac_name;
     char *ops_name;
+    ObjectClass *oc;
     AccelOpsClass *ops;
 
     ac_name = object_class_get_name(OBJECT_CLASS(ac));
@@ -73,8 +74,13 @@ void accel_init_ops_interfaces(AccelClass *ac)
 
     ops_name = g_strdup_printf("%s" ACCEL_OPS_SUFFIX, ac_name);
     ops = ACCEL_OPS_CLASS(module_object_class_by_name(ops_name));
+    oc = module_object_class_by_name(ops_name);
+    if (!oc) {
+        error_report("fatal: could not load module for type '%s'", ops_name);
+        exit(1);
+    }
     g_free(ops_name);
-
+    ops = ACCEL_OPS_CLASS(oc);
     /*
      * all accelerators need to define ops, providing at least a mandatory
      * non-NULL create_vcpu_thread operation.
-- 
2.38.1

Re: [PULL 12/12] accel: abort if we fail to load the accelerator plugin

[Claudio Fontana]

Hi all,

and thanks Paolo for taking care of this series, I think I noticed something that seems off:

On 11/6/22 09:51, Paolo Bonzini wrote:
> From: Claudio Fontana <cfontana@suse.de>
> 
> if QEMU is configured with modules enabled, it is possible that the
> load of an accelerator module will fail.
> Exit in this case, relying on module_object_class_by_name to report
> the specific load error if any.
> 
> Signed-off-by: Claudio Fontana <cfontana@suse.de>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> 
> [claudio: changed abort() to exit(1)]
> Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Reviewed-by: Markus Armbruster <armbru@redhat.com>
> Message-Id: <20220929093035.4231-6-cfontana@suse.de>
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  accel/accel-softmmu.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/accel/accel-softmmu.c b/accel/accel-softmmu.c
> index 67276e4f5222..f9cdafb148ac 100644
> --- a/accel/accel-softmmu.c
> +++ b/accel/accel-softmmu.c
> @@ -66,6 +66,7 @@ void accel_init_ops_interfaces(AccelClass *ac)
>  {
>      const char *ac_name;
>      char *ops_name;
> +    ObjectClass *oc;
>      AccelOpsClass *ops;
>  
>      ac_name = object_class_get_name(OBJECT_CLASS(ac));
> @@ -73,8 +74,13 @@ void accel_init_ops_interfaces(AccelClass *ac)
>  
>      ops_name = g_strdup_printf("%s" ACCEL_OPS_SUFFIX, ac_name);
>      ops = ACCEL_OPS_CLASS(module_object_class_by_name(ops_name));

I think this last line should be removed. I somehow left it there by mistake.
Not sure if it hurts, but we assign to "ops" here,

only to reassign to the same variable...

I 

> +    oc = module_object_class_by_name(ops_name);
> +    if (!oc) {
> +        error_report("fatal: could not load module for type '%s'", ops_name);
> +        exit(1);
> +    }
>      g_free(ops_name);
> -
> +    ops = ACCEL_OPS_CLASS(oc);

here. Do I see it right?

>      /*
>       * all accelerators need to define ops, providing at least a mandatory
>       * non-NULL create_vcpu_thread operation.

So I suggest:

-     ops = ACCEL_OPS_CLASS(module_object_class_by_name(ops_name));                                                                          

Thanks and sorry for the oversight,

Claudio

Re: [PULL 00/12] Misc bugfix patches (+ improved module errors) for QEMU 7.2

[Stefan Hajnoczi]

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Applied, thanks.

Please update the changelog at https://wiki.qemu.org/ChangeLog/7.2 for any user-visible changes.

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