block/backup-top.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
bdrv_open_driver() allocates bs->opaque according to drv->instance_size.
There is no need to allocate it and overwrite opaque in
bdrv_backup_top_append().
Reproducer:
$ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start
==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226
==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762)
==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7)
==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289)
==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359)
==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190)
==29792== by 0x1CC11A: backup_job_create (backup.c:439)
==29792== by 0x1CD542: replication_start (replication.c:544)
==29792== by 0x1401B9: replication_start_all (replication.c:52)
==29792== by 0x128B50: test_secondary_start (test-replication.c:427)
...
Fixes: 7df7868b9640 ("block: introduce backup-top filter driver")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
---
block/backup-top.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/backup-top.c b/block/backup-top.c
index 7cdb1f8eba..617217374d 100644
--- a/block/backup-top.c
+++ b/block/backup-top.c
@@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source,
}
top->total_sectors = source->total_sectors;
- top->opaque = state = g_new0(BDRVBackupTopState, 1);
+ state = top->opaque;
bdrv_ref(target);
state->target = bdrv_attach_child(top, target, "target", &child_file, errp);
--
2.21.0
23.12.2019 12:06, Eiichi Tsukata wrote: > bdrv_open_driver() allocates bs->opaque according to drv->instance_size. > There is no need to allocate it and overwrite opaque in > bdrv_backup_top_append(). > > Reproducer: > > $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start > ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226 > ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762) > ==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7) > ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289) > ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359) > ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190) > ==29792== by 0x1CC11A: backup_job_create (backup.c:439) > ==29792== by 0x1CD542: replication_start (replication.c:544) > ==29792== by 0x1401B9: replication_start_all (replication.c:52) > ==29792== by 0x128B50: test_secondary_start (test-replication.c:427) > ... > > Fixes: 7df7868b9640 ("block: introduce backup-top filter driver") > Signed-off-by: Eiichi Tsukata <devel@etsukata.com> > --- > block/backup-top.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/block/backup-top.c b/block/backup-top.c > index 7cdb1f8eba..617217374d 100644 > --- a/block/backup-top.c > +++ b/block/backup-top.c > @@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, > } > > top->total_sectors = source->total_sectors; > - top->opaque = state = g_new0(BDRVBackupTopState, 1); > + state = top->opaque; > > bdrv_ref(target); > state->target = bdrv_attach_child(top, target, "target", &child_file, errp); > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> Hmm, it was not my idea, I just copied it from mirror.. And there should be the same leak. and may be in other places: # git grep 'opaque =.*g_new' block/backup-top.c: top->opaque = state = g_new0(BDRVBackupTopState, 1); block/file-posix.c: state->opaque = g_new0(BDRVRawReopenState, 1); block/gluster.c: state->opaque = g_new0(BDRVGlusterReopenState, 1); block/iscsi.c: bs->opaque = g_new0(struct IscsiLun, 1); block/mirror.c: bs_opaque = g_new0(MirrorBDSOpaque, 1); block/raw-format.c: reopen_state->opaque = g_new0(BDRVRawState, 1); block/sheepdog.c: re_s = state->opaque = g_new0(BDRVSheepdogReopenState, 1); -- Best regards, Vladimir
On 2019/12/23 21:40, Vladimir Sementsov-Ogievskiy wrote: > 23.12.2019 12:06, Eiichi Tsukata wrote: >> bdrv_open_driver() allocates bs->opaque according to drv->instance_size. >> There is no need to allocate it and overwrite opaque in >> bdrv_backup_top_append(). >> >> Reproducer: >> >> $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start >> ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226 >> ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762) >> ==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7) >> ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289) >> ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359) >> ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190) >> ==29792== by 0x1CC11A: backup_job_create (backup.c:439) >> ==29792== by 0x1CD542: replication_start (replication.c:544) >> ==29792== by 0x1401B9: replication_start_all (replication.c:52) >> ==29792== by 0x128B50: test_secondary_start (test-replication.c:427) >> ... >> >> Fixes: 7df7868b9640 ("block: introduce backup-top filter driver") >> Signed-off-by: Eiichi Tsukata <devel@etsukata.com> >> --- >> block/backup-top.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/block/backup-top.c b/block/backup-top.c >> index 7cdb1f8eba..617217374d 100644 >> --- a/block/backup-top.c >> +++ b/block/backup-top.c >> @@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, >> } >> >> top->total_sectors = source->total_sectors; >> - top->opaque = state = g_new0(BDRVBackupTopState, 1); >> + state = top->opaque; >> >> bdrv_ref(target); >> state->target = bdrv_attach_child(top, target, "target", &child_file, errp); >> > > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > > Hmm, it was not my idea, I just copied it from mirror.. And there should be the same leak. and > may be in other places: > > # git grep 'opaque =.*g_new' > block/backup-top.c: top->opaque = state = g_new0(BDRVBackupTopState, 1); > block/file-posix.c: state->opaque = g_new0(BDRVRawReopenState, 1); > block/gluster.c: state->opaque = g_new0(BDRVGlusterReopenState, 1); > block/iscsi.c: bs->opaque = g_new0(struct IscsiLun, 1); > block/mirror.c: bs_opaque = g_new0(MirrorBDSOpaque, 1); > block/raw-format.c: reopen_state->opaque = g_new0(BDRVRawState, 1); > block/sheepdog.c: re_s = state->opaque = g_new0(BDRVSheepdogReopenState, 1); > > > Thanks for reviewing. As you say, block/mirror.c has similar code. But it does not cause the leak. The difference is bdrv_mirror_top BlockDriver does not have .instance_size whereas bdrv_backup_top_filter BlockDriver has .instance_size = sizeof(BDRVBackupTopState). So when bdrv_open_driver() is called from mirror.c, g_malloc0(0) is called allocating nothing. Eiichi
Am 23.12.2019 um 14:40 hat Eiichi Tsukata geschrieben: > > > On 2019/12/23 21:40, Vladimir Sementsov-Ogievskiy wrote: > > 23.12.2019 12:06, Eiichi Tsukata wrote: > >> bdrv_open_driver() allocates bs->opaque according to drv->instance_size. > >> There is no need to allocate it and overwrite opaque in > >> bdrv_backup_top_append(). > >> > >> Reproducer: > >> > >> $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start > >> ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226 > >> ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762) > >> ==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7) > >> ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289) > >> ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359) > >> ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190) > >> ==29792== by 0x1CC11A: backup_job_create (backup.c:439) > >> ==29792== by 0x1CD542: replication_start (replication.c:544) > >> ==29792== by 0x1401B9: replication_start_all (replication.c:52) > >> ==29792== by 0x128B50: test_secondary_start (test-replication.c:427) > >> ... > >> > >> Fixes: 7df7868b9640 ("block: introduce backup-top filter driver") > >> Signed-off-by: Eiichi Tsukata <devel@etsukata.com> > >> --- > >> block/backup-top.c | 2 +- > >> 1 file changed, 1 insertion(+), 1 deletion(-) > >> > >> diff --git a/block/backup-top.c b/block/backup-top.c > >> index 7cdb1f8eba..617217374d 100644 > >> --- a/block/backup-top.c > >> +++ b/block/backup-top.c > >> @@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, > >> } > >> > >> top->total_sectors = source->total_sectors; > >> - top->opaque = state = g_new0(BDRVBackupTopState, 1); > >> + state = top->opaque; > >> > >> bdrv_ref(target); > >> state->target = bdrv_attach_child(top, target, "target", &child_file, errp); > >> > > > > Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> > > > > Hmm, it was not my idea, I just copied it from mirror.. And there should be the same leak. and > > may be in other places: > > > > # git grep 'opaque =.*g_new' > > block/backup-top.c: top->opaque = state = g_new0(BDRVBackupTopState, 1); Fixed by this patch. > > block/file-posix.c: state->opaque = g_new0(BDRVRawReopenState, 1); > > block/gluster.c: state->opaque = g_new0(BDRVGlusterReopenState, 1); > > block/raw-format.c: reopen_state->opaque = g_new0(BDRVRawState, 1); > > block/sheepdog.c: re_s = state->opaque = g_new0(BDRVSheepdogReopenState, 1); Doing this for reopen state is fine. > > block/iscsi.c: bs->opaque = g_new0(struct IscsiLun, 1); This one looks kind of questionable. It basically builds its BlockDriveState manually without using any of the block layer open functions. > > block/mirror.c: bs_opaque = g_new0(MirrorBDSOpaque, 1); Harmless as Eiichi explained below, but not nice either. > Thanks for reviewing. > As you say, block/mirror.c has similar code. But it does not cause the leak. > The difference is bdrv_mirror_top BlockDriver does not have .instance_size > whereas bdrv_backup_top_filter BlockDriver has .instance_size = sizeof(BDRVBackupTopState). > So when bdrv_open_driver() is called from mirror.c, g_malloc0(0) is > called allocating nothing. I think it should still be changed just because it would make the code cleaner. It's always better to use common infrastructure than reimplementing it locally. Kevin
ping On 2019/12/23 18:06, Eiichi Tsukata wrote: > bdrv_open_driver() allocates bs->opaque according to drv->instance_size. > There is no need to allocate it and overwrite opaque in > bdrv_backup_top_append(). > > Reproducer: > > $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start > ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226 > ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762) > ==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7) > ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289) > ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359) > ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190) > ==29792== by 0x1CC11A: backup_job_create (backup.c:439) > ==29792== by 0x1CD542: replication_start (replication.c:544) > ==29792== by 0x1401B9: replication_start_all (replication.c:52) > ==29792== by 0x128B50: test_secondary_start (test-replication.c:427) > ... > > Fixes: 7df7868b9640 ("block: introduce backup-top filter driver") > Signed-off-by: Eiichi Tsukata <devel@etsukata.com> > --- > block/backup-top.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/block/backup-top.c b/block/backup-top.c > index 7cdb1f8eba..617217374d 100644 > --- a/block/backup-top.c > +++ b/block/backup-top.c > @@ -196,7 +196,7 @@ BlockDriverState *bdrv_backup_top_append(BlockDriverState *source, > } > > top->total_sectors = source->total_sectors; > - top->opaque = state = g_new0(BDRVBackupTopState, 1); > + state = top->opaque; > > bdrv_ref(target); > state->target = bdrv_attach_child(top, target, "target", &child_file, errp); >
Am 23.12.2019 um 10:06 hat Eiichi Tsukata geschrieben: > bdrv_open_driver() allocates bs->opaque according to drv->instance_size. > There is no need to allocate it and overwrite opaque in > bdrv_backup_top_append(). > > Reproducer: > > $ QTEST_QEMU_BINARY=./x86_64-softmmu/qemu-system-x86_64 valgrind -q --leak-check=full tests/test-replication -p /replication/secondary/start > ==29792== 24 bytes in 1 blocks are definitely lost in loss record 52 of 226 > ==29792== at 0x483AB1A: calloc (vg_replace_malloc.c:762) > ==29792== by 0x4B07CE0: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.6000.7) > ==29792== by 0x12BAB9: bdrv_open_driver (block.c:1289) > ==29792== by 0x12BEA9: bdrv_new_open_driver (block.c:1359) > ==29792== by 0x1D15CB: bdrv_backup_top_append (backup-top.c:190) > ==29792== by 0x1CC11A: backup_job_create (backup.c:439) > ==29792== by 0x1CD542: replication_start (replication.c:544) > ==29792== by 0x1401B9: replication_start_all (replication.c:52) > ==29792== by 0x128B50: test_secondary_start (test-replication.c:427) > ... > > Fixes: 7df7868b9640 ("block: introduce backup-top filter driver") > Signed-off-by: Eiichi Tsukata <devel@etsukata.com> Thanks, applied to the block layer. Kevin
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