On Wed, May 07, 2025 at 10:07:41 +0300, Dmitry Frolov wrote:
Enum variable of type qemuMigrationCapability is checked for zero in src/qemu/qemu_migration_params.c:729.
"if (item->optional) { ..."
Actualy, QEMU_MIGRATION_CAP_XBZRLE enum constant has value 0. So, at least, the condition is incorrect.
v1: introducing a separate enum for optional capabilities v2: another approach: fix only the incorrect condition
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Dmitry Frolov <frolov@swemel.ru> --- src/qemu/qemu_migration_params.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/src/qemu/qemu_migration_params.c b/src/qemu/qemu_migration_params.c index c10660d6f2..98d314cf2d 100644 --- a/src/qemu/qemu_migration_params.c +++ b/src/qemu/qemu_migration_params.c @@ -700,6 +700,12 @@ qemuMigrationParamsSetBlockDirtyBitmapMapping(qemuMigrationParams *migParams, ignore_value(virBitmapClearBit(migParams->caps, QEMU_MIGRATION_CAP_BLOCK_DIRTY_BITMAPS)); }
+static bool +qemuMigrationCapabilityIsOptional(qemuMigrationCapability cap) +{ + return cap == QEMU_MIGRATION_CAP_POSTCOPY_PREEMPT || + cap == QEMU_MIGRATION_CAP_SWITCHOVER_ACK; +}
qemuMigrationParams * qemuMigrationParamsFromFlags(virTypedParameterPtr params, @@ -725,7 +731,7 @@ qemuMigrationParamsFromFlags(virTypedParameterPtr params, qemuMigrationCapabilityTypeToString(item->cap)); ignore_value(virBitmapSetBit(migParams->caps, item->cap));
- if (item->optional) { + if (qemuMigrationCapabilityIsOptional(item->optional)) { qemuMigrationCapability opt = item->optional; ignore_value(virBitmapSetBit(migParams->optional, opt)); if (item->party != party)
The issue was that item->optional is initialized to a value that matches one of the capabilities and this patch doesn't do anything with it. The check whether item->optional is non-zero works fine so changing just this check does not make any sense. Jirka