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envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Juraj Marcin If the length of the data sent after CMD_PACKAGED is just right, and there is not much data to send afterward, it is possible part of the CMD_PACKAGED payload will get left behind in the sending buffer. This causes the destination side to hang while it tries to load the whole package and initiate postcopy. Signed-off-by: Juraj Marcin Link: https://lore.kernel.org/r/20251103183301.3840862-2-jmarcin@redhat.com Signed-off-by: Peter Xu --- migration/savevm.c | 1 + 1 file changed, 1 insertion(+) diff --git a/migration/savevm.c b/migration/savevm.c index 232cae090b..fa017378db 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1142,6 +1142,7 @@ int qemu_savevm_send_packaged(QEMUFile *f, const uint8_t *buf, size_t len) qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); qemu_put_buffer(f, buf, len); + qemu_fflush(f); return 0; } -- 2.50.1