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c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1762194801; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=FTL58dGcslqhpWl8jCgH73Dkh0Rme7iehdt9ug/4Lds=; b=NG+XAiqrL+vqbn8RXsN/0sSyzbQutCzzvbRDOdK7LT2HQgBs4dWnCiNBKhKXBk37k+0v/4 QXPrgJv97zl83+4SnPKqvlkaLGnhWKV2eHFaTOn7MYqIZGUgnd/XzgfwbA4WBuoCUaVGdl qg9Mp3d3qLMqPKQy8yq5Sj5uy5rdMHQ= X-MC-Unique: CATjP8I_N_2V3Gs9DdNXLQ-1 X-Mimecast-MFC-AGG-ID: CATjP8I_N_2V3Gs9DdNXLQ_1762194796 From: Juraj Marcin To: qemu-devel@nongnu.org Cc: Juraj Marcin , "Dr. David Alan Gilbert" , Fabiano Rosas , Peter Xu , Jiri Denemark Subject: [PATCH v4 1/8] migration: Flush migration channel after sending data of CMD_PACKAGED Date: Mon, 3 Nov 2025 19:32:50 +0100 Message-ID: <20251103183301.3840862-2-jmarcin@redhat.com> In-Reply-To: <20251103183301.3840862-1-jmarcin@redhat.com> References: <20251103183301.3840862-1-jmarcin@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; 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charset="utf-8" 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 Reviewed-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 uint= 8_t *buf, size_t len) qemu_savevm_command_send(f, MIG_CMD_PACKAGED, 4, (uint8_t *)&tmp); =20 qemu_put_buffer(f, buf, len); + qemu_fflush(f); =20 return 0; } --=20 2.51.0