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[ Upstream commitafb373ff3f] The IO subsystem expects a driver to retry a ccw_device_start, when the subsequent interrupt response block (irb) contains a deferred condition code 1. Symptoms before this commit: On the read channel we always trigger the next read anyhow, so no different behaviour here. On the write channel we may experience timeout errors, because the expected reply will never be received without the retry. Other callers of qeth_send_control_data() may wrongly assume that the ccw was successful, which may cause problems later. Note that since commit2297791c92("s390/cio: dont unregister subchannel from child-drivers") and commit5ef1dc40ff("s390/cio: fix invalid -EBUSY on ccw_device_start") deferred CC1s are much more likely to occur. See the commit message of the latter for more background information. Fixes:2297791c92("s390/cio: dont unregister subchannel from child-drivers") Signed-off-by: Alexandra Winter <wintera@linux.ibm.com> Co-developed-by: Thorsten Winkler <twinkler@linux.ibm.com> Signed-off-by: Thorsten Winkler <twinkler@linux.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com> Link: https://lore.kernel.org/r/20240321115337.3564694-1-wintera@linux.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>