4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Long Li <longli@xxxxxxxxxxxxx> [ Upstream commit f286299c1d0ba5e2ca0377610307b370fe178767 ] Unlike SCSI and FC, we don't use multiple channels for IDE. Also fix the calculation for sub-channels. Signed-off-by: Long Li <longli@xxxxxxxxxxxxx> Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/storvsc_drv.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -1725,11 +1725,14 @@ static int storvsc_probe(struct hv_devic max_targets = STORVSC_MAX_TARGETS; max_channels = STORVSC_MAX_CHANNELS; /* - * On Windows8 and above, we support sub-channels for storage. + * On Windows8 and above, we support sub-channels for storage + * on SCSI and FC controllers. * The number of sub-channels offerred is based on the number of * VCPUs in the guest. */ - max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel); + if (!dev_is_ide) + max_sub_channels = + (num_cpus - 1) / storvsc_vcpus_per_sub_channel; } scsi_driver.can_queue = (max_outstanding_req_per_channel *