On May 5 07:48, Klaus Jensen wrote:
> From: Klaus Jensen <[email protected]>
>
> The num_queues device paramater has a slightly confusing meaning because
> it accounts for the admin queue pair which is not really optional.
> Secondly, it is really a maximum value of queues allowed.
>
> Add a new max_ioqpairs parameter that only accounts for I/O queue pairs,
> but keep num_queues for compatibility.
>
> Signed-off-by: Klaus Jensen <[email protected]>
> Reviewed-by: Maxim Levitsky <[email protected]>
> Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
> Reviewed-by: Keith Busch <[email protected]>
> ---
> hw/block/nvme.c | 51 ++++++++++++++++++++++++++++++-------------------
> hw/block/nvme.h | 3 ++-
> 2 files changed, 33 insertions(+), 21 deletions(-)
>
> diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> index 623a88be93dc..3875a5f3dcbf 100644
> --- a/hw/block/nvme.c
> +++ b/hw/block/nvme.c
> @@ -1571,7 +1581,8 @@ static Property nvme_props[] = {
> HostMemoryBackend *),
> DEFINE_PROP_STRING("serial", NvmeCtrl, params.serial),
> DEFINE_PROP_UINT32("cmb_size_mb", NvmeCtrl, params.cmb_size_mb, 0),
> - DEFINE_PROP_UINT32("num_queues", NvmeCtrl, params.num_queues, 64),
> + DEFINE_PROP_UINT32("num_queues", NvmeCtrl, params.num_queues, 0),
> + DEFINE_PROP_UINT32("max_ioqpairs", NvmeCtrl, params.max_ioqpairs, 64),
> DEFINE_PROP_END_OF_LIST(),
> };
>
I noticed that this default of 64 makes the default configuration
unsafe by allowing the cq->cqid < 64 assert in nvme_irq_{,de}assert() to
trigger if the pin-based interrupt logic is used (under SPDK for
instance). The assert protects against undefined behavior caused by
shifting by more than 63 into the 64 bit irq_status variable.
As far as I can tell, the assert, the shift and the size of the
irq_status variable is bogus, so I posted a patch for this in
"hw/block/nvme: fixes for interrupt behavior". Preferably that should go
in before this series.
