After calling napi_complete_done(), the NAPIF_STATE_SCHED bit may be
cleared, and another CPU can start napi thread and access per-CQ variable,
cq->work_done. If the other thread (for example, from busy_poll) sets
it to a value >= budget, this thread will continue to run when it should
stop, and cause memory corruption and panic.
To fix this issue, save the per-CQ work_done variable in a local variable
before napi_complete_done(), so it won't be corrupted by a possible
concurrent thread after napi_complete_done().
Also, add a flag bit to advertise to the NIC firmware: the NAPI work_done
variable race is fixed, so the driver is able to reliably support features
like busy_poll.
Cc: stable@vger.kernel.org
Fixes: e1b5683ff6 ("net: mana: Move NAPI from EQ to CQ")
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Link: https://lore.kernel.org/r/1670010190-28595-1-git-send-email-haiyangz@microsoft.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This minimal PF driver runs on bare metal.
Currently Ethernet TX/RX works. SR-IOV management is not supported yet.
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Co-developed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The existing code uses (1 + #vPorts * #Queues) MSIXs, which may exceed
the device limit.
Support EQ sharing, so that multiple vPorts (NICs) can share the same
set of MSIXs.
And, report the EQ-sharing capability bit to the host, which means the
host can potentially offer more vPorts and queues to the VM.
Also update the resource limit checking and error handling for better
robustness.
Now, we support up to 256 virtual ports per VF (it was 16/VF), and
support up to 64 queues per vPort (it was 16).
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The existing code has NAPI threads polling on EQ directly. To prepare
for EQ sharing among vPorts, move NAPI from EQ to CQ so that one EQ
can serve multiple CQs from different vPorts.
The "arm bit" is only set when CQ processing is completed to reduce
the number of EQ entries, which in turn reduce the number of interrupts
on EQ.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a VF driver for Microsoft Azure Network Adapter (MANA) that will be
available in the future.
Co-developed-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Co-developed-by: Shachar Raindel <shacharr@microsoft.com>
Signed-off-by: Shachar Raindel <shacharr@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
