> -----Original Message-----
> From: Intel-wired-lan <intel-wired-lan-boun...@osuosl.org> On Behalf Of
> Tarun K Singh
> Sent: Tuesday, November 5, 2024 10:49 AM
> To: intel-wired-...@lists.osuosl.org
> Cc: net...@vger.kernel.org
> Subject: [Intel-wired-lan] [PATCH iwl-net v1 3/4] idpf: Add init, reinit, and
> deinit control lock
>
> Add new 'vport_init_lock' to prevent locking issue.
>
> The existing 'vport_cfg_lock' was controlling the vport initialization,
> re-initialization due to reset, and de-initialization of code flow.
> In addition to controlling the above behavior it was also controlling
> the parallel netdevice calls such as open/close from Linux OS, which
> can happen independent of re-init or de-init of the vport(s). If first
> one such as re-init or de-init is going on then the second operation
> to config the netdevice with OS should not take place. The first
> operation (init or de-init) takes the precedence if both are to happen
> simultaneously.
>
> Use of single lock cause deadlock and inconsistent behavior of code
> flow. E.g. when driver undergoes reset via 'idpf_init_hard_reset', it
> acquires the 'vport_cfg_lock', and during this process it tries to
> unregister netdevice which may call 'idpf_stop' which tries to acquire
> same lock causing it to deadlock.
>
> To address above, add new lock 'vport_init_lock' which control the
> initialization, re-initialization, and de-initialization flow.
> The 'vport_cfg_lock' now exclusively controls the vport config
> operations.
>
> Add vport config lock around 'idpf_vport_stop()' and 'idpf_vport_open()'
> to protect close and open operation at the same time.
>
> Add vport init lock around 'idpf_sriv_configure()' to protect it from
> load and removal path. To accomplish it, use existing function
> as wrapper and introduce another function 'idpf_sriov_config_vfs'
> which is used inside the lock.
>
> In idpf_remove, change 'idpf_sriov_configure' to
> 'idpf_sriov_config_vfs', and move inside the init lock.
>
> Use these two locks in the following precedence:
> 'vport_init_lock' first, then 'vport_cfg_lock'.
>
> Fixes: 8077c727561a ("idpf: add controlq init and reset checks")
> Reviewed-by: Przemek Kitszel <przemyslaw.kits...@intel.com>
> Reviewed-by: Madhu Chittim <madhu.chit...@intel.com>
> Signed-off-by: Tarun K Singh <tarun.k.si...@intel.com>
> ---
> drivers/net/ethernet/intel/idpf/idpf.h | 25 +++++++++++++
> drivers/net/ethernet/intel/idpf/idpf_lib.c | 41 ++++++++++++++++++---
> drivers/net/ethernet/intel/idpf/idpf_main.c | 7 +++-
> 3 files changed, 67 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/idpf/idpf.h
> b/drivers/net/ethernet/intel/idpf/idpf.h
> index 8dea2dd784af..34dbdc7d6c88 100644
> --- a/drivers/net/ethernet/intel/idpf/idpf.h
> +++ b/drivers/net/ethernet/intel/idpf/idpf.h
Tested-by: Krishneil Singh <krishneil.k.si...@intel.com>
