> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf Of Dawid 
> Osuchowski
> Sent: Friday, June 7, 2024 5:46 PM
> To: [email protected]
> Cc: Kwan, Ngai-mint <[email protected]>; [email protected]; 
> Chmielewski, Pawel <[email protected]>; Simon Horman 
> <[email protected]>; Polchlopek, Mateusz <[email protected]>; Dawid 
> Osuchowski <[email protected]>
> Subject: [Intel-wired-lan] [PATCH iwl-net v5] ice: Do not get coalesce 
> settings while in reset
>
> From: Ngai-Mint Kwan <[email protected]>
>
> Getting coalesce settings while reset is in progress can cause NULL pointer 
> deference bug.
> If under reset, abort get coalesce for ethtool.
>
> We cannot use ice_wait_for_reset() since both the ethtool handler and the 
> adapter reset flow call rtnl_lock() during operation. If we wait for reset 
> completion inside of an ethtool handling function such as ice_get_coalesce(), 
> the wait will always timeout due to reset being blocked by rtnl_lock() inside 
> of ice_queue_set_napi() (which is called during reset process), and in turn 
> we will always return -EBUSY anyways, with the added hang time of the timeout 
> value.
>
> Fixes: 67fe64d78c43 ("ice: Implement getting and setting ethtool coalesce")
> Signed-off-by: Ngai-Mint Kwan <[email protected]>
> Reviewed-by: Mateusz Polchlopek <[email protected]>
> Signed-off-by: Pawel Chmielewski <[email protected]>
> Reviewed-by: Simon Horman <[email protected]>
> Signed-off-by: Dawid Osuchowski <[email protected]>
> ---
> Changes since v1:
> * Added "Fixes:" tag
> Changes since v2:
> * Rebased over current IWL net branch
> * Confirmed that the issue previously reported for this patch [1] by 
> Himasekhar Reddy Pucha was caused by other, internally tracked issue Changes 
> since v3:
> * Using ice_wait_for_reset() instead of returning -EBUSY Changes since v4:
> * Rebased over current IWL net branch
> * Rollback the use of ice_wait_for_reset() due to rtnl_lock() deadlock issue 
> described in [2] and commit msg
>
> [1] 
> https://lore.kernel.org/netdev/bl0pr11mb3122d70abde6c2acee376073bd...@bl0pr11mb3122.namprd11.prod.outlook.com/
> [2] 
> https://lore.kernel.org/netdev/[email protected]/T/#m1629ecfe88d26551852c5c97982cd10314991422
> ---
>  drivers/net/ethernet/intel/ice/ice_ethtool.c | 3 +++
>  1 file changed, 3 insertions(+)
>

Tested-by: Pucha Himasekhar Reddy <[email protected]> (A 
Contingent worker at Intel)

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