Re: [PATCH net] devlink: Hold devlink lock on health reporter dump get

[Moshe Shemesh <moshe@nvidia.com>]

On 10/5/2023 2:39 AM, Jakub Kicinski wrote:
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> 
> 
> On Sun, 1 Oct 2023 18:19:40 +0300 Moshe Shemesh wrote:
>> Devlink health dump get callback should take devlink lock as any other
>> devlink callback. Add devlink lock to the callback and to any call for
>> devlink_health_do_dump().
>>
>> As devlink lock is added to any callback of dump, the reporter dump_lock
>> is now redundant and can be removed.
> 
> I love the change but it needs more info in the commit message :)
> 
>   1. what exact / example but real problem are you solving?

Sure, will send v2

>   2. some words of reassurance that you checked all the drivers
>      and the locking change should be safe (none of them take
>      instance locks in reporter callbacks etc)

That's what I checked, looking at the code, I didn't find any devlink 
instance lock through all drivers health dump callbacks in current code: 
bnxt_fw_dump(), hinic_hw_reporter_dump(), hinic_fw_reporter_dump(), 
rvu_hw_nix_intr_dump() , rvu_hw_nix_gen_dump(), rvu_hw_nix_err_dump(), 
rvu_hw_nix_ras_dump(), rvu_hw_npa_intr_dump(), rvu_hw_npa_gen_dump(), 
rvu_hw_npa_err_dump(), rvu_hw_npa_ras_dump(), 
mlxsw_core_health_fw_fatal_dump(), mlx5e_rx_reporter_dump(), 
mlx5e_tx_reporter_dump(), mlx5_fw_reporter_dump(), 
mlx5_fw_fatal_reporter_dump(), qed_fw_fatal_reporter_dump(), 
nsim_dev_empty_reporter_dump(), nsim_dev_dummy_reporter_dump(), 
qlge_reporter_coredump()


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