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Date:   Wed, 27 Jul 2022 19:01:56 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Moshe Shemesh <moshe@nvidia.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Saeed Mahameed <saeedm@nvidia.com>,
        Leon Romanovsky <leon@kernel.org>,
        "Tariq Toukan" <tariqt@nvidia.com>,
        Eric Dumazet <edumazet@google.com>,
        Paolo Abeni <pabeni@redhat.com>, Jiri Pirko <jiri@nvidia.com>,
        <netdev@vger.kernel.org>
Subject: Re: [PATCH net-next 2/9] net: devlink: remove region snapshots list
 dependency on devlink->lock
Message-ID: <20220727190156.0ec856ae@kernel.org>
In-Reply-To: <1658941416-74393-3-git-send-email-moshe@nvidia.com>
References: <1658941416-74393-1-git-send-email-moshe@nvidia.com>
        <1658941416-74393-3-git-send-email-moshe@nvidia.com>
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On Wed, 27 Jul 2022 20:03:29 +0300 Moshe Shemesh wrote:
> From: Jiri Pirko <jiri@nvidia.com>
> 
> After mlx4 driver is converted to do locked reload,
> devlink_region_snapshot_create() may be called from both locked and
> unlocked context.

You need to explain why, tho. What makes region snapshots special? 

> So resolve this by removing dependency on devlink->lock for region
> snapshots list consistency and introduce new mutex to ensure it.

I was hoping to avoid per-subobject locks. What prevents us from
depending on the instance lock here (once the driver is converted)?