* Re: [PATCH] nvme-fabrics: error out to unlock the mutex
2023-06-02 5:37 [PATCH] nvme-fabrics: error out to unlock the mutex Chaitanya Kulkarni
@ 2023-06-02 5:42 ` Julia Lawall
2023-06-02 15:03 ` Christoph Hellwig
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Julia Lawall @ 2023-06-02 5:42 UTC (permalink / raw)
To: Chaitanya Kulkarni
Cc: linux-nvme, kbusch, axboe, hch, sagi, kernel test robot,
Julia Lawall
On Thu, 1 Jun 2023, Chaitanya Kulkarni wrote:
> Currently, in the nvmf_host_add() function, if the nvmf_host_alloc()
> call failed to allocate memory for the host, the code would directly
> return -ENOMEM without unlocking the nvmf_hosts_mutex. This could
> lead to potential issues with mutex synchronization.
>
> Fix that error handling mechanism by jumping to the out_unlock label
> when nvmf_host_alloc() fails. This ensures that the mutex is unlocked
> before returning the error code. The updated code enhances avoids
> possible deadlocks.
>
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Julia Lawall <julia.lawall@inria.fr>
> Closes: https://lore.kernel.org/r/202306020909.MTUEBeIa-lkp@intel.com/
> Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
> ---
> drivers/nvme/host/fabrics.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
> index b1fa27b60917..c4345d1d98aa 100644
> --- a/drivers/nvme/host/fabrics.c
> +++ b/drivers/nvme/host/fabrics.c
> @@ -92,8 +92,10 @@ static struct nvmf_host *nvmf_host_add(const char *hostnqn, uuid_t *id)
> }
>
> host = nvmf_host_alloc(hostnqn, id);
> - if (!host)
> - return ERR_PTR(-ENOMEM);
> + if (!host) {
> + host = ERR_PTR(-ENOMEM);
> + goto out_unlock;
> + }
>
> list_add_tail(&host->list, &nvmf_hosts);
> out_unlock:
Looks good, thanks.
Reviewed-by: Julia Lawall <julia.lawall@inria.fr>
> --
> 2.40.0
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] nvme-fabrics: error out to unlock the mutex
2023-06-02 5:37 [PATCH] nvme-fabrics: error out to unlock the mutex Chaitanya Kulkarni
2023-06-02 5:42 ` Julia Lawall
@ 2023-06-02 15:03 ` Christoph Hellwig
2023-06-04 0:38 ` Max Gurtovoy
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Christoph Hellwig @ 2023-06-02 15:03 UTC (permalink / raw)
To: Chaitanya Kulkarni
Cc: linux-nvme, kbusch, axboe, hch, sagi, kernel test robot,
Julia Lawall
On Thu, Jun 01, 2023 at 10:37:13PM -0700, Chaitanya Kulkarni wrote:
> host = nvmf_host_alloc(hostnqn, id);
> - if (!host)
> - return ERR_PTR(-ENOMEM);
> + if (!host) {
> + host = ERR_PTR(-ENOMEM);
> + goto out_unlock;
> + }
Looks good:
Reviewed-by: Christoph Hellwig <hch@lst.de>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] nvme-fabrics: error out to unlock the mutex
2023-06-02 5:37 [PATCH] nvme-fabrics: error out to unlock the mutex Chaitanya Kulkarni
2023-06-02 5:42 ` Julia Lawall
2023-06-02 15:03 ` Christoph Hellwig
@ 2023-06-04 0:38 ` Max Gurtovoy
2023-06-05 22:40 ` Sagi Grimberg
2023-06-09 15:38 ` Keith Busch
4 siblings, 0 replies; 6+ messages in thread
From: Max Gurtovoy @ 2023-06-04 0:38 UTC (permalink / raw)
To: Chaitanya Kulkarni, linux-nvme
Cc: kbusch, axboe, hch, sagi, kernel test robot, Julia Lawall
On 02/06/2023 8:37, Chaitanya Kulkarni wrote:
> Currently, in the nvmf_host_add() function, if the nvmf_host_alloc()
> call failed to allocate memory for the host, the code would directly
> return -ENOMEM without unlocking the nvmf_hosts_mutex. This could
> lead to potential issues with mutex synchronization.
>
> Fix that error handling mechanism by jumping to the out_unlock label
> when nvmf_host_alloc() fails. This ensures that the mutex is unlocked
> before returning the error code. The updated code enhances avoids
> possible deadlocks.
>
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Julia Lawall <julia.lawall@inria.fr>
> Closes: https://lore.kernel.org/r/202306020909.MTUEBeIa-lkp@intel.com/
> Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
> ---
> drivers/nvme/host/fabrics.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/nvme/host/fabrics.c b/drivers/nvme/host/fabrics.c
> index b1fa27b60917..c4345d1d98aa 100644
> --- a/drivers/nvme/host/fabrics.c
> +++ b/drivers/nvme/host/fabrics.c
> @@ -92,8 +92,10 @@ static struct nvmf_host *nvmf_host_add(const char *hostnqn, uuid_t *id)
> }
>
> host = nvmf_host_alloc(hostnqn, id);
> - if (!host)
> - return ERR_PTR(-ENOMEM);
> + if (!host) {
> + host = ERR_PTR(-ENOMEM);
> + goto out_unlock;
> + }
>
> list_add_tail(&host->list, &nvmf_hosts);
> out_unlock:
Looks good,
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] nvme-fabrics: error out to unlock the mutex
2023-06-02 5:37 [PATCH] nvme-fabrics: error out to unlock the mutex Chaitanya Kulkarni
` (2 preceding siblings ...)
2023-06-04 0:38 ` Max Gurtovoy
@ 2023-06-05 22:40 ` Sagi Grimberg
2023-06-09 15:38 ` Keith Busch
4 siblings, 0 replies; 6+ messages in thread
From: Sagi Grimberg @ 2023-06-05 22:40 UTC (permalink / raw)
To: Chaitanya Kulkarni, linux-nvme
Cc: kbusch, axboe, hch, kernel test robot, Julia Lawall
> Currently, in the nvmf_host_add() function, if the nvmf_host_alloc()
> call failed to allocate memory for the host, the code would directly
> return -ENOMEM without unlocking the nvmf_hosts_mutex. This could
> lead to potential issues with mutex synchronization.
>
> Fix that error handling mechanism by jumping to the out_unlock label
> when nvmf_host_alloc() fails. This ensures that the mutex is unlocked
> before returning the error code. The updated code enhances avoids
> possible deadlocks.
>
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Julia Lawall <julia.lawall@inria.fr>
> Closes: https://lore.kernel.org/r/202306020909.MTUEBeIa-lkp@intel.com/
> Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Can add:
Fixes: f0cebf82004d ("nvme-fabrics: prevent overriding of existing host")
otherwise:
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] nvme-fabrics: error out to unlock the mutex
2023-06-02 5:37 [PATCH] nvme-fabrics: error out to unlock the mutex Chaitanya Kulkarni
` (3 preceding siblings ...)
2023-06-05 22:40 ` Sagi Grimberg
@ 2023-06-09 15:38 ` Keith Busch
4 siblings, 0 replies; 6+ messages in thread
From: Keith Busch @ 2023-06-09 15:38 UTC (permalink / raw)
To: Chaitanya Kulkarni
Cc: linux-nvme, axboe, hch, sagi, kernel test robot, Julia Lawall
Thanks, applied for nvme-6.5.
^ permalink raw reply [flat|nested] 6+ messages in thread