diff mbox series

[v4,15/15] hw/nvme: Update the initalization place for the AER queue

Message ID 20220126171120.2939152-16-lukasz.maniak@linux.intel.com
State New
Headers show
Series hw/nvme: SR-IOV with Virtualization Enhancements | expand

Commit Message

Lukasz Maniak Jan. 26, 2022, 5:11 p.m. UTC 
From: Łukasz Gieryk <lukasz.gieryk@linux.intel.com>

This patch updates the initialization place for the AER queue, so it’s
initialized once, at controller initialization, and not every time
controller is enabled.

While the original version works for a non-SR-IOV device, as it’s hard
to interact with the controller if it’s not enabled, the multiple
reinitialization is not necessarily correct.

With the SR/IOV feature enabled a segfault can happen: a VF can have its
controller disabled, while a namespace can still be attached to the
controller through the parent PF. An event generated in such case ends
up on an uninitialized queue.

While it’s an interesting question whether a VF should support AER in
the first place, I don’t think it must be answered today.

Signed-off-by: Łukasz Gieryk <lukasz.gieryk@linux.intel.com>
---
 hw/nvme/ctrl.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Klaus Jensen Feb. 11, 2022, 7:43 a.m. UTC | #1 
On Jan 26 18:11, Lukasz Maniak wrote:
> From: Łukasz Gieryk <lukasz.gieryk@linux.intel.com>
> 
> This patch updates the initialization place for the AER queue, so it’s
> initialized once, at controller initialization, and not every time
> controller is enabled.
> 
> While the original version works for a non-SR-IOV device, as it’s hard
> to interact with the controller if it’s not enabled, the multiple
> reinitialization is not necessarily correct.
> 
> With the SR/IOV feature enabled a segfault can happen: a VF can have its
> controller disabled, while a namespace can still be attached to the
> controller through the parent PF. An event generated in such case ends
> up on an uninitialized queue.
> 
> While it’s an interesting question whether a VF should support AER in
> the first place, I don’t think it must be answered today.
> 
> Signed-off-by: Łukasz Gieryk <lukasz.gieryk@linux.intel.com>
> ---
>  hw/nvme/ctrl.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
> index 624db2f9c6..b2228e960f 100644
> --- a/hw/nvme/ctrl.c
> +++ b/hw/nvme/ctrl.c
> @@ -6029,8 +6029,6 @@ static int nvme_start_ctrl(NvmeCtrl *n)
>  
>      nvme_set_timestamp(n, 0ULL);
>  
> -    QTAILQ_INIT(&n->aer_queue);
> -
>      nvme_select_iocs(n);
>  
>      return 0;
> @@ -7007,6 +7005,8 @@ static void nvme_init_ctrl(NvmeCtrl *n, PCIDevice *pci_dev)
>          id->cmic |= NVME_CMIC_MULTI_CTRL;
>      }
>  
> +    QTAILQ_INIT(&n->aer_queue);
> +
>      NVME_CAP_SET_MQES(cap, 0x7ff);
>      NVME_CAP_SET_CQR(cap, 1);
>      NVME_CAP_SET_TO(cap, 0xf);
> -- 
> 2.25.1
> 

Fix is good, but I think this belongs in nvme_init_state(). Otherwise,

Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
diff mbox series

Patch

diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c
index 624db2f9c6..b2228e960f 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -6029,8 +6029,6 @@  static int nvme_start_ctrl(NvmeCtrl *n)
 
     nvme_set_timestamp(n, 0ULL);
 
-    QTAILQ_INIT(&n->aer_queue);
-
     nvme_select_iocs(n);
 
     return 0;
@@ -7007,6 +7005,8 @@  static void nvme_init_ctrl(NvmeCtrl *n, PCIDevice *pci_dev)
         id->cmic |= NVME_CMIC_MULTI_CTRL;
     }
 
+    QTAILQ_INIT(&n->aer_queue);
+
     NVME_CAP_SET_MQES(cap, 0x7ff);
     NVME_CAP_SET_CQR(cap, 1);
     NVME_CAP_SET_TO(cap, 0xf);