diff mbox series

[v5,15/15] hw/nvme: Update the initalization place for the AER queue

Message ID 20220217174504.1051716-16-lukasz.maniak@linux.intel.com
State New
Headers show
Series hw/nvme: SR-IOV with Virtualization Enhancements | expand

Commit Message

Lukasz Maniak Feb. 17, 2022, 5:45 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 | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Klaus Jensen Feb. 18, 2022, 6:49 a.m. UTC | #1 
On Feb 17 18:45, 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>

Looks good.

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 a9742cf5051..ae41fced596 100644
--- a/hw/nvme/ctrl.c
+++ b/hw/nvme/ctrl.c
@@ -6182,8 +6182,6 @@  static int nvme_start_ctrl(NvmeCtrl *n)
 
     nvme_set_timestamp(n, 0ULL);
 
-    QTAILQ_INIT(&n->aer_queue);
-
     nvme_select_iocs(n);
 
     return 0;
@@ -6844,6 +6842,7 @@  static void nvme_init_state(NvmeCtrl *n)
     n->features.temp_thresh_hi = NVME_TEMPERATURE_WARNING;
     n->starttime_ms = qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL);
     n->aer_reqs = g_new0(NvmeRequest *, n->params.aerl + 1);
+    QTAILQ_INIT(&n->aer_queue);
 
     list->numcntl = cpu_to_le16(max_vfs);
     for (i = 0; i < max_vfs; i++) {