On Fri, May 01, 2020 at 01:36:17PM +0800, Wei Hu wrote:
> Some error cases in hv_pci_probe() were not handled. Fix these error
> paths to release the resourses and clean up the state properly.
This patch does more than that. It adds a variable to store the
number of slots actually allocated - I presume to free only
allocated on slots on the exit path.
Two patches required I am afraid.
> Signed-off-by: Wei Hu <w...@microsoft.com>
> ---
> drivers/pci/controller/pci-hyperv.c | 20 ++++++++++++++++----
> 1 file changed, 16 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/controller/pci-hyperv.c
> b/drivers/pci/controller/pci-hyperv.c
> index e15022ff63e3..e6fac0187722 100644
> --- a/drivers/pci/controller/pci-hyperv.c
> +++ b/drivers/pci/controller/pci-hyperv.c
> @@ -480,6 +480,9 @@ struct hv_pcibus_device {
>
> struct workqueue_struct *wq;
>
> + /* Highest slot of child device with resources allocated */
> + int wslot_res_allocated;
I don't understand why you need an int rather than a u32.
Furthermore, I think a bitmap is more appropriate for what this
variable is used for.
> +
> /* hypercall arg, must not cross page boundary */
> struct hv_retarget_device_interrupt retarget_msi_interrupt_params;
>
> @@ -2847,7 +2850,7 @@ static int hv_send_resources_allocated(struct hv_device
> *hdev)
> struct hv_pci_dev *hpdev;
> struct pci_packet *pkt;
> size_t size_res;
> - u32 wslot;
> + int wslot;
> int ret;
>
> size_res = (hbus->protocol_version < PCI_PROTOCOL_VERSION_1_2)
> @@ -2900,6 +2903,8 @@ static int hv_send_resources_allocated(struct hv_device
> *hdev)
> comp_pkt.completion_status);
> break;
> }
> +
> + hbus->wslot_res_allocated = wslot;
> }
>
> kfree(pkt);
> @@ -2918,10 +2923,10 @@ static int hv_send_resources_released(struct
> hv_device *hdev)
> struct hv_pcibus_device *hbus = hv_get_drvdata(hdev);
> struct pci_child_message pkt;
> struct hv_pci_dev *hpdev;
> - u32 wslot;
> + int wslot;
> int ret;
>
> - for (wslot = 0; wslot < 256; wslot++) {
> + for (wslot = hbus->wslot_res_allocated; wslot >= 0; wslot--) {
> hpdev = get_pcichild_wslot(hbus, wslot);
> if (!hpdev)
> continue;
> @@ -2936,8 +2941,12 @@ static int hv_send_resources_released(struct hv_device
> *hdev)
> VM_PKT_DATA_INBAND, 0);
> if (ret)
> return ret;
> +
> + hbus->wslot_res_allocated = wslot - 1;
Do you really need to set it at every loop iteration ?
Moreover, I think a bitmap is better suited for what you are doing,
given that you may skip some loop indexes on !hpdev.
> }
>
> + hbus->wslot_res_allocated = -1;
> +
> return 0;
> }
>
> @@ -3037,6 +3046,7 @@ static int hv_pci_probe(struct hv_device *hdev,
> if (!hbus)
> return -ENOMEM;
> hbus->state = hv_pcibus_init;
> + hbus->wslot_res_allocated = -1;
>
> /*
> * The PCI bus "domain" is what is called "segment" in ACPI and other
> @@ -3136,7 +3146,7 @@ static int hv_pci_probe(struct hv_device *hdev,
>
> ret = hv_pci_allocate_bridge_windows(hbus);
> if (ret)
> - goto free_irq_domain;
> + goto exit_d0;
>
> ret = hv_send_resources_allocated(hdev);
> if (ret)
> @@ -3154,6 +3164,8 @@ static int hv_pci_probe(struct hv_device *hdev,
>
> free_windows:
> hv_pci_free_bridge_windows(hbus);
> +exit_d0:
> + (void) hv_pci_bus_exit(hdev, true);
Remove the (void) cast.
Lorenzo
> free_irq_domain:
> irq_domain_remove(hbus->irq_domain);
> free_fwnode:
> --
> 2.20.1
>
