lkml.org 
[lkml]   [2016]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH 1/2 v3] pci-hyperv: properly handle pci bus remove
Date


> -----Original Message-----
> From: Bjorn Helgaas [mailto:helgaas@kernel.org]
> Sent: Friday, November 11, 2016 1:04 PM
> To: Long Li <longli@microsoft.com>
> Cc: KY Srinivasan <kys@microsoft.com>; Haiyang Zhang
> <haiyangz@microsoft.com>; Bjorn Helgaas <bhelgaas@google.com>;
> devel@linuxdriverproject.org; linux-pci@vger.kernel.org; linux-
> kernel@vger.kernel.org; Long Li <longli@microsoft.com>
> Subject: Re: [PATCH 1/2 v3] pci-hyperv: properly handle pci bus remove
>
> On Mon, Oct 03, 2016 at 11:42:47PM -0700, Long Li wrote:
> > From: Long Li <longli@microsoft.com>
> >
> > hv_pci_devices_present is called in hv_pci_remove when we remove a PCI
> device from host (e.g. by disabling SRIOV on a device). In hv_pci_remove,
> the bus is already removed before the call, so we don't need to rescan the
> bus in the workqueue scheduled from hv_pci_devices_present. By
> introducing status hv_pcibus_removed, we can avoid this situation.
> >
> > Signed-off-by: Long Li <longli@microsoft.com>
> > Tested-by: Cathy Avery <cavery@redhat.com>
> > Reported-by: Xiaofeng Wang <xiaofwan@redhat.com>

Acked-by: K. Y. Srinivasan <kys@microsoft.com>


>
> I need an ack from the Hyper-V maintainers. I see acks for previous
> versions, but I don't know whether you've changed things that would
> invalidate those acks. If the acks still apply, please include them
> and repost these patches.
>
> Also, please run "git log --oneline drivers/pci/host/pci-hyperv.c" and make
> your subject line match the previous ones.
>
> > ---
> > drivers/pci/host/pci-hyperv.c | 20 +++++++++++++++++---
> > 1 file changed, 17 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/pci/host/pci-hyperv.c b/drivers/pci/host/pci-hyperv.c
> > index a8deeca..4a37598 100644
> > --- a/drivers/pci/host/pci-hyperv.c
> > +++ b/drivers/pci/host/pci-hyperv.c
> > @@ -348,6 +348,7 @@ enum hv_pcibus_state {
> > hv_pcibus_init = 0,
> > hv_pcibus_probed,
> > hv_pcibus_installed,
> > + hv_pcibus_removed,
> > hv_pcibus_maximum
> > };
> >
> > @@ -1481,13 +1482,24 @@ static void pci_devices_present_work(struct
> work_struct *work)
> > put_pcichild(hpdev, hv_pcidev_ref_initial);
> > }
> >
> > - /* Tell the core to rescan bus because there may have been changes.
> */
> > - if (hbus->state == hv_pcibus_installed) {
> > + switch (hbus->state) {
> > + case hv_pcibus_installed:
> > + /*
> > + * Tell the core to rescan bus
> > + * because there may have been changes.
> > + */
> > pci_lock_rescan_remove();
> > pci_scan_child_bus(hbus->pci_bus);
> > pci_unlock_rescan_remove();
> > - } else {
> > + break;
> > +
> > + case hv_pcibus_init:
> > + case hv_pcibus_probed:
> > survey_child_resources(hbus);
> > + break;
> > +
> > + default:
> > + break;
> > }
> >
> > up(&hbus->enum_sem);
> > @@ -2163,6 +2175,7 @@ static int hv_pci_probe(struct hv_device *hdev,
> > hbus = kzalloc(sizeof(*hbus), GFP_KERNEL);
> > if (!hbus)
> > return -ENOMEM;
> > + hbus->state = hv_pcibus_init;
> >
> > /*
> > * The PCI bus "domain" is what is called "segment" in ACPI and
> > @@ -2305,6 +2318,7 @@ static int hv_pci_remove(struct hv_device *hdev)
> > pci_stop_root_bus(hbus->pci_bus);
> > pci_remove_root_bus(hbus->pci_bus);
> > pci_unlock_rescan_remove();
> > + hbus->state = hv_pcibus_removed;
> > }
> >
> > ret = hv_send_resources_released(hdev);
> > --
> > 1.8.5.6
> >
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-pci" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at
> https://na01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fvger.ke
> rnel.org%2Fmajordomo-
> info.html&data=02%7C01%7Ckys%40microsoft.com%7C982492a275ed4126c4
> d308d40a7644da%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C6361
> 44950466092469&sdata=9cXs6P1zoQ7qB%2BxYD9bsd%2BLMN%2BjwSPQkxnj
> iqBdv9go%3D&reserved=0

\
 
 \ /
  Last update: 2016-11-11 23:54    [W:0.071 / U:0.984 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site