[PATCH v3 3/3] PCI: endpoint: Fix API pci_epf_add_vepf() returning -EBUSY error

[Zijun Hu]

From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>

pci_epf_add_vepf() will suffer -EBUSY error by steps below:

pci_epf_add_vepf(@epf_pf, @epf_vf)       // add
pci_epf_remove_vepf(@epf_pf, @epf_vf)   // remove
pci_epf_add_vepf(@epf_pf, @epf_vf)     // add again, -EBUSY error.

Fix by clearing @epf_vf->epf_pf in pci_epf_remove_vepf().

Fixes: 1cf362e907f3 ("PCI: endpoint: Add support to add virtual function in endpoint core")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
---
 drivers/pci/endpoint/pci-epf-core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/pci/endpoint/pci-epf-core.c b/drivers/pci/endpoint/pci-epf-core.c
index 8fa2797d4169a9f21136bbf73daa818da6c4ac49..50bc2892a36c54aa82c819ac5a9c99e9155d92c1 100644
--- a/drivers/pci/endpoint/pci-epf-core.c
+++ b/drivers/pci/endpoint/pci-epf-core.c
@@ -202,6 +202,7 @@ void pci_epf_remove_vepf(struct pci_epf *epf_pf, struct pci_epf *epf_vf)
 
 	mutex_lock(&epf_pf->lock);
 	clear_bit(epf_vf->vfunc_no, &epf_pf->vfunction_num_map);
+	epf_vf->epf_pf = NULL;
 	list_del(&epf_vf->list);
 	mutex_unlock(&epf_pf->lock);
 }

-- 
2.34.1