powerpc/powernv/ioda: Protect PE list

Protect the PHB's list of PE. Probably not needed as long as it was
populated during PHB creation, but it feels right and will become
required once we can add/remove opencapi devices on hotplug.

Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191121134918.7155-3-fbarrat@linux.ibm.com

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 82e81fe83637c91aca1b9bc2976a826f752e5608..4bf67d8a3385ea3a69b880159b8d9eb083b6d8fd 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -1087,8 +1087,9 @@ static struct pnv_ioda_pe *pnv_ioda_setup_dev_PE(struct pci_dev *dev)
        }
 
        /* Put PE to the list */
+       mutex_lock(&phb->ioda.pe_list_mutex);
        list_add_tail(&pe->list, &phb->ioda.pe_list);
-
+       mutex_unlock(&phb->ioda.pe_list_mutex);
        return pe;
 }
 
@@ -3528,7 +3529,10 @@ static void pnv_ioda_release_pe(struct pnv_ioda_pe *pe)
        struct pnv_phb *phb = pe->phb;
        struct pnv_ioda_pe *slave, *tmp;
 
+       mutex_lock(&phb->ioda.pe_list_mutex);
        list_del(&pe->list);
+       mutex_unlock(&phb->ioda.pe_list_mutex);
+
        switch (phb->type) {
        case PNV_PHB_IODA1:
                pnv_pci_ioda1_release_pe_dma(pe);