powerpc/powernv/npu: Prevent overwriting of pnv_npu2_init_contex() callback parameters

There is a single npu context per set of callback parameters. Callers
should be prevented from overwriting existing callback values so
instead return an error if different parameters are passed.

Fixes: 1ab66d1fba ("powerpc/powernv: Introduce address translation services for Nvlink2")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Reviewed-by: Mark Hairgrove <mhairgrove@nvidia.com>
Tested-by: Mark Hairgrove <mhairgrove@nvidia.com>
Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Alistair Popple 2018-04-11 16:38:55 +10:00 committed by Michael Ellerman
parent 28a5933e8d
commit a1409adac7
2 changed files with 14 additions and 4 deletions

View file

@ -15,7 +15,7 @@
extern void powernv_set_nmmu_ptcr(unsigned long ptcr);
extern struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
unsigned long flags,
struct npu_context *(*cb)(struct npu_context *, void *),
void (*cb)(struct npu_context *, void *),
void *priv);
extern void pnv_npu2_destroy_context(struct npu_context *context,
struct pci_dev *gpdev);

View file

@ -407,7 +407,7 @@ struct npu_context {
bool nmmu_flush;
/* Callback to stop translation requests on a given GPU */
struct npu_context *(*release_cb)(struct npu_context *, void *);
void (*release_cb)(struct npu_context *context, void *priv);
/*
* Private pointer passed to the above callback for usage by
@ -707,7 +707,7 @@ static const struct mmu_notifier_ops nv_nmmu_notifier_ops = {
*/
struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
unsigned long flags,
struct npu_context *(*cb)(struct npu_context *, void *),
void (*cb)(struct npu_context *, void *),
void *priv)
{
int rc;
@ -765,8 +765,18 @@ struct npu_context *pnv_npu2_init_context(struct pci_dev *gpdev,
*/
spin_lock(&npu_context_lock);
npu_context = mm->context.npu_context;
if (npu_context)
if (npu_context) {
if (npu_context->release_cb != cb ||
npu_context->priv != priv) {
spin_unlock(&npu_context_lock);
opal_npu_destroy_context(nphb->opal_id, mm->context.id,
PCI_DEVID(gpdev->bus->number,
gpdev->devfn));
return ERR_PTR(-EINVAL);
}
WARN_ON(!kref_get_unless_zero(&npu_context->kref));
}
spin_unlock(&npu_context_lock);
if (!npu_context) {