From a1409adac748f0db655e096521bbe6904aadeb98 Mon Sep 17 00:00:00 2001
From: Alistair Popple <alistair@popple.id.au>
Date: Wed, 11 Apr 2018 16:38:55 +1000
Subject: [PATCH] powerpc/powernv/npu: Prevent overwriting of
pnv_npu2_init_contex() callback parameters
References: bsc#1055120
Patch-mainline: v4.17-rc3
Git-commit: a1409adac748f0db655e096521bbe6904aadeb98
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: 1ab66d1fbada ("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>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/include/asm/powernv.h | 2 +-
arch/powerpc/platforms/powernv/npu-dma.c | 16 +++++++++++++---
2 files changed, 14 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/include/asm/powernv.h b/arch/powerpc/include/asm/powernv.h
index d1c2d2e658cf..2f3ff7a27881 100644
--- a/arch/powerpc/include/asm/powernv.h
+++ b/arch/powerpc/include/asm/powernv.h
@@ -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);
diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c
index 5ff7c6e0e6da..ccd57d1b5bf8 100644
--- a/arch/powerpc/platforms/powernv/npu-dma.c
+++ b/arch/powerpc/platforms/powernv/npu-dma.c
@@ -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) {
--
2.19.2