From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail01.adl6.internode.on.net (ipmail01.adl6.internode.on.net [150.101.137.136]) by lists.ozlabs.org (Postfix) with ESMTP id 40S23C6168zF25Q for ; Fri, 20 Apr 2018 13:51:35 +1000 (AEST) From: Alistair Popple To: linuxppc-dev@lists.ozlabs.org Cc: mpe@ellerman.id.au, mhairgrove@nvidia.com, arbab@linux.ibm.com Subject: Re: [PATCH 2/2] powernv/npu: Prevent overwriting of pnv_npu2_init_contex() callback parameters Date: Fri, 20 Apr 2018 13:51:33 +1000 Message-ID: <1662962.d6lkC1eHpm@new-mexico> In-Reply-To: <20180411063855.5451-2-alistair@popple.id.au> References: <20180411063855.5451-1-alistair@popple.id.au> <20180411063855.5451-2-alistair@popple.id.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sorry, forgot to include: Fixes: 1ab66d1fbada ("powerpc/powernv: Introduce address translation services for Nvlink2") Thanks On Wednesday, 11 April 2018 4:38:55 PM AEST Alistair Popple wrote: > 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. > > Signed-off-by: Alistair Popple > --- > 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 dc5f6a5d4575..362ea12a4501 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 cb77162f4e7a..193f43ea3fbc 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 > @@ -705,7 +705,7 @@ 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; > @@ -763,8 +763,18 @@ 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) { >