Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 128731bb authored by Akhil P Oommen's avatar Akhil P Oommen Committed by Kaushal Sanadhya
Browse files

msm: kgsl: Keep postamble packets in a privileged buffer 



Postamble packets are executed in privileged mode by gpu. So we should keep
them in a privileged scratch buffer to block userspace access. For
targets with APRIV feature support, we can mark the preemption scratch
buffer as privileged too to avoid similar issues in future.

Change-Id: Ifda360dda251083f38dfde80ce1b5dc83daae902
Signed-off-by: default avatarAkhil P Oommen <quic_akhilpo@quicinc.com>
Signed-off-by: default avatarKaushal Sanadhya <quic_ksanadhy@quicinc.com>
parent 29910cbf

drivers/gpu/msm/adreno.h

+1 −4
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Copyright (c) 2008-2021, The Linux Foundation. All rights reserved.

 * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.

 * Copyright (c) 2022-2023, Qualcomm Innovation Center, Inc. All rights reserved.

 */

#ifndef __ADRENO_H

#define __ADRENO_H
@@ -16,9 +16,6 @@ 
#include "adreno_ringbuffer.h"

#include "kgsl_sharedmem.h"



/* Index to preemption scratch buffer to store KMD postamble */

#define KMD_POSTAMBLE_IDX 100



/* ADRENO_DEVICE - Given a kgsl_device return the adreno device struct */

#define ADRENO_DEVICE(device) \

		container_of(device, struct adreno_device, dev)

drivers/gpu/msm/adreno_a6xx_preempt.c

+9 −8
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/*

 * Copyright (c) 2017-2020, The Linux Foundation. All rights reserved.

 * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.

 * Copyright (c) 2022-2023, Qualcomm Innovation Center, Inc. All rights reserved.

 */



#include "adreno.h"
@@ -553,8 +553,7 @@ unsigned int a6xx_preemption_pre_ibsubmit( 


		/* Add a KMD post amble to clear the perf counters during preemption */

		if (!adreno_dev->perfcounter) {

			u64 kmd_postamble_addr =

					PREEMPT_SCRATCH_ADDR(adreno_dev, KMD_POSTAMBLE_IDX);

			u64 kmd_postamble_addr = SCRATCH_POSTAMBLE_ADDR(KGSL_DEVICE(adreno_dev));



			*cmds++ = cp_type7_packet(CP_SET_AMBLE, 3);

			*cmds++ = lower_32_bits(kmd_postamble_addr);
@@ -695,6 +694,7 @@ static int a6xx_preemption_ringbuffer_init(struct adreno_device *adreno_dev, 


int a6xx_preemption_init(struct adreno_device *adreno_dev)

{

	u32 flags = ADRENO_FEATURE(adreno_dev, ADRENO_APRIV) ? KGSL_MEMDESC_PRIVILEGED : 0;

	struct kgsl_device *device = KGSL_DEVICE(adreno_dev);

	struct kgsl_iommu *iommu = KGSL_IOMMU_PRIV(device);

	struct adreno_preemption *preempt = &adreno_dev->preempt;
@@ -717,7 +717,7 @@ int a6xx_preemption_init(struct adreno_device *adreno_dev) 


	if (IS_ERR_OR_NULL(preempt->scratch)) {

		preempt->scratch = kgsl_allocate_global(device, PAGE_SIZE,

			0, 0, 0, "preempt_scratch");

			0, 0, flags, "preempt_scratch");

		if (IS_ERR(preempt->scratch))

			return PTR_ERR(preempt->scratch);

	}
@@ -733,12 +733,13 @@ int a6xx_preemption_init(struct adreno_device *adreno_dev) 
		return ret;



	/*

	 * First 8 dwords of the preemption scratch buffer is used to store the address for CP

	 * to save/restore VPC data. Reserve 11 dwords in the preemption scratch buffer from

	 * index KMD_POSTAMBLE_IDX for KMD postamble pm4 packets

	 * First 28 dwords of the device scratch buffer are used to store shadow rb data.

	 * Reserve 11 dwords in the device scratch buffer from SCRATCH_POSTAMBLE_OFFSET for

	 * KMD postamble pm4 packets. This should be in *device->scratch* so that userspace

	 * cannot access it.

	 */

	if (!adreno_dev->perfcounter) {

		u32 *postamble = preempt->scratch->hostptr + (KMD_POSTAMBLE_IDX * sizeof(u64));

		u32 *postamble = device->scratch->hostptr + SCRATCH_POSTAMBLE_OFFSET;

		u32 count = 0;



		postamble[count++] = cp_type7_packet(CP_REG_RMW, 3);

drivers/gpu/msm/kgsl.h

+6 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Copyright (c) 2008-2021, The Linux Foundation. All rights reserved.

 * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.

 */

#ifndef __KGSL_H

#define __KGSL_H
@@ -71,6 +72,11 @@ 
#define SCRATCH_RPTR_GPU_ADDR(dev, id) \

	((dev)->scratch->gpuaddr + SCRATCH_RPTR_OFFSET(id))



/* OFFSET to KMD postamble packets in scratch buffer */

#define SCRATCH_POSTAMBLE_OFFSET (100 * sizeof(u64))

#define SCRATCH_POSTAMBLE_ADDR(dev) \

	((dev)->scratch->gpuaddr + SCRATCH_POSTAMBLE_OFFSET)



/* Timestamp window used to detect rollovers (half of integer range) */

#define KGSL_TIMESTAMP_WINDOW 0x80000000