Re: [PATCH] drm/msm/dpu: add DSC range checking during resource reservation

From: Dmitry Baryshkov
Date: Tue Apr 11 2023 - 18:22:08 EST


On 12/04/2023 00:09, Kuogee Hsieh wrote:
Perform DSC range checking to make sure correct DSC is requested before
reserve resource for it.

Fixes: c985d7bb64ff ("drm/msm/disp/dpu1: Add DSC support in RM")

$ git log -p -1 c985d7bb64ff
fatal: ambiguous argument 'c985d7bb64ff': unknown revision or path not in the working tree.

I assume this was generated against some internal tree. Please. Please. Don't do this again. I hoped that this was pointed out ages ago, but probably not. No fixes, commits, tests against internal trees, no matter how precious they are to you.

Signed-off-by: Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
index f4dda88..95e58f1 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_rm.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2016-2018, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2023 Qualcomm Innovation Center, Inc. All rights reserved.
*/
#define pr_fmt(fmt) "[drm:%s] " fmt, __func__
@@ -250,6 +251,11 @@ int dpu_rm_init(struct dpu_rm *rm,
struct dpu_hw_dsc *hw;
const struct dpu_dsc_cfg *dsc = &cat->dsc[i];
+ if (dsc->id < DSC_0 || dsc->id >= DSC_MAX) {
+ DPU_ERROR("skip dsc %d with invalid id\n", dsc->id);
+ continue;
+ }
+
hw = dpu_hw_dsc_init(dsc->id, mmio, cat);
if (IS_ERR_OR_NULL(hw)) {
rc = PTR_ERR(hw);
@@ -557,8 +563,10 @@ static int _dpu_rm_make_reservation(
}
ret = _dpu_rm_reserve_dsc(rm, global_state, enc, &reqs->topology);
- if (ret)
+ if (ret) {
+ DPU_ERROR("unable to find appropriate DSC\n");
return ret;
+ }
return ret;
}

--
With best wishes
Dmitry