[PATCH v2 0/6] arm64: dts: qcom: Remove FastRPC compute CB9 entries

[PATCH v2 0/6] arm64: dts: qcom: Remove FastRPC compute CB9 entries

[Abhinav Parihar]

Context bank 9 (CB9) is reserved for secure use cases and must not be
exposed as a FastRPC compute context bank for non-secure offloading.

Several Qualcomm platform device trees currently define compute-cb@9
nodes, which allows non-secure clients to select a context bank that is
intended for secure use. Remove these CB9 entries from all affected
platforms to prevent unintended usage and align the device trees with
the intended security model.

This series removes the compute-cb@9 nodes from all affected Qualcomm
platform DTSI files.

Patch [v1]: https://lore.kernel.org/all/20261016052042.3755352-1-abhinav.parihar@oss.qualcomm.com/ 

Changes in v2:
- Split the changes from a single patch into a per-platform patch series.
- No functional changes.

Abhinav Parihar (6):
  arm64: dts: qcom: lemans: Remove FastRPC compute CB9 entry
  arm64: dts: qcom: monaco: Remove FastRPC compute CB9 entry
  arm64: dts: qcom: sc8280xp: Remove FastRPC compute CB9 entry
  arm64: dts: qcom: sdm660: Remove FastRPC compute CB9 entry
  arm64: dts: qcom: sdm630: Remove FastRPC compute CB9 entry
  arm64: dts: qcom: msm8996: Remove FastRPC compute CB9 entry

 arch/arm64/boot/dts/qcom/lemans.dtsi   | 16 ----------------
 arch/arm64/boot/dts/qcom/monaco.dtsi   |  7 -------
 arch/arm64/boot/dts/qcom/msm8996.dtsi  |  6 ------
 arch/arm64/boot/dts/qcom/sc8280xp.dtsi |  6 ------
 arch/arm64/boot/dts/qcom/sdm630.dtsi   |  5 -----
 arch/arm64/boot/dts/qcom/sdm660.dtsi   |  6 ------
 6 files changed, 46 deletions(-)

-- 
2.34.1

[PATCH v2 1/6] arm64: dts: qcom: lemans: Remove FastRPC compute CB9 entry

[Abhinav Parihar]

Remove the compute-cb@9 nodes from Lemans device tree to
prevent clients from selecting a secure context bank for normal FastRPC
workloads.

Secure use case support is not currently implemented upstream.

Fixes: f7b01bfb4b47 ("arm64: qcom: sa8775p: Add ADSP and CDSP0 fastrpc nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/lemans.dtsi | 16 ----------------
 1 file changed, 16 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/lemans.dtsi b/arch/arm64/boot/dts/qcom/lemans.dtsi
index 695eae1b7256..5481dfb73454 100644
--- a/arch/arm64/boot/dts/qcom/lemans.dtsi
+++ b/arch/arm64/boot/dts/qcom/lemans.dtsi
@@ -7861,14 +7861,6 @@ compute-cb@8 {
 						dma-coherent;
 					};
 
-					compute-cb@9 {
-						compatible = "qcom,fastrpc-compute-cb";
-						reg = <9>;
-						iommus = <&apps_smmu 0x2149 0x04a0>,
-							 <&apps_smmu 0x2189 0x0400>;
-						dma-coherent;
-					};
-
 					compute-cb@11 {
 						compatible = "qcom,fastrpc-compute-cb";
 						reg = <11>;
@@ -8000,14 +7992,6 @@ compute-cb@8 {
 						dma-coherent;
 					};
 
-					compute-cb@9 {
-						compatible = "qcom,fastrpc-compute-cb";
-						reg = <9>;
-						iommus = <&apps_smmu 0x2949 0x04a0>,
-							 <&apps_smmu 0x2989 0x0400>;
-						dma-coherent;
-					};
-
 					compute-cb@10 {
 						compatible = "qcom,fastrpc-compute-cb";
 						reg = <10>;
-- 
2.34.1

Re: [PATCH v2 1/6] arm64: dts: qcom: lemans: Remove FastRPC compute CB9 entry

[Ekansh Gupta]

On 23-10-2026 14:33, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from Lemans device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: f7b01bfb4b47 ("arm64: qcom: sa8775p: Add ADSP and CDSP0 fastrpc nodes")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>

Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>

Re: [PATCH v2 1/6] arm64: dts: qcom: lemans: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/23/26 11:03 AM, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from Lemans device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: f7b01bfb4b47 ("arm64: qcom: sa8775p: Add ADSP and CDSP0 fastrpc nodes")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
> ---

The documentation doesn't concur this for this platform

Konrad

[PATCH v2 2/6] arm64: dts: qcom: monaco: Remove FastRPC compute CB9 entry

[Abhinav Parihar]

Remove the compute-cb@9 nodes from Monaco device tree to
prevent clients from selecting a secure context bank for normal FastRPC
workloads.

Secure use case support is not currently implemented upstream.

Fixes: af0d19ea5a31 ("arm64: dts: monaco: extend fastrpc compute cb")
Cc: stable@vger.kernel.org
Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/monaco.dtsi | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/monaco.dtsi b/arch/arm64/boot/dts/qcom/monaco.dtsi
index cfe39f923224..e73a735f2f13 100644
--- a/arch/arm64/boot/dts/qcom/monaco.dtsi
+++ b/arch/arm64/boot/dts/qcom/monaco.dtsi
@@ -7822,13 +7822,6 @@ compute-cb@8 {
 						dma-coherent;
 					};
 
-					compute-cb@9 {
-						compatible = "qcom,fastrpc-compute-cb";
-						reg = <9>;
-						iommus = <&apps_smmu 0x19c9 0x0400>;
-						dma-coherent;
-					};
-
 					compute-cb@11 {
 						compatible = "qcom,fastrpc-compute-cb";
 						reg = <0xb>;
-- 
2.34.1

Re: [PATCH v2 2/6] arm64: dts: qcom: monaco: Remove FastRPC compute CB9 entry

[Ekansh Gupta]

On 23-10-2026 14:33, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from Monaco device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: af0d19ea5a31 ("arm64: dts: monaco: extend fastrpc compute cb")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>

Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>

Re: [PATCH v2 2/6] arm64: dts: qcom: monaco: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/23/26 11:03 AM, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from Monaco device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: af0d19ea5a31 ("arm64: dts: monaco: extend fastrpc compute cb")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
> ---

The documentation doesn't concur this for this platform

Konrad

[PATCH v2 3/6] arm64: dts: qcom: sc8280xp: Remove FastRPC compute CB9 entry

[Abhinav Parihar]

Remove the compute-cb@9 nodes from sc8280xp device tree to
prevent clients from selecting a secure context bank for normal FastRPC
workloads.

Secure use case support is not currently implemented upstream.

Fixes: 152d1faf1e2f ("arm64: dts: qcom: add SC8280XP platform")
Cc: stable@vger.kernel.org
Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/sc8280xp.dtsi | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sc8280xp.dtsi b/arch/arm64/boot/dts/qcom/sc8280xp.dtsi
index fbcfd3883bbb..3a26377aac5c 100644
--- a/arch/arm64/boot/dts/qcom/sc8280xp.dtsi
+++ b/arch/arm64/boot/dts/qcom/sc8280xp.dtsi
@@ -6279,12 +6279,6 @@ compute-cb@8 {
 						iommus = <&apps_smmu 0x3188 0x0420>;
 					};
 
-					compute-cb@9 {
-						compatible = "qcom,fastrpc-compute-cb";
-						reg = <9>;
-						iommus = <&apps_smmu 0x318b 0x0420>;
-					};
-
 					compute-cb@10 {
 						compatible = "qcom,fastrpc-compute-cb";
 						reg = <10>;
-- 
2.34.1

Re: [PATCH v2 3/6] arm64: dts: qcom: sc8280xp: Remove FastRPC compute CB9 entry

[Ekansh Gupta]

On 23-10-2026 14:33, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from sc8280xp device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: 152d1faf1e2f ("arm64: dts: qcom: add SC8280XP platform")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>

Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>

Re: [PATCH v2 3/6] arm64: dts: qcom: sc8280xp: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/23/26 11:03 AM, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from sc8280xp device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: 152d1faf1e2f ("arm64: dts: qcom: add SC8280XP platform")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
> ---

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Konrad

Re: [PATCH v2 3/6] arm64: dts: qcom: sc8280xp: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/26/26 12:59 PM, Konrad Dybcio wrote:
> On 10/23/26 11:03 AM, Abhinav Parihar wrote:
>> Remove the compute-cb@9 nodes from sc8280xp device tree to
>> prevent clients from selecting a secure context bank for normal FastRPC
>> workloads.
>>
>> Secure use case support is not currently implemented upstream.
>>
>> Fixes: 152d1faf1e2f ("arm64: dts: qcom: add SC8280XP platform")
>> Cc: stable@vger.kernel.org
>> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
>> ---
> 
> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>

Retracted - the doc says the secure cb is the one whose SID ends 
in 9 (and these should match the reg indices anyway so that needs
a separate fix)

Konrad

[PATCH v2 4/6] arm64: dts: qcom: sdm660: Remove FastRPC compute CB9 entry

[Abhinav Parihar]

Remove the compute-cb@9 nodes from sdm660 device tree to
prevent clients from selecting a secure context bank for normal FastRPC
workloads.

Secure use case support is not currently implemented upstream.

Fixes: 708ab9d3bc5b ("arm64: dts: qcom: sdm660: set cdsp compute-cbs' regs properly")
Cc: stable@vger.kernel.org
Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/sdm660.dtsi | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sdm660.dtsi b/arch/arm64/boot/dts/qcom/sdm660.dtsi
index 0fca9662c64a..723bffc99b67 100644
--- a/arch/arm64/boot/dts/qcom/sdm660.dtsi
+++ b/arch/arm64/boot/dts/qcom/sdm660.dtsi
@@ -386,12 +386,6 @@ compute-cb@8 {
 					iommus = <&cdsp_smmu 8>;
 				};
 
-				compute-cb@9 {
-					compatible = "qcom,fastrpc-compute-cb";
-					reg = <9>;
-					iommus = <&cdsp_smmu 9>;
-				};
-
 				compute-cb@10 {
 					compatible = "qcom,fastrpc-compute-cb";
 					reg = <10>;
-- 
2.34.1

Re: [PATCH v2 4/6] arm64: dts: qcom: sdm660: Remove FastRPC compute CB9 entry

[Ekansh Gupta]

On 23-10-2026 14:33, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from sdm660 device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: 708ab9d3bc5b ("arm64: dts: qcom: sdm660: set cdsp compute-cbs' regs properly")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>

Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>

Re: [PATCH v2 4/6] arm64: dts: qcom: sdm660: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/23/26 11:03 AM, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from sdm660 device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: 708ab9d3bc5b ("arm64: dts: qcom: sdm660: set cdsp compute-cbs' regs properly")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
> ---
>  arch/arm64/boot/dts/qcom/sdm660.dtsi | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sdm660.dtsi b/arch/arm64/boot/dts/qcom/sdm660.dtsi
> index 0fca9662c64a..723bffc99b67 100644
> --- a/arch/arm64/boot/dts/qcom/sdm660.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sdm660.dtsi
> @@ -386,12 +386,6 @@ compute-cb@8 {
>  					iommus = <&cdsp_smmu 8>;
>  				};
>  
> -				compute-cb@9 {
> -					compatible = "qcom,fastrpc-compute-cb";
> -					reg = <9>;
> -					iommus = <&cdsp_smmu 9>;
> -				};

On this platform, it seems like the secure ones are SID 1/2

Konrad

[PATCH v2 5/6] arm64: dts: qcom: sdm630: Remove FastRPC compute CB9 entry

[Abhinav Parihar]

Remove the compute-cb@9 nodes from sdm630 device tree to
prevent clients from selecting a secure context bank for normal FastRPC
workloads.

Secure use case support is not currently implemented upstream.

Fixes: e8e1fb5c703f ("arm64: dts: qcom: sdm630: set adsp compute-cbs' regs properly")
Cc: stable@vger.kernel.org
Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/sdm630.dtsi | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/sdm630.dtsi b/arch/arm64/boot/dts/qcom/sdm630.dtsi
index a41ba0da380b..721885455639 100644
--- a/arch/arm64/boot/dts/qcom/sdm630.dtsi
+++ b/arch/arm64/boot/dts/qcom/sdm630.dtsi
@@ -2483,11 +2483,6 @@ compute-cb@8 {
 						iommus = <&lpass_smmu 8>;
 					};
 
-					compute-cb@9 {
-						compatible = "qcom,fastrpc-compute-cb";
-						reg = <9>;
-						iommus = <&lpass_smmu 9>;
-					};
 				};
 			};
 		};
-- 
2.34.1

Re: [PATCH v2 5/6] arm64: dts: qcom: sdm630: Remove FastRPC compute CB9 entry

[Ekansh Gupta]

On 23-10-2026 14:33, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from sdm630 device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: e8e1fb5c703f ("arm64: dts: qcom: sdm630: set adsp compute-cbs' regs properly")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>

Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>

Re: [PATCH v2 5/6] arm64: dts: qcom: sdm630: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/23/26 11:03 AM, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from sdm630 device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: e8e1fb5c703f ("arm64: dts: qcom: sdm630: set adsp compute-cbs' regs properly")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
> ---
>  arch/arm64/boot/dts/qcom/sdm630.dtsi | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sdm630.dtsi b/arch/arm64/boot/dts/qcom/sdm630.dtsi
> index a41ba0da380b..721885455639 100644
> --- a/arch/arm64/boot/dts/qcom/sdm630.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sdm630.dtsi
> @@ -2483,11 +2483,6 @@ compute-cb@8 {
>  						iommus = <&lpass_smmu 8>;
>  					};
>  
> -					compute-cb@9 {
> -						compatible = "qcom,fastrpc-compute-cb";
> -						reg = <9>;
> -						iommus = <&lpass_smmu 9>;
> -					};

I think 4/5 are secure on LPASS on 630.

Konrad

[PATCH v2 6/6] arm64: dts: qcom: msm8996: Remove FastRPC compute CB9 entry

[Abhinav Parihar]

Remove the compute-cb@9 nodes from msm8996 device tree to
prevent clients from selecting a secure context bank for normal FastRPC
workloads.

Secure use case support is not currently implemented upstream.

Fixes: 1b80b83f893d ("arm64: dts: qcom: msm8996: add fastrpc nodes")
Cc: stable@vger.kernel.org
Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
---
 arch/arm64/boot/dts/qcom/msm8996.dtsi | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/arch/arm64/boot/dts/qcom/msm8996.dtsi b/arch/arm64/boot/dts/qcom/msm8996.dtsi
index 818e5660df91..51ef306c1ce0 100644
--- a/arch/arm64/boot/dts/qcom/msm8996.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8996.dtsi
@@ -3701,12 +3701,6 @@ cb@8 {
 						iommus = <&lpass_q6_smmu 8>;
 					};
 
-					cb@9 {
-						compatible = "qcom,fastrpc-compute-cb";
-						reg = <9>;
-						iommus = <&lpass_q6_smmu 9>;
-					};
-
 					cb@10 {
 						compatible = "qcom,fastrpc-compute-cb";
 						reg = <10>;
-- 
2.34.1

Re: [PATCH v2 6/6] arm64: dts: qcom: msm8996: Remove FastRPC compute CB9 entry

[Ekansh Gupta]

On 23-10-2026 14:33, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from msm8996 device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: 1b80b83f893d ("arm64: dts: qcom: msm8996: add fastrpc nodes")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>

Reviewed-by: Ekansh Gupta <ekansh.gupta@oss.qualcomm.com>

Re: [PATCH v2 6/6] arm64: dts: qcom: msm8996: Remove FastRPC compute CB9 entry

[Konrad Dybcio]

On 10/23/26 11:03 AM, Abhinav Parihar wrote:
> Remove the compute-cb@9 nodes from msm8996 device tree to
> prevent clients from selecting a secure context bank for normal FastRPC
> workloads.
> 
> Secure use case support is not currently implemented upstream.
> 
> Fixes: 1b80b83f893d ("arm64: dts: qcom: msm8996: add fastrpc nodes")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abhinav Parihar <abhinav.parihar@oss.qualcomm.com>
> ---
>  arch/arm64/boot/dts/qcom/msm8996.dtsi | 6 ------
>  1 file changed, 6 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/msm8996.dtsi b/arch/arm64/boot/dts/qcom/msm8996.dtsi
> index 818e5660df91..51ef306c1ce0 100644
> --- a/arch/arm64/boot/dts/qcom/msm8996.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8996.dtsi
> @@ -3701,12 +3701,6 @@ cb@8 {
>  						iommus = <&lpass_q6_smmu 8>;
>  					};
>  
> -					cb@9 {
> -						compatible = "qcom,fastrpc-compute-cb";
> -						reg = <9>;
> -						iommus = <&lpass_q6_smmu 9>;
> -					};

The docs I managed to find suggest the protected SIDs are
2 and 3 on msm8996

Konrad