[PATCH 0/4] Fix XPU violation during modem metadata authentication

From: Sibi Sankar
Date: Tue Dec 13 2022 - 09:08:08 EST


The memory region allocated using dma_alloc_attr with no kernel mapping
attribute set would still be a part of the linear kernel map. Any access
to this region by the application processor after assigning it to the
remote Q6 will result in a XPU violation. Fix this by replacing the
dynamically allocated memory region with a no-map carveout and unmap the
modem metadata memory region before passing control to the remote Q6.
The addition of the carveout and memunmap is required only on SoCs that
mandate memory protection before transferring control to Q6, hence the
driver falls back to dynamic memory allocation in the absence of the
modem metadata carveout.

Relevant discussions on the mailing list:
https://lore.kernel.org/lkml/20221114110329.68413-1-manivannan.sadhasivam@xxxxxxxxxx/

Depends on:
https://patchwork.kernel.org/project/linux-arm-msm/cover/20221124184333.133911-1-krzysztof.kozlowski@xxxxxxxxxx/

Reported-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
https://people.linaro.org/~amit.pundir/linaro-sid-developer-dragonboard-845c-569/6.1-rc4_defconfig
Reproduced with ^^ defconfig SDM845 SoCs

Sibi Sankar (4):
arm64: dts: qcom: Introduce a carveout for modem metadata
dt-bindings: remoteproc: qcom: sc7180: Update memory-region
requirements
dt-bindings: remoteproc: qcom: q6v5: Update memory region requirements
remoteproc: qcom_q6v5_mss: Use a carveout to authenticate modem
headers

.../bindings/remoteproc/qcom,q6v5.txt | 29 ++++++-
.../remoteproc/qcom,sc7180-mss-pil.yaml | 3 +-
.../remoteproc/qcom,sc7280-mss-pil.yaml | 3 +-
.../boot/dts/qcom/msm8996-xiaomi-common.dtsi | 6 ++
arch/arm64/boot/dts/qcom/msm8996.dtsi | 9 ++
arch/arm64/boot/dts/qcom/msm8998.dtsi | 9 ++
arch/arm64/boot/dts/qcom/sc7180-idp.dts | 7 +-
arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 7 +-
.../dts/qcom/sc7280-herobrine-lte-sku.dtsi | 7 +-
arch/arm64/boot/dts/qcom/sdm845.dtsi | 9 ++
drivers/remoteproc/qcom_q6v5_mss.c | 85 +++++++++++++------
11 files changed, 142 insertions(+), 32 deletions(-)

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2.17.1