[PATCH] drivers/crypto: Mark QCE as BROKEN

[PATCH] drivers/crypto: Mark QCE as BROKEN

[Demi Marie Obenour via B4 Relay]

From: Demi Marie Obenour <demiobenour@gmail.com>

This driver is harmful:

- It is much slower than the CPU [1] [2].
- It Has a history of bugs [2] [3].
- It does not have exclusive access to the hardware [4], causing races
  with the secure world.
- It register its implementations with too low a cra_priority for them
  to be actually used [5].

Therefore, disable it to ensure that nobody builds it into kernels they
intend to ship.

In the future, the driver will be used for processing restricted media
content.  However, the kernel does not currently support this.  Since
the driver will have future uses, allow building it if COMPILE_TEST is
enabled.

[1]: https://lore.kernel.org/r/20250704070322.20692-1-ebiggers@kernel.org/
[2]: https://lore.kernel.org/r/20250615031807.GA81869@sol/
[3]: https://lore.kernel.org/r/20260706-qce-fix-self-tests-v5-0-86f461ff1829@oss.qualcomm.com/
[4]: https://lore.kernel.org/r/20260629-qcom-qce-cmd-descr-v20-0-56f67da84c05@oss.qualcomm.com/
[5]: https://lore.kernel.org/r/20260524204537.GB110177@quark/

Signed-off-by: Demi Marie Obenour <demiobenour@gmail.com>
---
 arch/arm/configs/multi_v7_defconfig | 1 -
 arch/arm64/configs/defconfig        | 1 -
 drivers/crypto/Kconfig              | 6 +++++-
 3 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index 01e016752c4d425e59a1a499abb8df8845aa9833..13d85a0e8580000235b4dbf6d0911b4e09af199d 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -1321,7 +1321,6 @@ CONFIG_CRYPTO_DEV_ATMEL_AES=m
 CONFIG_CRYPTO_DEV_ATMEL_TDES=m
 CONFIG_CRYPTO_DEV_ATMEL_SHA=m
 CONFIG_CRYPTO_DEV_MARVELL_CESA=m
-CONFIG_CRYPTO_DEV_QCE=m
 CONFIG_CRYPTO_DEV_ROCKCHIP=m
 CONFIG_CRYPTO_DEV_STM32_HASH=m
 CONFIG_CRYPTO_DEV_STM32_CRYP=m
diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 76ce07a08d5ac45bc4a4890c3f1aa7391de346fd..c624cdd122d144ad7e052f965c20c9bdcb3bd2e1 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -1940,7 +1940,6 @@ CONFIG_CRYPTO_AES_ARM64_CE_CCM=y
 CONFIG_CRYPTO_DEV_SUN8I_CE=m
 CONFIG_CRYPTO_DEV_FSL_CAAM=m
 CONFIG_CRYPTO_DEV_FSL_DPAA2_CAAM=m
-CONFIG_CRYPTO_DEV_QCE=m
 CONFIG_CRYPTO_DEV_TEGRA=m
 CONFIG_CRYPTO_DEV_ZYNQMP_AES=m
 CONFIG_CRYPTO_DEV_ZYNQMP_SHA3=m
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 03a8f7a1f75e878846dcf34da1265828949fbd9c..0189dfdcbbe11098ead0ea194293422a31d8fe65 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -528,13 +528,17 @@ source "drivers/crypto/intel/Kconfig"
 
 config CRYPTO_DEV_QCE
 	tristate "Qualcomm crypto engine accelerator"
-	depends on ARCH_QCOM || COMPILE_TEST
+	depends on (BROKEN && ARCH_QCOM) || COMPILE_TEST
 	depends on HAS_IOMEM
 	help
 	  This driver supports Qualcomm crypto engine accelerator
 	  hardware. To compile this driver as a module, choose M here. The
 	  module will be called qcrypto.
 
+	  This driver does not have exclusive access to the
+	  hardware, causing races with the secure world.  It
+	  is also slower than the CPU.
+
 config CRYPTO_DEV_QCE_SKCIPHER
 	bool
 	depends on CRYPTO_DEV_QCE

---
base-commit: e264401ce4776a288524e5b87593d4d864147115
change-id: 20260712-qce-broken-6035863c14a0

Best regards,
-- 
Demi Marie Obenour <demiobenour@gmail.com>