This is a note to let you know that I've just added the patch titled ARM: 9075/1: kernel: Fix interrupted SMC calls to the 4.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm-9075-1-kernel-fix-interrupted-smc-calls.patch and it can be found in the queue-4.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit d6e8031d26ef1ee9e921c86758b30e1d085d9259 Author: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Date: Wed Apr 14 04:41:16 2021 +0100 ARM: 9075/1: kernel: Fix interrupted SMC calls [ Upstream commit 57ac51667d8cd62731223d687e5fe7b41c502f89 ] On Qualcomm ARM32 platforms, the SMC call can return before it has completed. If this occurs, the call can be restarted, but it requires using the returned session ID value from the interrupted SMC call. The ARM32 SMCC code already has the provision to add platform specific quirks for things like this. So let's make use of it and add the Qualcomm specific quirk (ARM_SMCCC_QUIRK_QCOM_A6) used by the QCOM_SCM driver. This change is similar to the below one added for ARM64 a while ago: commit 82bcd087029f ("firmware: qcom: scm: Fix interrupted SCM calls") Without this change, the Qualcomm ARM32 platforms like SDX55 will return -EINVAL for SMC calls used for modem firmware loading and validation. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index ae85f67a6352..40afe953a0e2 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -30,6 +30,7 @@ #include <asm/vdso_datapage.h> #include <asm/hardware/cache-l2x0.h> #include <linux/kbuild.h> +#include <linux/arm-smccc.h> #include "signal.h" /* @@ -159,6 +160,8 @@ int main(void) DEFINE(SLEEP_SAVE_SP_PHYS, offsetof(struct sleep_save_sp, save_ptr_stash_phys)); DEFINE(SLEEP_SAVE_SP_VIRT, offsetof(struct sleep_save_sp, save_ptr_stash)); #endif + DEFINE(ARM_SMCCC_QUIRK_ID_OFFS, offsetof(struct arm_smccc_quirk, id)); + DEFINE(ARM_SMCCC_QUIRK_STATE_OFFS, offsetof(struct arm_smccc_quirk, state)); BLANK(); DEFINE(DMA_BIDIRECTIONAL, DMA_BIDIRECTIONAL); DEFINE(DMA_TO_DEVICE, DMA_TO_DEVICE); diff --git a/arch/arm/kernel/smccc-call.S b/arch/arm/kernel/smccc-call.S index e5d43066b889..13d307cd364c 100644 --- a/arch/arm/kernel/smccc-call.S +++ b/arch/arm/kernel/smccc-call.S @@ -12,7 +12,9 @@ * */ #include <linux/linkage.h> +#include <linux/arm-smccc.h> +#include <asm/asm-offsets.h> #include <asm/opcodes-sec.h> #include <asm/opcodes-virt.h> #include <asm/unwind.h> @@ -36,7 +38,14 @@ UNWIND( .fnstart) UNWIND( .save {r4-r7}) ldm r12, {r4-r7} \instr - pop {r4-r7} + ldr r4, [sp, #36] + cmp r4, #0 + beq 1f // No quirk structure + ldr r5, [r4, #ARM_SMCCC_QUIRK_ID_OFFS] + cmp r5, #ARM_SMCCC_QUIRK_QCOM_A6 + bne 1f // No quirk present + str r6, [r4, #ARM_SMCCC_QUIRK_STATE_OFFS] +1: pop {r4-r7} ldr r12, [sp, #(4 * 4)] stm r12, {r0-r3} bx lr