[PATCH -next v13 05/19] riscv: Disable Vector Instructions for kernel itself

[Andy Chiu]

Disable vector instructions execution for kernel mode at its entrances.

Signed-off-by: Guo Ren <guoren at linux.alibaba.com>
Co-developed-by: Vincent Chen <vincent.chen at sifive.com>
Signed-off-by: Vincent Chen <vincent.chen at sifive.com>
Co-developed-by: Han-Kuan Chen <hankuan.chen at sifive.com>
Signed-off-by: Han-Kuan Chen <hankuan.chen at sifive.com>
Co-developed-by: Greentime Hu <greentime.hu at sifive.com>
Signed-off-by: Greentime Hu <greentime.hu at sifive.com>
Signed-off-by: Vineet Gupta <vineetg at rivosinc.com>
[vineetg: split off vecreg file clearing]
Signed-off-by: Andy Chiu <andy.chiu at sifive.com>
---
 arch/riscv/kernel/entry.S |  6 +++---
 arch/riscv/kernel/head.S  | 12 ++++++------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 99d38fdf8b18..e38676d9a0d6 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -77,10 +77,10 @@ _save_context:
 	 * Disable user-mode memory access as it should only be set in the
 	 * actual user copy routines.
 	 *
-	 * Disable the FPU to detect illegal usage of floating point in kernel
-	 * space.
+	 * Disable the FPU/Vector to detect illegal usage of floating point
+	 * or vector in kernel space.
 	 */
-	li t0, SR_SUM | SR_FS
+	li t0, SR_SUM | SR_FS_VS
 
 	REG_L s0, TASK_TI_USER_SP(tp)
 	csrrc s1, CSR_STATUS, t0
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index ea803c96eeff..7cc975ce619d 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -140,10 +140,10 @@ secondary_start_sbi:
 	.option pop
 
 	/*
-	 * Disable FPU to detect illegal usage of
-	 * floating point in kernel space
+	 * Disable FPU & VECTOR to detect illegal usage of
+	 * floating point or vector in kernel space
 	 */
-	li t0, SR_FS
+	li t0, SR_FS_VS
 	csrc CSR_STATUS, t0
 
 	/* Set trap vector to spin forever to help debug */
@@ -234,10 +234,10 @@ pmp_done:
 .option pop
 
 	/*
-	 * Disable FPU to detect illegal usage of
-	 * floating point in kernel space
+	 * Disable FPU & VECTOR to detect illegal usage of
+	 * floating point or vector in kernel space
 	 */
-	li t0, SR_FS
+	li t0, SR_FS_VS
 	csrc CSR_STATUS, t0
 
 #ifdef CONFIG_RISCV_BOOT_SPINWAIT
-- 
2.17.1