[xen master] xen/riscv: disable fpu

[patchbot@xxxxxxx]

commit d1e67674591c262e7cedfcd42547a3f64caec251
Author:     Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
AuthorDate: Mon Mar 20 17:10:34 2023 +0100
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Mon Mar 20 17:10:34 2023 +0100

    xen/riscv: disable fpu
    
    Disable FPU to detect illegal usage of floating point in kernel
    space.
    
    Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
    Acked-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    Reviewed-by: Bobby Eshleman <bobbyeshleman@xxxxxxxxx>
---
 xen/arch/riscv/riscv64/head.S | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/xen/arch/riscv/riscv64/head.S b/xen/arch/riscv/riscv64/head.S
index ffd95f9f89..52fa41c778 100644
--- a/xen/arch/riscv/riscv64/head.S
+++ b/xen/arch/riscv/riscv64/head.S
@@ -6,6 +6,13 @@ ENTRY(start)
         /* Mask all interrupts */
         csrw    CSR_SIE, zero
 
+        /*
+         * Disable FPU to detect illegal usage of
+         * floating point in kernel space
+         */
+        li      t0, SSTATUS_FS
+        csrc    CSR_SSTATUS, t0
+
         la      sp, cpu0_boot_stack
         li      t0, STACK_SIZE
         add     sp, sp, t0
--
generated by git-patchbot for /home/xen/git/xen.git#master