[PATCH] riscv: vector: only enable interrupts in the first-use trap

[Andy Chiu]

The function irqentry_exit_to_user_mode() must be called with interrupt
disabled. The caller of do_trap_insn_illegal() also assumes running
without interrupts. So, we should turn off interrupts after
riscv_v_first_use_handler() returns.

Fixes: cd054837243b ("riscv: Allocate user's vector context in the first-use trap")
Signed-off-by: Andy Chiu <andy.chiu at sifive.com>
---
 arch/riscv/kernel/traps.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c
index 05ffdcd1424e..1595e246bda1 100644
--- a/arch/riscv/kernel/traps.c
+++ b/arch/riscv/kernel/traps.c
@@ -149,12 +149,18 @@ DO_ERROR_INFO(do_trap_insn_fault,
 
 asmlinkage __visible __trap_section void do_trap_insn_illegal(struct pt_regs *regs)
 {
+	bool handled;
+
 	if (user_mode(regs)) {
 		irqentry_enter_from_user_mode(regs);
 
 		local_irq_enable();
 
-		if (!riscv_v_first_use_handler(regs))
+		handled = riscv_v_first_use_handler(regs);
+
+		local_irq_disable();
+
+		if (!handled)
 			do_trap_error(regs, SIGILL, ILL_ILLOPC, regs->epc,
 				      "Oops - illegal instruction");
 
-- 
2.17.1