From bcae803a213172c79ab5d077f169e3428e44d2ba Mon Sep 17 00:00:00 2001 From: "zongbox@gmail.com" Date: Mon, 29 Jan 2018 23:51:45 -0800 Subject: [PATCH] RISC-V: Enable IRQ during exception handling Interrupt is allowed during exception handling. There are warning messages if the kernel enables the configuration 'CONFIG_DEBUG_ATOMIC_SLEEP=y'. BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:23 in_atomic(): 0, irqs_disabled(): 1, pid: 43, name: ash CPU: 0 PID: 43 Comm: ash Tainted: G W 4.15.0-rc8-00089-g89ffdae-dirty #17 Call Trace: [<000000009abb1587>] walk_stackframe+0x0/0x7a [<00000000d4f3d088>] ___might_sleep+0x102/0x11a [<00000000b1fd792a>] down_read+0x18/0x28 [<000000000289ec01>] do_page_fault+0x86/0x2f6 [<00000000012441f6>] _do_fork+0x1b4/0x1e0 [<00000000f46c3e3b>] ret_from_syscall+0xa/0xe Reviewed-by: Christoph Hellwig Signed-off-by: Zong Li Signed-off-by: Palmer Dabbelt Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/entry.S | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 87fc045be51f..56fa592cfa34 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -172,6 +172,9 @@ ENTRY(handle_exception) move a1, sp /* pt_regs */ tail do_IRQ 1: + /* Exceptions run with interrupts enabled */ + csrs sstatus, SR_SIE + /* Handle syscalls */ li t0, EXC_SYSCALL beq s4, t0, handle_syscall @@ -198,8 +201,6 @@ handle_syscall: */ addi s2, s2, 0x4 REG_S s2, PT_SEPC(sp) - /* System calls run with interrupts enabled */ - csrs sstatus, SR_SIE /* Trace syscalls, but only if requested by the user. */ REG_L t0, TASK_TI_FLAGS(tp) andi t0, t0, _TIF_SYSCALL_TRACE -- 2.30.2