From bcae803a213172c79ab5d077f169e3428e44d2ba Mon Sep 17 00:00:00 2001 From: "zongbox@gmail.com" Date: Mon, 29 Jan 2018 23:51:45 -0800 Subject: 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(-) (limited to 'arch/riscv/kernel') 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 -- cgit v1.3-14-g43fede From 8b08f50152ff85a4780e5c385d2b65889406e842 Mon Sep 17 00:00:00 2001 From: Michael Clark Date: Fri, 16 Feb 2018 09:30:29 +1300 Subject: Rename sbi_save to parse_dtb to improve code readability The sbi_ prefix would seem to indicate an SBI interface, and save is not very specific. After applying this patch, reading head.S makes more sense. Signed-off-by: Michael Clark Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/head.S | 2 +- arch/riscv/kernel/setup.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/riscv/kernel') diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 226eeb190f90..6e07ed37bbff 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -64,7 +64,7 @@ ENTRY(_start) /* Start the kernel */ mv a0, s0 mv a1, s1 - call sbi_save + call parse_dtb tail start_kernel relocate: diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index 09f7064e898c..c11f40c1b2a8 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -144,7 +144,7 @@ asmlinkage void __init setup_vm(void) #endif } -void __init sbi_save(unsigned int hartid, void *dtb) +void __init parse_dtb(unsigned int hartid, void *dtb) { early_init_dt_scan(__va(dtb)); } -- cgit v1.3-14-g43fede