From a0a94bc9a68ffad0cecae6dbff53e5486cdb8eb0 Mon Sep 17 00:00:00 2001 From: Stafford Horne Date: Sun, 30 Jan 2022 17:38:51 +0900 Subject: [PATCH] openrisc: Add syscall details to emergency syscall debugging When bringing linux on the or1k Marocchino we ran into issues starting init. This patch adds the syscall number and return address to assist tracing syscalls even before strace is able to be used. By default this is all disabled but a developer could adjust the ifdef to enable debugging. Cc: Andrey Bacherov Signed-off-by: Stafford Horne --- arch/openrisc/kernel/entry.S | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S index 3ca1b1f490b9..54a87bba35ca 100644 --- a/arch/openrisc/kernel/entry.S +++ b/arch/openrisc/kernel/entry.S @@ -601,7 +601,7 @@ UNHANDLED_EXCEPTION(_vector_0xb00,0xb00) */ _string_syscall_return: - .string "syscall return %ld \n\r\0" + .string "syscall r9:0x%08x -> syscall(%ld) return %ld\0" .align 4 ENTRY(_sys_call_handler) @@ -679,15 +679,25 @@ _syscall_return: _syscall_debug: l.movhi r3,hi(_string_syscall_return) l.ori r3,r3,lo(_string_syscall_return) - l.ori r27,r0,1 + l.ori r27,r0,2 l.sw -4(r1),r27 l.sw -8(r1),r11 - l.addi r1,r1,-8 + l.lwz r29,PT_ORIG_GPR11(r1) + l.sw -12(r1),r29 + l.lwz r29,PT_GPR9(r1) + l.sw -16(r1),r29 l.movhi r27,hi(_printk) l.ori r27,r27,lo(_printk) l.jalr r27 - l.nop - l.addi r1,r1,8 + l.addi r1,r1,-16 + l.addi r1,r1,16 +#endif +#if 0 +_syscall_show_regs: + l.movhi r27,hi(show_registers) + l.ori r27,r27,lo(show_registers) + l.jalr r27 + l.or r3,r1,r1 #endif _syscall_check_trace_leave: