From a9a6e7a09598013ff97e34ebd84c39d1f51f261a Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Thu, 23 May 2013 14:31:23 +0000 Subject: [PATCH] MIPS: Trap exception handling fixes 2a0b24f56c2492b932f1aed617ae80fb23500d21 broke Trap exception handling in the standard MIPS mode. Additionally the microMIPS-mode trap code mask is wrong, as it's a 4-bit field. Here's a fix. Signed-off-by: Maciej W. Rozycki Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/5309/ Signed-off-by: Ralf Baechle --- arch/mips/kernel/traps.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-) diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index e3be67012d78..a75ae40184aa 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -897,22 +897,24 @@ out_sigsegv: asmlinkage void do_tr(struct pt_regs *regs) { - unsigned int opcode, tcode = 0; + u32 opcode, tcode = 0; u16 instr[2]; - unsigned long epc = exception_epc(regs); + unsigned long epc = msk_isa16_mode(exception_epc(regs)); - if ((__get_user(instr[0], (u16 __user *)msk_isa16_mode(epc))) || - (__get_user(instr[1], (u16 __user *)msk_isa16_mode(epc + 2)))) + if (get_isa16_mode(regs->cp0_epc)) { + if (__get_user(instr[0], (u16 __user *)(epc + 0)) || + __get_user(instr[1], (u16 __user *)(epc + 2))) goto out_sigsegv; - opcode = (instr[0] << 16) | instr[1]; - - /* Immediate versions don't provide a code. */ - if (!(opcode & OPCODE)) { - if (get_isa16_mode(regs->cp0_epc)) - /* microMIPS */ - tcode = (opcode >> 12) & 0x1f; - else - tcode = ((opcode >> 6) & ((1 << 10) - 1)); + opcode = (instr[0] << 16) | instr[1]; + /* Immediate versions don't provide a code. */ + if (!(opcode & OPCODE)) + tcode = (opcode >> 12) & ((1 << 4) - 1); + } else { + if (__get_user(opcode, (u32 __user *)epc)) + goto out_sigsegv; + /* Immediate versions don't provide a code. */ + if (!(opcode & OPCODE)) + tcode = (opcode >> 6) & ((1 << 10) - 1); } do_trap_or_bp(regs, tcode, "Trap"); -- 2.34.1