From 7aa7047100113ec9f5e4e685f94223825bd74a7b Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Sat, 30 Jan 2016 09:08:28 +0000 Subject: MIPS: traps.c: Correct microMIPS RDHWR emulation Fix the code to fetch and decode the whole 32-bit instruction. This only really matters with the `noulri' kernel parameter as all microMIPS processors are supposed to have all the hardware registers we support. Signed-off-by: Maciej W. Rozycki Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12281/ Signed-off-by: Ralf Baechle --- arch/mips/kernel/traps.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 485b0d517177..ae790c575d4f 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -663,7 +663,7 @@ static int simulate_rdhwr_normal(struct pt_regs *regs, unsigned int opcode) return -1; } -static int simulate_rdhwr_mm(struct pt_regs *regs, unsigned short opcode) +static int simulate_rdhwr_mm(struct pt_regs *regs, unsigned int opcode) { if ((opcode & MM_POOL32A_FUNC) == MM_RDHWR) { int rd = (opcode & MM_RS) >> 16; @@ -1119,11 +1119,12 @@ no_r2_instr: if (get_isa16_mode(regs->cp0_epc)) { unsigned short mmop[2] = { 0 }; - if (unlikely(get_user(mmop[0], epc) < 0)) + if (unlikely(get_user(mmop[0], (u16 __user *)epc + 0) < 0)) status = SIGSEGV; - if (unlikely(get_user(mmop[1], epc) < 0)) + if (unlikely(get_user(mmop[1], (u16 __user *)epc + 1) < 0)) status = SIGSEGV; - opcode = (mmop[0] << 16) | mmop[1]; + opcode = mmop[0]; + opcode = (opcode << 16) | mmop[1]; if (status < 0) status = simulate_rdhwr_mm(regs, opcode); -- cgit v1.2.3-59-g8ed1b