MIPS: traps.c: Verify the ISA for microMIPS RDHWR emulation (3d50a7fb) · Commits · 戴 / test

Make sure it's the microMIPS rather than MIPS16 ISA before emulating microMIPS RDHWR. Mostly needed as an optimisation for configurations where `cpu_has_mmips' is hardcoded to 0 and also a good measure in case we add further microMIPS instructions to emulate in the future, as the corresponding MIPS16 encoding is ADDIUSP, not supposed to trap. Signed-off-by:

Maciej W. Rozycki <macro@imgtec.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/12282/ Signed-off-by:

Ralf Baechle <ralf@linux-mips.org>

arch/mips/kernel/traps.c

+13 −13

Original line number	Diff line number	Diff line
		@@ -1122,19 +1122,7 @@ no_r2_instr:
		if (unlikely(compute_return_epc(regs) < 0))
		goto out;

		if (get_isa16_mode(regs->cp0_epc)) {
		unsigned short mmop[2] = { 0 };

		if (unlikely(get_user(mmop[0], (u16 __user *)epc + 0) < 0))
		status = SIGSEGV;
		if (unlikely(get_user(mmop[1], (u16 __user *)epc + 1) < 0))
		status = SIGSEGV;
		opcode = mmop[0];
		opcode = (opcode << 16) \| mmop[1];

		if (status < 0)
		status = simulate_rdhwr_mm(regs, opcode);
		} else {
		if (!get_isa16_mode(regs->cp0_epc)) {
		if (unlikely(get_user(opcode, epc) < 0))
		status = SIGSEGV;

		@@ -1149,6 +1137,18 @@ no_r2_instr:

		if (status < 0)
		status = simulate_fp(regs, opcode, old_epc, old31);
		} else if (cpu_has_mmips) {
		unsigned short mmop[2] = { 0 };

		if (unlikely(get_user(mmop[0], (u16 __user *)epc + 0) < 0))
		status = SIGSEGV;
		if (unlikely(get_user(mmop[1], (u16 __user *)epc + 1) < 0))
		status = SIGSEGV;
		opcode = mmop[0];
		opcode = (opcode << 16) \| mmop[1];

		if (status < 0)
		status = simulate_rdhwr_mm(regs, opcode);
		}

		if (status < 0)

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