MIPS: kernel: Prepare the JR instruction for emulation on MIPS R6 (5f9f41c4) · Commits · 戴 / test

arch/mips/include/asm/branch.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -13,6 +13,9 @@
		#include <asm/ptrace.h>
		#include <asm/inst.h>

		static int mipsr2_emulation = 0;
		#define NO_R6EMU (cpu_has_mips_r6 && !mipsr2_emulation)

		extern int __isa_exception_epc(struct pt_regs *regs);
		extern int __compute_return_epc(struct pt_regs *regs);
		extern int __compute_return_epc_for_insn(struct pt_regs *regs,

+9 −2

Original line number	Diff line number	Diff line
		@@ -417,6 +417,8 @@ int __compute_return_epc_for_insn(struct pt_regs *regs,
		regs->regs[insn.r_format.rd] = epc + 8;
		/* Fall through */
		case jr_op:
		if (NO_R6EMU && insn.r_format.func == jr_op)
		goto sigill_r6;
		regs->cp0_epc = regs->regs[insn.r_format.rs];
		break;
		}
		@@ -477,7 +479,7 @@ int __compute_return_epc_for_insn(struct pt_regs *regs,

		case bposge32_op:
		if (!cpu_has_dsp)
		goto sigill;
		goto sigill_dsp;

		dspcontrol = rddsp(0x01);

		@@ -631,10 +633,15 @@ int __compute_return_epc_for_insn(struct pt_regs *regs,

		return ret;

		sigill:
		sigill_dsp:
		printk("%s: DSP branch but not DSP ASE - sending SIGBUS.\n", current->comm);
		force_sig(SIGBUS, current);
		return -EFAULT;
		sigill_r6:
		pr_info("%s: R2 branch but r2-to-r6 emulator is not preset - sending SIGILL.\n",
		current->comm);
		force_sig(SIGILL, current);
		return -EFAULT;
		}
		EXPORT_SYMBOL_GPL(__compute_return_epc_for_insn);

+3 −0

Original line number	Diff line number	Diff line
		@@ -448,6 +448,9 @@ static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
		dec_insn.next_pc_inc;
		/* Fall through */
		case jr_op:
		/* For R6, JR already emulated in jalr_op */
		if (NO_R6EMU && insn.r_format.opcode == jr_op)
		break;
		*contpc = regs->regs[insn.r_format.rs];
		return 1;
		}