diff options
| author |   Maciej W. Rozycki <macro@imgtec.com> | 2016-01-30 09:08:43 +0000 |
|---|---|---|
| committer |   Ralf Baechle <ralf@linux-mips.org> | 2016-04-04 15:25:34 +0200 |
| commit | 3d50a7fb42992545e45e10b068406546ea699489 (patch) | |
| tree | 377a54dd0c80f3f287e4463d3ea9577866384cfa /arch | |
| parent | MIPS: BMIPS: Fix gisb-arb compatible string for 7435 (diff) | |
| download | linux-dev-3d50a7fb42992545e45e10b068406546ea699489.tar.xz linux-dev-3d50a7fb42992545e45e10b068406546ea699489.zip | |
MIPS: traps.c: Verify the ISA for microMIPS RDHWR emulation
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>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/kernel/traps.c | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 80339ce64521..ae0c89d23ad7 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -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) |