From c1771216ab48bb077cee30e6d197a5a55f707101 Mon Sep 17 00:00:00 2001 From: Leonid Yegoshin Date: Thu, 12 Dec 2013 16:15:15 +0000 Subject: [PATCH] MIPS: kernel: unaligned: Handle unaligned accesses for EVA Handle unaligned accesses when we access userspace memory EVA mode. Signed-off-by: Leonid Yegoshin Signed-off-by: Markos Chandras --- arch/mips/kernel/unaligned.c | 86 +++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 85 insertions(+), 1 deletion(-) diff --git a/arch/mips/kernel/unaligned.c b/arch/mips/kernel/unaligned.c index 5ec8f00b51b5..2b3517214d6d 100644 --- a/arch/mips/kernel/unaligned.c +++ b/arch/mips/kernel/unaligned.c @@ -431,7 +431,9 @@ static void emulate_load_store_insn(struct pt_regs *regs, unsigned long origpc; unsigned long orig31; void __user *fault_addr = NULL; - +#ifdef CONFIG_EVA + mm_segment_t seg; +#endif origpc = (unsigned long)pc; orig31 = regs->regs[31]; @@ -476,6 +478,88 @@ static void emulate_load_store_insn(struct pt_regs *regs, * The remaining opcodes are the ones that are really of * interest. */ +#ifdef CONFIG_EVA + case spec3_op: + /* + * we can land here only from kernel accessing user memory, + * so we need to "switch" the address limit to user space, so + * address check can work properly. + */ + seg = get_fs(); + set_fs(USER_DS); + switch (insn.spec3_format.func) { + case lhe_op: + if (!access_ok(VERIFY_READ, addr, 2)) { + set_fs(seg); + goto sigbus; + } + LoadHW(addr, value, res); + if (res) { + set_fs(seg); + goto fault; + } + compute_return_epc(regs); + regs->regs[insn.spec3_format.rt] = value; + break; + case lwe_op: + if (!access_ok(VERIFY_READ, addr, 4)) { + set_fs(seg); + goto sigbus; + } + LoadW(addr, value, res); + if (res) { + set_fs(seg); + goto fault; + } + compute_return_epc(regs); + regs->regs[insn.spec3_format.rt] = value; + break; + case lhue_op: + if (!access_ok(VERIFY_READ, addr, 2)) { + set_fs(seg); + goto sigbus; + } + LoadHWU(addr, value, res); + if (res) { + set_fs(seg); + goto fault; + } + compute_return_epc(regs); + regs->regs[insn.spec3_format.rt] = value; + break; + case she_op: + if (!access_ok(VERIFY_WRITE, addr, 2)) { + set_fs(seg); + goto sigbus; + } + compute_return_epc(regs); + value = regs->regs[insn.spec3_format.rt]; + StoreHW(addr, value, res); + if (res) { + set_fs(seg); + goto fault; + } + break; + case swe_op: + if (!access_ok(VERIFY_WRITE, addr, 4)) { + set_fs(seg); + goto sigbus; + } + compute_return_epc(regs); + value = regs->regs[insn.spec3_format.rt]; + StoreW(addr, value, res); + if (res) { + set_fs(seg); + goto fault; + } + break; + default: + set_fs(seg); + goto sigill; + } + set_fs(seg); + break; +#endif case lh_op: if (!access_ok(VERIFY_READ, addr, 2)) goto sigbus; -- 2.11.0