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| author | David A. Long <dave.long@linaro.org> | 2016-07-08 19:35:47 +0300 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2016-07-19 17:03:19 +0300 |
| commit | 2af3ec08b414ceb9c32fad2bb0f87252f3f18de8 (patch) | |
| tree | ff2603ec647205a23d00ae652b994a29f703be28 /arch/arm64/kernel/armv8_deprecated.c | |
| parent | d59bee887231191c80f2ee674d7ec19179eb40ec (diff) | |
| download | linux-2af3ec08b414ceb9c32fad2bb0f87252f3f18de8.tar.xz | |
arm64: add conditional instruction simulation support
Cease using the arm32 arm_check_condition() function and replace it with
a local version for use in deprecated instruction support on arm64. Also
make the function table used by this available for future use by kprobes
and/or uprobes.
This function is derived from code written by Sandeepa Prabhu.
Signed-off-by: Sandeepa Prabhu <sandeepa.s.prabhu@gmail.com>
Signed-off-by: David A. Long <dave.long@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/kernel/armv8_deprecated.c')
| -rw-r--r-- | arch/arm64/kernel/armv8_deprecated.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c index c37202c0c838..293489476529 100644 --- a/arch/arm64/kernel/armv8_deprecated.c +++ b/arch/arm64/kernel/armv8_deprecated.c @@ -366,6 +366,21 @@ static int emulate_swpX(unsigned int address, unsigned int *data, return res; } +#define ARM_OPCODE_CONDITION_UNCOND 0xf + +static unsigned int __kprobes aarch32_check_condition(u32 opcode, u32 psr) +{ + u32 cc_bits = opcode >> 28; + + if (cc_bits != ARM_OPCODE_CONDITION_UNCOND) { + if ((*aarch32_opcode_cond_checks[cc_bits])(psr)) + return ARM_OPCODE_CONDTEST_PASS; + else + return ARM_OPCODE_CONDTEST_FAIL; + } + return ARM_OPCODE_CONDTEST_UNCOND; +} + /* * swp_handler logs the id of calling process, dissects the instruction, sanity * checks the memory location, calls emulate_swpX for the actual operation and @@ -380,7 +395,7 @@ static int swp_handler(struct pt_regs *regs, u32 instr) type = instr & TYPE_SWPB; - switch (arm_check_condition(instr, regs->pstate)) { + switch (aarch32_check_condition(instr, regs->pstate)) { case ARM_OPCODE_CONDTEST_PASS: break; case ARM_OPCODE_CONDTEST_FAIL: @@ -461,7 +476,7 @@ static int cp15barrier_handler(struct pt_regs *regs, u32 instr) { perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, regs->pc); - switch (arm_check_condition(instr, regs->pstate)) { + switch (aarch32_check_condition(instr, regs->pstate)) { case ARM_OPCODE_CONDTEST_PASS: break; case ARM_OPCODE_CONDTEST_FAIL: |