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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/arm/probes/decode-arm.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/probes/decode-arm.c')
-rw-r--r--arch/arm/probes/decode-arm.c736
1 files changed, 736 insertions, 0 deletions
diff --git a/arch/arm/probes/decode-arm.c b/arch/arm/probes/decode-arm.c
new file mode 100644
index 000000000..f72c33a2d
--- /dev/null
+++ b/arch/arm/probes/decode-arm.c
@@ -0,0 +1,736 @@
+/*
+ *
+ * arch/arm/probes/decode-arm.c
+ *
+ * Some code moved here from arch/arm/kernel/kprobes-arm.c
+ *
+ * Copyright (C) 2006, 2007 Motorola Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/stddef.h>
+#include <linux/ptrace.h>
+
+#include "decode.h"
+#include "decode-arm.h"
+
+#define sign_extend(x, signbit) ((x) | (0 - ((x) & (1 << (signbit)))))
+
+#define branch_displacement(insn) sign_extend(((insn) & 0xffffff) << 2, 25)
+
+/*
+ * To avoid the complications of mimicing single-stepping on a
+ * processor without a Next-PC or a single-step mode, and to
+ * avoid having to deal with the side-effects of boosting, we
+ * simulate or emulate (almost) all ARM instructions.
+ *
+ * "Simulation" is where the instruction's behavior is duplicated in
+ * C code. "Emulation" is where the original instruction is rewritten
+ * and executed, often by altering its registers.
+ *
+ * By having all behavior of the kprobe'd instruction completed before
+ * returning from the kprobe_handler(), all locks (scheduler and
+ * interrupt) can safely be released. There is no need for secondary
+ * breakpoints, no race with MP or preemptable kernels, nor having to
+ * clean up resources counts at a later time impacting overall system
+ * performance. By rewriting the instruction, only the minimum registers
+ * need to be loaded and saved back optimizing performance.
+ *
+ * Calling the insnslot_*_rwflags version of a function doesn't hurt
+ * anything even when the CPSR flags aren't updated by the
+ * instruction. It's just a little slower in return for saving
+ * a little space by not having a duplicate function that doesn't
+ * update the flags. (The same optimization can be said for
+ * instructions that do or don't perform register writeback)
+ * Also, instructions can either read the flags, only write the
+ * flags, or read and write the flags. To save combinations
+ * rather than for sheer performance, flag functions just assume
+ * read and write of flags.
+ */
+
+void __kprobes simulate_bbl(probes_opcode_t insn,
+ struct arch_probes_insn *asi, struct pt_regs *regs)
+{
+ long iaddr = (long) regs->ARM_pc - 4;
+ int disp = branch_displacement(insn);
+
+ if (insn & (1 << 24))
+ regs->ARM_lr = iaddr + 4;
+
+ regs->ARM_pc = iaddr + 8 + disp;
+}
+
+void __kprobes simulate_blx1(probes_opcode_t insn,
+ struct arch_probes_insn *asi, struct pt_regs *regs)
+{
+ long iaddr = (long) regs->ARM_pc - 4;
+ int disp = branch_displacement(insn);
+
+ regs->ARM_lr = iaddr + 4;
+ regs->ARM_pc = iaddr + 8 + disp + ((insn >> 23) & 0x2);
+ regs->ARM_cpsr |= PSR_T_BIT;
+}
+
+void __kprobes simulate_blx2bx(probes_opcode_t insn,
+ struct arch_probes_insn *asi, struct pt_regs *regs)
+{
+ int rm = insn & 0xf;
+ long rmv = regs->uregs[rm];
+
+ if (insn & (1 << 5))
+ regs->ARM_lr = (long) regs->ARM_pc;
+
+ regs->ARM_pc = rmv & ~0x1;
+ regs->ARM_cpsr &= ~PSR_T_BIT;
+ if (rmv & 0x1)
+ regs->ARM_cpsr |= PSR_T_BIT;
+}
+
+void __kprobes simulate_mrs(probes_opcode_t insn,
+ struct arch_probes_insn *asi, struct pt_regs *regs)
+{
+ int rd = (insn >> 12) & 0xf;
+ unsigned long mask = 0xf8ff03df; /* Mask out execution state */
+ regs->uregs[rd] = regs->ARM_cpsr & mask;
+}
+
+void __kprobes simulate_mov_ipsp(probes_opcode_t insn,
+ struct arch_probes_insn *asi, struct pt_regs *regs)
+{
+ regs->uregs[12] = regs->uregs[13];
+}
+
+/*
+ * For the instruction masking and comparisons in all the "space_*"
+ * functions below, Do _not_ rearrange the order of tests unless
+ * you're very, very sure of what you are doing. For the sake of
+ * efficiency, the masks for some tests sometimes assume other test
+ * have been done prior to them so the number of patterns to test
+ * for an instruction set can be as broad as possible to reduce the
+ * number of tests needed.
+ */
+
+static const union decode_item arm_1111_table[] = {
+ /* Unconditional instructions */
+
+ /* memory hint 1111 0100 x001 xxxx xxxx xxxx xxxx xxxx */
+ /* PLDI (immediate) 1111 0100 x101 xxxx xxxx xxxx xxxx xxxx */
+ /* PLDW (immediate) 1111 0101 x001 xxxx xxxx xxxx xxxx xxxx */
+ /* PLD (immediate) 1111 0101 x101 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_SIMULATE (0xfe300000, 0xf4100000, PROBES_PRELOAD_IMM),
+
+ /* memory hint 1111 0110 x001 xxxx xxxx xxxx xxx0 xxxx */
+ /* PLDI (register) 1111 0110 x101 xxxx xxxx xxxx xxx0 xxxx */
+ /* PLDW (register) 1111 0111 x001 xxxx xxxx xxxx xxx0 xxxx */
+ /* PLD (register) 1111 0111 x101 xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_SIMULATE (0xfe300010, 0xf6100000, PROBES_PRELOAD_REG),
+
+ /* BLX (immediate) 1111 101x xxxx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_SIMULATE (0xfe000000, 0xfa000000, PROBES_BRANCH_IMM),
+
+ /* CPS 1111 0001 0000 xxx0 xxxx xxxx xx0x xxxx */
+ /* SETEND 1111 0001 0000 0001 xxxx xxxx 0000 xxxx */
+ /* SRS 1111 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ /* RFE 1111 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
+
+ /* Coprocessor instructions... */
+ /* MCRR2 1111 1100 0100 xxxx xxxx xxxx xxxx xxxx */
+ /* MRRC2 1111 1100 0101 xxxx xxxx xxxx xxxx xxxx */
+ /* LDC2 1111 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
+ /* STC2 1111 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
+ /* CDP2 1111 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
+ /* MCR2 1111 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
+ /* MRC2 1111 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
+
+ /* Other unallocated instructions... */
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_0xx0____0xxx_table[] = {
+ /* Miscellaneous instructions */
+
+ /* MRS cpsr cccc 0001 0000 xxxx xxxx xxxx 0000 xxxx */
+ DECODE_SIMULATEX(0x0ff000f0, 0x01000000, PROBES_MRS,
+ REGS(0, NOPC, 0, 0, 0)),
+
+ /* BX cccc 0001 0010 xxxx xxxx xxxx 0001 xxxx */
+ DECODE_SIMULATE (0x0ff000f0, 0x01200010, PROBES_BRANCH_REG),
+
+ /* BLX (register) cccc 0001 0010 xxxx xxxx xxxx 0011 xxxx */
+ DECODE_SIMULATEX(0x0ff000f0, 0x01200030, PROBES_BRANCH_REG,
+ REGS(0, 0, 0, 0, NOPC)),
+
+ /* CLZ cccc 0001 0110 xxxx xxxx xxxx 0001 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x01600010, PROBES_CLZ,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* QADD cccc 0001 0000 xxxx xxxx xxxx 0101 xxxx */
+ /* QSUB cccc 0001 0010 xxxx xxxx xxxx 0101 xxxx */
+ /* QDADD cccc 0001 0100 xxxx xxxx xxxx 0101 xxxx */
+ /* QDSUB cccc 0001 0110 xxxx xxxx xxxx 0101 xxxx */
+ DECODE_EMULATEX (0x0f9000f0, 0x01000050, PROBES_SATURATING_ARITHMETIC,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* BXJ cccc 0001 0010 xxxx xxxx xxxx 0010 xxxx */
+ /* MSR cccc 0001 0x10 xxxx xxxx xxxx 0000 xxxx */
+ /* MRS spsr cccc 0001 0100 xxxx xxxx xxxx 0000 xxxx */
+ /* BKPT 1110 0001 0010 xxxx xxxx xxxx 0111 xxxx */
+ /* SMC cccc 0001 0110 xxxx xxxx xxxx 0111 xxxx */
+ /* And unallocated instructions... */
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_0xx0____1xx0_table[] = {
+ /* Halfword multiply and multiply-accumulate */
+
+ /* SMLALxy cccc 0001 0100 xxxx xxxx xxxx 1xx0 xxxx */
+ DECODE_EMULATEX (0x0ff00090, 0x01400080, PROBES_MUL1,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* SMULWy cccc 0001 0010 xxxx xxxx xxxx 1x10 xxxx */
+ DECODE_OR (0x0ff000b0, 0x012000a0),
+ /* SMULxy cccc 0001 0110 xxxx xxxx xxxx 1xx0 xxxx */
+ DECODE_EMULATEX (0x0ff00090, 0x01600080, PROBES_MUL2,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* SMLAxy cccc 0001 0000 xxxx xxxx xxxx 1xx0 xxxx */
+ DECODE_OR (0x0ff00090, 0x01000080),
+ /* SMLAWy cccc 0001 0010 xxxx xxxx xxxx 1x00 xxxx */
+ DECODE_EMULATEX (0x0ff000b0, 0x01200080, PROBES_MUL2,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0000_____1001_table[] = {
+ /* Multiply and multiply-accumulate */
+
+ /* MUL cccc 0000 0000 xxxx xxxx xxxx 1001 xxxx */
+ /* MULS cccc 0000 0001 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0fe000f0, 0x00000090, PROBES_MUL2,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* MLA cccc 0000 0010 xxxx xxxx xxxx 1001 xxxx */
+ /* MLAS cccc 0000 0011 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_OR (0x0fe000f0, 0x00200090),
+ /* MLS cccc 0000 0110 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x00600090, PROBES_MUL2,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* UMAAL cccc 0000 0100 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_OR (0x0ff000f0, 0x00400090),
+ /* UMULL cccc 0000 1000 xxxx xxxx xxxx 1001 xxxx */
+ /* UMULLS cccc 0000 1001 xxxx xxxx xxxx 1001 xxxx */
+ /* UMLAL cccc 0000 1010 xxxx xxxx xxxx 1001 xxxx */
+ /* UMLALS cccc 0000 1011 xxxx xxxx xxxx 1001 xxxx */
+ /* SMULL cccc 0000 1100 xxxx xxxx xxxx 1001 xxxx */
+ /* SMULLS cccc 0000 1101 xxxx xxxx xxxx 1001 xxxx */
+ /* SMLAL cccc 0000 1110 xxxx xxxx xxxx 1001 xxxx */
+ /* SMLALS cccc 0000 1111 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0f8000f0, 0x00800090, PROBES_MUL1,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0001_____1001_table[] = {
+ /* Synchronization primitives */
+
+#if __LINUX_ARM_ARCH__ < 6
+ /* Deprecated on ARMv6 and may be UNDEFINED on v7 */
+ /* SMP/SWPB cccc 0001 0x00 xxxx xxxx xxxx 1001 xxxx */
+ DECODE_EMULATEX (0x0fb000f0, 0x01000090, PROBES_SWP,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+#endif
+ /* LDREX/STREX{,D,B,H} cccc 0001 1xxx xxxx xxxx xxxx 1001 xxxx */
+ /* And unallocated instructions... */
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_000x_____1xx1_table[] = {
+ /* Extra load/store instructions */
+
+ /* STRHT cccc 0000 xx10 xxxx xxxx xxxx 1011 xxxx */
+ /* ??? cccc 0000 xx10 xxxx xxxx xxxx 11x1 xxxx */
+ /* LDRHT cccc 0000 xx11 xxxx xxxx xxxx 1011 xxxx */
+ /* LDRSBT cccc 0000 xx11 xxxx xxxx xxxx 1101 xxxx */
+ /* LDRSHT cccc 0000 xx11 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_REJECT (0x0f200090, 0x00200090),
+
+ /* LDRD/STRD lr,pc,{... cccc 000x x0x0 xxxx 111x xxxx 1101 xxxx */
+ DECODE_REJECT (0x0e10e0d0, 0x0000e0d0),
+
+ /* LDRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1101 xxxx */
+ /* STRD (register) cccc 000x x0x0 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e5000d0, 0x000000d0, PROBES_LDRSTRD,
+ REGS(NOPCWB, NOPCX, 0, 0, NOPC)),
+
+ /* LDRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1101 xxxx */
+ /* STRD (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e5000d0, 0x004000d0, PROBES_LDRSTRD,
+ REGS(NOPCWB, NOPCX, 0, 0, 0)),
+
+ /* STRH (register) cccc 000x x0x0 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0e5000f0, 0x000000b0, PROBES_STORE_EXTRA,
+ REGS(NOPCWB, NOPC, 0, 0, NOPC)),
+
+ /* LDRH (register) cccc 000x x0x1 xxxx xxxx xxxx 1011 xxxx */
+ /* LDRSB (register) cccc 000x x0x1 xxxx xxxx xxxx 1101 xxxx */
+ /* LDRSH (register) cccc 000x x0x1 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e500090, 0x00100090, PROBES_LOAD_EXTRA,
+ REGS(NOPCWB, NOPC, 0, 0, NOPC)),
+
+ /* STRH (immediate) cccc 000x x1x0 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0e5000f0, 0x004000b0, PROBES_STORE_EXTRA,
+ REGS(NOPCWB, NOPC, 0, 0, 0)),
+
+ /* LDRH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1011 xxxx */
+ /* LDRSB (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1101 xxxx */
+ /* LDRSH (immediate) cccc 000x x1x1 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0e500090, 0x00500090, PROBES_LOAD_EXTRA,
+ REGS(NOPCWB, NOPC, 0, 0, 0)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_000x_table[] = {
+ /* Data-processing (register) */
+
+ /* <op>S PC, ... cccc 000x xxx1 xxxx 1111 xxxx xxxx xxxx */
+ DECODE_REJECT (0x0e10f000, 0x0010f000),
+
+ /* MOV IP, SP 1110 0001 1010 0000 1100 0000 0000 1101 */
+ DECODE_SIMULATE (0xffffffff, 0xe1a0c00d, PROBES_MOV_IP_SP),
+
+ /* TST (register) cccc 0001 0001 xxxx xxxx xxxx xxx0 xxxx */
+ /* TEQ (register) cccc 0001 0011 xxxx xxxx xxxx xxx0 xxxx */
+ /* CMP (register) cccc 0001 0101 xxxx xxxx xxxx xxx0 xxxx */
+ /* CMN (register) cccc 0001 0111 xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_EMULATEX (0x0f900010, 0x01100000, PROBES_DATA_PROCESSING_REG,
+ REGS(ANY, 0, 0, 0, ANY)),
+
+ /* MOV (register) cccc 0001 101x xxxx xxxx xxxx xxx0 xxxx */
+ /* MVN (register) cccc 0001 111x xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_EMULATEX (0x0fa00010, 0x01a00000, PROBES_DATA_PROCESSING_REG,
+ REGS(0, ANY, 0, 0, ANY)),
+
+ /* AND (register) cccc 0000 000x xxxx xxxx xxxx xxx0 xxxx */
+ /* EOR (register) cccc 0000 001x xxxx xxxx xxxx xxx0 xxxx */
+ /* SUB (register) cccc 0000 010x xxxx xxxx xxxx xxx0 xxxx */
+ /* RSB (register) cccc 0000 011x xxxx xxxx xxxx xxx0 xxxx */
+ /* ADD (register) cccc 0000 100x xxxx xxxx xxxx xxx0 xxxx */
+ /* ADC (register) cccc 0000 101x xxxx xxxx xxxx xxx0 xxxx */
+ /* SBC (register) cccc 0000 110x xxxx xxxx xxxx xxx0 xxxx */
+ /* RSC (register) cccc 0000 111x xxxx xxxx xxxx xxx0 xxxx */
+ /* ORR (register) cccc 0001 100x xxxx xxxx xxxx xxx0 xxxx */
+ /* BIC (register) cccc 0001 110x xxxx xxxx xxxx xxx0 xxxx */
+ DECODE_EMULATEX (0x0e000010, 0x00000000, PROBES_DATA_PROCESSING_REG,
+ REGS(ANY, ANY, 0, 0, ANY)),
+
+ /* TST (reg-shift reg) cccc 0001 0001 xxxx xxxx xxxx 0xx1 xxxx */
+ /* TEQ (reg-shift reg) cccc 0001 0011 xxxx xxxx xxxx 0xx1 xxxx */
+ /* CMP (reg-shift reg) cccc 0001 0101 xxxx xxxx xxxx 0xx1 xxxx */
+ /* CMN (reg-shift reg) cccc 0001 0111 xxxx xxxx xxxx 0xx1 xxxx */
+ DECODE_EMULATEX (0x0f900090, 0x01100010, PROBES_DATA_PROCESSING_REG,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* MOV (reg-shift reg) cccc 0001 101x xxxx xxxx xxxx 0xx1 xxxx */
+ /* MVN (reg-shift reg) cccc 0001 111x xxxx xxxx xxxx 0xx1 xxxx */
+ DECODE_EMULATEX (0x0fa00090, 0x01a00010, PROBES_DATA_PROCESSING_REG,
+ REGS(0, NOPC, NOPC, 0, NOPC)),
+
+ /* AND (reg-shift reg) cccc 0000 000x xxxx xxxx xxxx 0xx1 xxxx */
+ /* EOR (reg-shift reg) cccc 0000 001x xxxx xxxx xxxx 0xx1 xxxx */
+ /* SUB (reg-shift reg) cccc 0000 010x xxxx xxxx xxxx 0xx1 xxxx */
+ /* RSB (reg-shift reg) cccc 0000 011x xxxx xxxx xxxx 0xx1 xxxx */
+ /* ADD (reg-shift reg) cccc 0000 100x xxxx xxxx xxxx 0xx1 xxxx */
+ /* ADC (reg-shift reg) cccc 0000 101x xxxx xxxx xxxx 0xx1 xxxx */
+ /* SBC (reg-shift reg) cccc 0000 110x xxxx xxxx xxxx 0xx1 xxxx */
+ /* RSC (reg-shift reg) cccc 0000 111x xxxx xxxx xxxx 0xx1 xxxx */
+ /* ORR (reg-shift reg) cccc 0001 100x xxxx xxxx xxxx 0xx1 xxxx */
+ /* BIC (reg-shift reg) cccc 0001 110x xxxx xxxx xxxx 0xx1 xxxx */
+ DECODE_EMULATEX (0x0e000090, 0x00000010, PROBES_DATA_PROCESSING_REG,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_001x_table[] = {
+ /* Data-processing (immediate) */
+
+ /* MOVW cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
+ /* MOVT cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0fb00000, 0x03000000, PROBES_MOV_HALFWORD,
+ REGS(0, NOPC, 0, 0, 0)),
+
+ /* YIELD cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
+ DECODE_OR (0x0fff00ff, 0x03200001),
+ /* SEV cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
+ DECODE_EMULATE (0x0fff00ff, 0x03200004, PROBES_SEV),
+ /* NOP cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
+ /* WFE cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
+ /* WFI cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
+ DECODE_SIMULATE (0x0fff00fc, 0x03200000, PROBES_WFE),
+ /* DBG cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
+ /* unallocated hints cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
+ /* MSR (immediate) cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0fb00000, 0x03200000),
+
+ /* <op>S PC, ... cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
+ DECODE_REJECT (0x0e10f000, 0x0210f000),
+
+ /* TST (immediate) cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
+ /* TEQ (immediate) cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
+ /* CMP (immediate) cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
+ /* CMN (immediate) cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0f900000, 0x03100000, PROBES_DATA_PROCESSING_IMM,
+ REGS(ANY, 0, 0, 0, 0)),
+
+ /* MOV (immediate) cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
+ /* MVN (immediate) cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0fa00000, 0x03a00000, PROBES_DATA_PROCESSING_IMM,
+ REGS(0, ANY, 0, 0, 0)),
+
+ /* AND (immediate) cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
+ /* EOR (immediate) cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
+ /* SUB (immediate) cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
+ /* RSB (immediate) cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
+ /* ADD (immediate) cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
+ /* ADC (immediate) cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
+ /* SBC (immediate) cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
+ /* RSC (immediate) cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
+ /* ORR (immediate) cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
+ /* BIC (immediate) cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e000000, 0x02000000, PROBES_DATA_PROCESSING_IMM,
+ REGS(ANY, ANY, 0, 0, 0)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0110_____xxx1_table[] = {
+ /* Media instructions */
+
+ /* SEL cccc 0110 1000 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x068000b0, PROBES_SATURATE,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* SSAT cccc 0110 101x xxxx xxxx xxxx xx01 xxxx */
+ /* USAT cccc 0110 111x xxxx xxxx xxxx xx01 xxxx */
+ DECODE_OR(0x0fa00030, 0x06a00010),
+ /* SSAT16 cccc 0110 1010 xxxx xxxx xxxx 0011 xxxx */
+ /* USAT16 cccc 0110 1110 xxxx xxxx xxxx 0011 xxxx */
+ DECODE_EMULATEX (0x0fb000f0, 0x06a00030, PROBES_SATURATE,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* REV cccc 0110 1011 xxxx xxxx xxxx 0011 xxxx */
+ /* REV16 cccc 0110 1011 xxxx xxxx xxxx 1011 xxxx */
+ /* RBIT cccc 0110 1111 xxxx xxxx xxxx 0011 xxxx */
+ /* REVSH cccc 0110 1111 xxxx xxxx xxxx 1011 xxxx */
+ DECODE_EMULATEX (0x0fb00070, 0x06b00030, PROBES_REV,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* ??? cccc 0110 0x00 xxxx xxxx xxxx xxx1 xxxx */
+ DECODE_REJECT (0x0fb00010, 0x06000010),
+ /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1011 xxxx */
+ DECODE_REJECT (0x0f8000f0, 0x060000b0),
+ /* ??? cccc 0110 0xxx xxxx xxxx xxxx 1101 xxxx */
+ DECODE_REJECT (0x0f8000f0, 0x060000d0),
+ /* SADD16 cccc 0110 0001 xxxx xxxx xxxx 0001 xxxx */
+ /* SADDSUBX cccc 0110 0001 xxxx xxxx xxxx 0011 xxxx */
+ /* SSUBADDX cccc 0110 0001 xxxx xxxx xxxx 0101 xxxx */
+ /* SSUB16 cccc 0110 0001 xxxx xxxx xxxx 0111 xxxx */
+ /* SADD8 cccc 0110 0001 xxxx xxxx xxxx 1001 xxxx */
+ /* SSUB8 cccc 0110 0001 xxxx xxxx xxxx 1111 xxxx */
+ /* QADD16 cccc 0110 0010 xxxx xxxx xxxx 0001 xxxx */
+ /* QADDSUBX cccc 0110 0010 xxxx xxxx xxxx 0011 xxxx */
+ /* QSUBADDX cccc 0110 0010 xxxx xxxx xxxx 0101 xxxx */
+ /* QSUB16 cccc 0110 0010 xxxx xxxx xxxx 0111 xxxx */
+ /* QADD8 cccc 0110 0010 xxxx xxxx xxxx 1001 xxxx */
+ /* QSUB8 cccc 0110 0010 xxxx xxxx xxxx 1111 xxxx */
+ /* SHADD16 cccc 0110 0011 xxxx xxxx xxxx 0001 xxxx */
+ /* SHADDSUBX cccc 0110 0011 xxxx xxxx xxxx 0011 xxxx */
+ /* SHSUBADDX cccc 0110 0011 xxxx xxxx xxxx 0101 xxxx */
+ /* SHSUB16 cccc 0110 0011 xxxx xxxx xxxx 0111 xxxx */
+ /* SHADD8 cccc 0110 0011 xxxx xxxx xxxx 1001 xxxx */
+ /* SHSUB8 cccc 0110 0011 xxxx xxxx xxxx 1111 xxxx */
+ /* UADD16 cccc 0110 0101 xxxx xxxx xxxx 0001 xxxx */
+ /* UADDSUBX cccc 0110 0101 xxxx xxxx xxxx 0011 xxxx */
+ /* USUBADDX cccc 0110 0101 xxxx xxxx xxxx 0101 xxxx */
+ /* USUB16 cccc 0110 0101 xxxx xxxx xxxx 0111 xxxx */
+ /* UADD8 cccc 0110 0101 xxxx xxxx xxxx 1001 xxxx */
+ /* USUB8 cccc 0110 0101 xxxx xxxx xxxx 1111 xxxx */
+ /* UQADD16 cccc 0110 0110 xxxx xxxx xxxx 0001 xxxx */
+ /* UQADDSUBX cccc 0110 0110 xxxx xxxx xxxx 0011 xxxx */
+ /* UQSUBADDX cccc 0110 0110 xxxx xxxx xxxx 0101 xxxx */
+ /* UQSUB16 cccc 0110 0110 xxxx xxxx xxxx 0111 xxxx */
+ /* UQADD8 cccc 0110 0110 xxxx xxxx xxxx 1001 xxxx */
+ /* UQSUB8 cccc 0110 0110 xxxx xxxx xxxx 1111 xxxx */
+ /* UHADD16 cccc 0110 0111 xxxx xxxx xxxx 0001 xxxx */
+ /* UHADDSUBX cccc 0110 0111 xxxx xxxx xxxx 0011 xxxx */
+ /* UHSUBADDX cccc 0110 0111 xxxx xxxx xxxx 0101 xxxx */
+ /* UHSUB16 cccc 0110 0111 xxxx xxxx xxxx 0111 xxxx */
+ /* UHADD8 cccc 0110 0111 xxxx xxxx xxxx 1001 xxxx */
+ /* UHSUB8 cccc 0110 0111 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_EMULATEX (0x0f800010, 0x06000010, PROBES_MMI,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* PKHBT cccc 0110 1000 xxxx xxxx xxxx x001 xxxx */
+ /* PKHTB cccc 0110 1000 xxxx xxxx xxxx x101 xxxx */
+ DECODE_EMULATEX (0x0ff00030, 0x06800010, PROBES_PACK,
+ REGS(NOPC, NOPC, 0, 0, NOPC)),
+
+ /* ??? cccc 0110 1001 xxxx xxxx xxxx 0111 xxxx */
+ /* ??? cccc 0110 1101 xxxx xxxx xxxx 0111 xxxx */
+ DECODE_REJECT (0x0fb000f0, 0x06900070),
+
+ /* SXTB16 cccc 0110 1000 1111 xxxx xxxx 0111 xxxx */
+ /* SXTB cccc 0110 1010 1111 xxxx xxxx 0111 xxxx */
+ /* SXTH cccc 0110 1011 1111 xxxx xxxx 0111 xxxx */
+ /* UXTB16 cccc 0110 1100 1111 xxxx xxxx 0111 xxxx */
+ /* UXTB cccc 0110 1110 1111 xxxx xxxx 0111 xxxx */
+ /* UXTH cccc 0110 1111 1111 xxxx xxxx 0111 xxxx */
+ DECODE_EMULATEX (0x0f8f00f0, 0x068f0070, PROBES_EXTEND,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* SXTAB16 cccc 0110 1000 xxxx xxxx xxxx 0111 xxxx */
+ /* SXTAB cccc 0110 1010 xxxx xxxx xxxx 0111 xxxx */
+ /* SXTAH cccc 0110 1011 xxxx xxxx xxxx 0111 xxxx */
+ /* UXTAB16 cccc 0110 1100 xxxx xxxx xxxx 0111 xxxx */
+ /* UXTAB cccc 0110 1110 xxxx xxxx xxxx 0111 xxxx */
+ /* UXTAH cccc 0110 1111 xxxx xxxx xxxx 0111 xxxx */
+ DECODE_EMULATEX (0x0f8000f0, 0x06800070, PROBES_EXTEND_ADD,
+ REGS(NOPCX, NOPC, 0, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_0111_____xxx1_table[] = {
+ /* Media instructions */
+
+ /* UNDEFINED cccc 0111 1111 xxxx xxxx xxxx 1111 xxxx */
+ DECODE_REJECT (0x0ff000f0, 0x07f000f0),
+
+ /* SMLALD cccc 0111 0100 xxxx xxxx xxxx 00x1 xxxx */
+ /* SMLSLD cccc 0111 0100 xxxx xxxx xxxx 01x1 xxxx */
+ DECODE_EMULATEX (0x0ff00090, 0x07400010, PROBES_MUL_ADD_LONG,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* SMUAD cccc 0111 0000 xxxx 1111 xxxx 00x1 xxxx */
+ /* SMUSD cccc 0111 0000 xxxx 1111 xxxx 01x1 xxxx */
+ DECODE_OR (0x0ff0f090, 0x0700f010),
+ /* SMMUL cccc 0111 0101 xxxx 1111 xxxx 00x1 xxxx */
+ DECODE_OR (0x0ff0f0d0, 0x0750f010),
+ /* USAD8 cccc 0111 1000 xxxx 1111 xxxx 0001 xxxx */
+ DECODE_EMULATEX (0x0ff0f0f0, 0x0780f010, PROBES_MUL_ADD,
+ REGS(NOPC, 0, NOPC, 0, NOPC)),
+
+ /* SMLAD cccc 0111 0000 xxxx xxxx xxxx 00x1 xxxx */
+ /* SMLSD cccc 0111 0000 xxxx xxxx xxxx 01x1 xxxx */
+ DECODE_OR (0x0ff00090, 0x07000010),
+ /* SMMLA cccc 0111 0101 xxxx xxxx xxxx 00x1 xxxx */
+ DECODE_OR (0x0ff000d0, 0x07500010),
+ /* USADA8 cccc 0111 1000 xxxx xxxx xxxx 0001 xxxx */
+ DECODE_EMULATEX (0x0ff000f0, 0x07800010, PROBES_MUL_ADD,
+ REGS(NOPC, NOPCX, NOPC, 0, NOPC)),
+
+ /* SMMLS cccc 0111 0101 xxxx xxxx xxxx 11x1 xxxx */
+ DECODE_EMULATEX (0x0ff000d0, 0x075000d0, PROBES_MUL_ADD,
+ REGS(NOPC, NOPC, NOPC, 0, NOPC)),
+
+ /* SBFX cccc 0111 101x xxxx xxxx xxxx x101 xxxx */
+ /* UBFX cccc 0111 111x xxxx xxxx xxxx x101 xxxx */
+ DECODE_EMULATEX (0x0fa00070, 0x07a00050, PROBES_BITFIELD,
+ REGS(0, NOPC, 0, 0, NOPC)),
+
+ /* BFC cccc 0111 110x xxxx xxxx xxxx x001 1111 */
+ DECODE_EMULATEX (0x0fe0007f, 0x07c0001f, PROBES_BITFIELD,
+ REGS(0, NOPC, 0, 0, 0)),
+
+ /* BFI cccc 0111 110x xxxx xxxx xxxx x001 xxxx */
+ DECODE_EMULATEX (0x0fe00070, 0x07c00010, PROBES_BITFIELD,
+ REGS(0, NOPC, 0, 0, NOPCX)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_01xx_table[] = {
+ /* Load/store word and unsigned byte */
+
+ /* LDRB/STRB pc,[...] cccc 01xx x0xx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0c40f000, 0x0440f000),
+
+ /* STRT cccc 01x0 x010 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRT cccc 01x0 x011 xxxx xxxx xxxx xxxx xxxx */
+ /* STRBT cccc 01x0 x110 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRBT cccc 01x0 x111 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0d200000, 0x04200000),
+
+ /* STR (immediate) cccc 010x x0x0 xxxx xxxx xxxx xxxx xxxx */
+ /* STRB (immediate) cccc 010x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x04000000, PROBES_STORE,
+ REGS(NOPCWB, ANY, 0, 0, 0)),
+
+ /* LDR (immediate) cccc 010x x0x1 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRB (immediate) cccc 010x x1x1 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x04100000, PROBES_LOAD,
+ REGS(NOPCWB, ANY, 0, 0, 0)),
+
+ /* STR (register) cccc 011x x0x0 xxxx xxxx xxxx xxxx xxxx */
+ /* STRB (register) cccc 011x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x06000000, PROBES_STORE,
+ REGS(NOPCWB, ANY, 0, 0, NOPC)),
+
+ /* LDR (register) cccc 011x x0x1 xxxx xxxx xxxx xxxx xxxx */
+ /* LDRB (register) cccc 011x x1x1 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_EMULATEX (0x0e100000, 0x06100000, PROBES_LOAD,
+ REGS(NOPCWB, ANY, 0, 0, NOPC)),
+
+ DECODE_END
+};
+
+static const union decode_item arm_cccc_100x_table[] = {
+ /* Block data transfer instructions */
+
+ /* LDM cccc 100x x0x1 xxxx xxxx xxxx xxxx xxxx */
+ /* STM cccc 100x x0x0 xxxx xxxx xxxx xxxx xxxx */
+ DECODE_CUSTOM (0x0e400000, 0x08000000, PROBES_LDMSTM),
+
+ /* STM (user registers) cccc 100x x1x0 xxxx xxxx xxxx xxxx xxxx */
+ /* LDM (user registers) cccc 100x x1x1 xxxx 0xxx xxxx xxxx xxxx */
+ /* LDM (exception ret) cccc 100x x1x1 xxxx 1xxx xxxx xxxx xxxx */
+ DECODE_END
+};
+
+const union decode_item probes_decode_arm_table[] = {
+ /*
+ * Unconditional instructions
+ * 1111 xxxx xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0xf0000000, 0xf0000000, arm_1111_table),
+
+ /*
+ * Miscellaneous instructions
+ * cccc 0001 0xx0 xxxx xxxx xxxx 0xxx xxxx
+ */
+ DECODE_TABLE (0x0f900080, 0x01000000, arm_cccc_0001_0xx0____0xxx_table),
+
+ /*
+ * Halfword multiply and multiply-accumulate
+ * cccc 0001 0xx0 xxxx xxxx xxxx 1xx0 xxxx
+ */
+ DECODE_TABLE (0x0f900090, 0x01000080, arm_cccc_0001_0xx0____1xx0_table),
+
+ /*
+ * Multiply and multiply-accumulate
+ * cccc 0000 xxxx xxxx xxxx xxxx 1001 xxxx
+ */
+ DECODE_TABLE (0x0f0000f0, 0x00000090, arm_cccc_0000_____1001_table),
+
+ /*
+ * Synchronization primitives
+ * cccc 0001 xxxx xxxx xxxx xxxx 1001 xxxx
+ */
+ DECODE_TABLE (0x0f0000f0, 0x01000090, arm_cccc_0001_____1001_table),
+
+ /*
+ * Extra load/store instructions
+ * cccc 000x xxxx xxxx xxxx xxxx 1xx1 xxxx
+ */
+ DECODE_TABLE (0x0e000090, 0x00000090, arm_cccc_000x_____1xx1_table),
+
+ /*
+ * Data-processing (register)
+ * cccc 000x xxxx xxxx xxxx xxxx xxx0 xxxx
+ * Data-processing (register-shifted register)
+ * cccc 000x xxxx xxxx xxxx xxxx 0xx1 xxxx
+ */
+ DECODE_TABLE (0x0e000000, 0x00000000, arm_cccc_000x_table),
+
+ /*
+ * Data-processing (immediate)
+ * cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0x0e000000, 0x02000000, arm_cccc_001x_table),
+
+ /*
+ * Media instructions
+ * cccc 011x xxxx xxxx xxxx xxxx xxx1 xxxx
+ */
+ DECODE_TABLE (0x0f000010, 0x06000010, arm_cccc_0110_____xxx1_table),
+ DECODE_TABLE (0x0f000010, 0x07000010, arm_cccc_0111_____xxx1_table),
+
+ /*
+ * Load/store word and unsigned byte
+ * cccc 01xx xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0x0c000000, 0x04000000, arm_cccc_01xx_table),
+
+ /*
+ * Block data transfer instructions
+ * cccc 100x xxxx xxxx xxxx xxxx xxxx xxxx
+ */
+ DECODE_TABLE (0x0e000000, 0x08000000, arm_cccc_100x_table),
+
+ /* B cccc 1010 xxxx xxxx xxxx xxxx xxxx xxxx */
+ /* BL cccc 1011 xxxx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_SIMULATE (0x0e000000, 0x0a000000, PROBES_BRANCH),
+
+ /*
+ * Supervisor Call, and coprocessor instructions
+ */
+
+ /* MCRR cccc 1100 0100 xxxx xxxx xxxx xxxx xxxx */
+ /* MRRC cccc 1100 0101 xxxx xxxx xxxx xxxx xxxx */
+ /* LDC cccc 110x xxx1 xxxx xxxx xxxx xxxx xxxx */
+ /* STC cccc 110x xxx0 xxxx xxxx xxxx xxxx xxxx */
+ /* CDP cccc 1110 xxxx xxxx xxxx xxxx xxx0 xxxx */
+ /* MCR cccc 1110 xxx0 xxxx xxxx xxxx xxx1 xxxx */
+ /* MRC cccc 1110 xxx1 xxxx xxxx xxxx xxx1 xxxx */
+ /* SVC cccc 1111 xxxx xxxx xxxx xxxx xxxx xxxx */
+ DECODE_REJECT (0x0c000000, 0x0c000000),
+
+ DECODE_END
+};
+#ifdef CONFIG_ARM_KPROBES_TEST_MODULE
+EXPORT_SYMBOL_GPL(probes_decode_arm_table);
+#endif
+
+static void __kprobes arm_singlestep(probes_opcode_t insn,
+ struct arch_probes_insn *asi, struct pt_regs *regs)
+{
+ regs->ARM_pc += 4;
+ asi->insn_handler(insn, asi, regs);
+}
+
+/* Return:
+ * INSN_REJECTED If instruction is one not allowed to kprobe,
+ * INSN_GOOD If instruction is supported and uses instruction slot,
+ * INSN_GOOD_NO_SLOT If instruction is supported but doesn't use its slot.
+ *
+ * For instructions we don't want to kprobe (INSN_REJECTED return result):
+ * These are generally ones that modify the processor state making
+ * them "hard" to simulate such as switches processor modes or
+ * make accesses in alternate modes. Any of these could be simulated
+ * if the work was put into it, but low return considering they
+ * should also be very rare.
+ */
+enum probes_insn __kprobes
+arm_probes_decode_insn(probes_opcode_t insn, struct arch_probes_insn *asi,
+ bool emulate, const union decode_action *actions,
+ const struct decode_checker *checkers[])
+{
+ asi->insn_singlestep = arm_singlestep;
+ asi->insn_check_cc = probes_condition_checks[insn>>28];
+ return probes_decode_insn(insn, asi, probes_decode_arm_table, false,
+ emulate, actions, checkers);
+}