arm64: probes: Move magic BRK values into brk-imm.h

kprobes and uprobes reserve some BRK immediates for installing their
probes. Define these along with the other reservations in brk-imm.h
and rename the ESR definitions to be consistent with the others that we
already have.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Will Deacon 2019-02-26 15:06:42 +00:00
parent fb610f2a20
commit 453b7740eb
7 changed files with 11 additions and 12 deletions

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@ -11,6 +11,8 @@
/*
* #imm16 values used for BRK instruction generation
* 0x004: for installing kprobes
* 0x005: for installing uprobes
* Allowed values for kgdb are 0x400 - 0x7ff
* 0x100: for triggering a fault on purpose (reserved)
* 0x400: for dynamic BRK instruction
@ -18,6 +20,8 @@
* 0x800: kernel-mode BUG() and WARN() traps
* 0x9xx: tag-based KASAN trap (allowed values 0x900 - 0x9ff)
*/
#define KPROBES_BRK_IMM 0x004
#define UPROBES_BRK_IMM 0x005
#define FAULT_BRK_IMM 0x100
#define KGDB_DYN_DBG_BRK_IMM 0x400
#define KGDB_COMPILED_DBG_BRK_IMM 0x401

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@ -65,12 +65,9 @@
#define CACHE_FLUSH_IS_SAFE 1
/* kprobes BRK opcodes with ESR encoding */
#define BRK64_ESR_MASK 0xFFFF
#define BRK64_ESR_KPROBES 0x0004
#define BRK64_OPCODE_KPROBES (AARCH64_BREAK_MON | (BRK64_ESR_KPROBES << 5))
#define BRK64_OPCODE_KPROBES (AARCH64_BREAK_MON | (KPROBES_BRK_IMM << 5))
/* uprobes BRK opcodes with ESR encoding */
#define BRK64_ESR_UPROBES 0x0005
#define BRK64_OPCODE_UPROBES (AARCH64_BREAK_MON | (BRK64_ESR_UPROBES << 5))
#define BRK64_OPCODE_UPROBES (AARCH64_BREAK_MON | (UPROBES_BRK_IMM << 5))
/* AArch32 */
#define DBG_ESR_EVT_BKPT 0x4

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@ -156,9 +156,7 @@
ESR_ELx_WFx_ISS_WFI)
/* BRK instruction trap from AArch64 state */
#define ESR_ELx_VAL_BRK64(imm) \
((ESR_ELx_EC_BRK64 << ESR_ELx_EC_SHIFT) | ESR_ELx_IL | \
((imm) & 0xffff))
#define ESR_ELx_BRK64_ISS_COMMENT_MASK 0xffff
/* ISS field definitions for System instruction traps */
#define ESR_ELx_SYS64_ISS_RES0_SHIFT 22

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@ -317,7 +317,7 @@ static int call_break_hook(struct pt_regs *regs, unsigned int esr)
rcu_read_lock();
list_for_each_entry_rcu(hook, list, node) {
unsigned int comment = esr & BRK64_ESR_MASK;
unsigned int comment = esr & ESR_ELx_BRK64_ISS_COMMENT_MASK;
if ((comment & ~hook->mask) == hook->imm)
fn = hook->fn;

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@ -470,7 +470,7 @@ kprobe_breakpoint_handler(struct pt_regs *regs, unsigned int esr)
}
static struct break_hook kprobes_break_hook = {
.imm = BRK64_ESR_KPROBES,
.imm = KPROBES_BRK_IMM,
.fn = kprobe_breakpoint_handler,
};

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@ -191,7 +191,7 @@ static int uprobe_single_step_handler(struct pt_regs *regs,
/* uprobe breakpoint handler hook */
static struct break_hook uprobes_break_hook = {
.imm = BRK64_ESR_UPROBES,
.imm = UPROBES_BRK_IMM,
.fn = uprobe_breakpoint_handler,
};

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@ -1024,7 +1024,7 @@ int __init early_brk64(unsigned long addr, unsigned int esr,
struct pt_regs *regs)
{
#ifdef CONFIG_KASAN_SW_TAGS
unsigned int comment = esr & BRK64_ESR_MASK;
unsigned int comment = esr & ESR_ELx_BRK64_ISS_COMMENT_MASK;
if ((comment & ~KASAN_BRK_MASK) == KASAN_BRK_IMM)
return kasan_handler(regs, esr) != DBG_HOOK_HANDLED;