From 453b7740ebfda2d84be7fb583c54f0c91c592869 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Tue, 26 Feb 2019 15:06:42 +0000 Subject: [PATCH] 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 Signed-off-by: Will Deacon --- arch/arm64/include/asm/brk-imm.h | 4 ++++ arch/arm64/include/asm/debug-monitors.h | 7 ++----- arch/arm64/include/asm/esr.h | 4 +--- arch/arm64/kernel/debug-monitors.c | 2 +- arch/arm64/kernel/probes/kprobes.c | 2 +- arch/arm64/kernel/probes/uprobes.c | 2 +- arch/arm64/kernel/traps.c | 2 +- 7 files changed, 11 insertions(+), 12 deletions(-) diff --git a/arch/arm64/include/asm/brk-imm.h b/arch/arm64/include/asm/brk-imm.h index fec9e1384641..d84294064e6a 100644 --- a/arch/arm64/include/asm/brk-imm.h +++ b/arch/arm64/include/asm/brk-imm.h @@ -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 diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h index 7d37cfa5cc16..0679f781696d 100644 --- a/arch/arm64/include/asm/debug-monitors.h +++ b/arch/arm64/include/asm/debug-monitors.h @@ -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 diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index 52233f00d53d..3541720189c9 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -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 diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c index f4d8cda8830d..2692a0a27cf3 100644 --- a/arch/arm64/kernel/debug-monitors.c +++ b/arch/arm64/kernel/debug-monitors.c @@ -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; diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index 000f32d1a756..2509fcb6d404 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -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, }; diff --git a/arch/arm64/kernel/probes/uprobes.c b/arch/arm64/kernel/probes/uprobes.c index f37ab9567676..605945eac1f8 100644 --- a/arch/arm64/kernel/probes/uprobes.c +++ b/arch/arm64/kernel/probes/uprobes.c @@ -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, }; diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c index 091379744d2f..74598396e0bf 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -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; -- 2.30.2