| Message ID | 20190301132809.24653-10-will.deacon@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Rework debug exception handling code | expand |
On Fri, Mar 01, 2019 at 01:28:08PM +0000, Will Deacon wrote: > 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. > > Signed-off-by: Will Deacon <will.deacon@arm.com> Modulo the latent bug with KASAN immediates I mentioned in a prior patch: Reviewed-by: Mark Rutland <mark.rutland@arm.com> Mark. > --- > 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 2945fe6cd863..645ea26cca81 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 2b136f0f6a35..5a731757a3c4 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 d9616c34a270..55d46ed6ccc2 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) > - if ((esr & BRK64_ESR_MASK) == hook->imm) > + if ((esr & ESR_ELx_BRK64_ISS_COMMENT_MASK) == hook->imm) > fn = hook->fn; > rcu_read_unlock(); > > diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c > index 30502a3c8cf0..42a30f23b85f 100644 > --- a/arch/arm64/kernel/probes/kprobes.c > +++ b/arch/arm64/kernel/probes/kprobes.c > @@ -475,7 +475,7 @@ 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 3bcd56dd94fa..387c5e18cc46 100644 > --- a/arch/arm64/kernel/traps.c > +++ b/arch/arm64/kernel/traps.c > @@ -1019,7 +1019,7 @@ int __init early_brk64(unsigned long addr, unsigned int esr, > struct pt_regs *regs) > { > #ifdef CONFIG_KASAN_SW_TAGS > - if ((esr & BRK64_ESR_MASK) == KASAN_BRK_IMM) > + if ((esr & ESR_ELx_BRK64_ISS_COMMENT_MASK) == KASAN_BRK_IMM) > return kasan_handler(regs, esr) != DBG_HOOK_HANDLED; > #endif > return bug_handler(regs, esr) != DBG_HOOK_HANDLED; > -- > 2.11.0 >
diff --git a/arch/arm64/include/asm/brk-imm.h b/arch/arm64/include/asm/brk-imm.h index 2945fe6cd863..645ea26cca81 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 2b136f0f6a35..5a731757a3c4 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 d9616c34a270..55d46ed6ccc2 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) - if ((esr & BRK64_ESR_MASK) == hook->imm) + if ((esr & ESR_ELx_BRK64_ISS_COMMENT_MASK) == hook->imm) fn = hook->fn; rcu_read_unlock(); diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index 30502a3c8cf0..42a30f23b85f 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -475,7 +475,7 @@ 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 3bcd56dd94fa..387c5e18cc46 100644 --- a/arch/arm64/kernel/traps.c +++ b/arch/arm64/kernel/traps.c @@ -1019,7 +1019,7 @@ int __init early_brk64(unsigned long addr, unsigned int esr, struct pt_regs *regs) { #ifdef CONFIG_KASAN_SW_TAGS - if ((esr & BRK64_ESR_MASK) == KASAN_BRK_IMM) + if ((esr & ESR_ELx_BRK64_ISS_COMMENT_MASK) == KASAN_BRK_IMM) return kasan_handler(regs, esr) != DBG_HOOK_HANDLED; #endif return bug_handler(regs, esr) != DBG_HOOK_HANDLED;
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. Signed-off-by: Will Deacon <will.deacon@arm.com> --- 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(-)