[v3,13/15] ARM: Add an emulate flag to the kprobes/uprobes instruction decode functions

Message ID	1385520814-10663-14-git-send-email-dave.long@linaro.org (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org> From: David Long <dave.long@linaro.org> To: linux-arm-kernel@lists.infradead.org, Russell King <linux@arm.linux.org.uk> Subject: [PATCH v3 13/15] ARM: Add an emulate flag to the kprobes/uprobes instruction decode functions Date: Tue, 26 Nov 2013 21:53:32 -0500 Message-Id: <1385520814-10663-14-git-send-email-dave.long@linaro.org> In-Reply-To: <1385520814-10663-1-git-send-email-dave.long@linaro.org> References: <1385520814-10663-1-git-send-email-dave.long@linaro.org> Cc: "Jon Medhurst \(Tixy\)" <tixy@linaro.org>, Peter Zijlstra <a.p.zijlstra@chello.nl>, Srikar Dronamraju <srikar@linux.vnet.ibm.com>, Oleg Nesterov <oleg@redhat.com>, Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>, linux-kernel@vger.kernel.org, Rabin Vincent <rabin@rab.in>, Ingo Molnar <mingo@redhat.com>, Paul Mackerras <paulus@samba.org>, Arnaldo Carvalho de Melo <acme@ghostprotocols.net>, Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>, davem@davemloft.net, Ananth N Mavinakayanahalli <ananth@in.ibm.com> Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" <linux-arm-kernel-bounces@lists.infradead.org> Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org

diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index 0d9d49b..04690f9 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -87,7 +87,8 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) p->opcode = insn; p->ainsn.insn = tmp_insn; - switch ((*decode_insn)(insn, &p->ainsn, actions)) { + switch ((*decode_insn)(insn, &p->ainsn, + true, actions)) { case INSN_REJECTED: /* not supported */ return -EINVAL; diff --git a/arch/arm/kernel/kprobes.h b/arch/arm/kernel/kprobes.h index e1305a8..580d82c 100644 --- a/arch/arm/kernel/kprobes.h +++ b/arch/arm/kernel/kprobes.h @@ -35,6 +35,7 @@ kprobe_decode_ldmstm(kprobe_opcode_t insn, struct arch_specific_insn *asi, typedef enum probes_insn (kprobe_decode_insn_t)(kprobe_opcode_t, struct arch_specific_insn *, + bool, const union decode_item *); #ifdef CONFIG_THUMB2_KERNEL diff --git a/arch/arm/kernel/probes-arm.c b/arch/arm/kernel/probes-arm.c index a44c3ad..01e99f7 100644 --- a/arch/arm/kernel/probes-arm.c +++ b/arch/arm/kernel/probes-arm.c @@ -723,10 +723,10 @@ static void __kprobes arm_singlestep(probes_opcode_t insn, */ enum probes_insn __kprobes arm_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *actions) + bool emulate, const union decode_item *actions) { 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, - actions); + emulate, actions); } diff --git a/arch/arm/kernel/probes-arm.h b/arch/arm/kernel/probes-arm.h index 7f81199..904033c 100644 --- a/arch/arm/kernel/probes-arm.h +++ b/arch/arm/kernel/probes-arm.h @@ -66,7 +66,7 @@ void __kprobes simulate_mov_ipsp(probes_opcode_t opcode, extern const union decode_item probes_decode_arm_table[]; enum probes_insn arm_probes_decode_insn(probes_opcode_t, - struct arch_specific_insn *, + struct arch_specific_insn *, bool emulate, const union decode_item *actions); #endif diff --git a/arch/arm/kernel/probes-thumb.c b/arch/arm/kernel/probes-thumb.c index 3f250e9..2ad0880 100644 --- a/arch/arm/kernel/probes-thumb.c +++ b/arch/arm/kernel/probes-thumb.c @@ -861,20 +861,20 @@ static void __kprobes thumb32_singlestep(probes_opcode_t opcode, enum probes_insn __kprobes thumb16_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *actions) + bool emulate, const union decode_item *actions) { asi->insn_singlestep = thumb16_singlestep; asi->insn_check_cc = thumb_check_cc; return probes_decode_insn(insn, asi, probes_decode_thumb16_table, true, - actions); + emulate, actions); } enum probes_insn __kprobes thumb32_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *actions) + bool emulate, const union decode_item *actions) { asi->insn_singlestep = thumb32_singlestep; asi->insn_check_cc = thumb_check_cc; return probes_decode_insn(insn, asi, probes_decode_thumb32_table, true, - actions); + emulate, actions); } diff --git a/arch/arm/kernel/probes-thumb.h b/arch/arm/kernel/probes-thumb.h index 556f067..78be667 100644 --- a/arch/arm/kernel/probes-thumb.h +++ b/arch/arm/kernel/probes-thumb.h @@ -87,9 +87,9 @@ extern const union decode_item probes_decode_thumb16_table[]; enum probes_insn __kprobes thumb16_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *actions); + bool emulate, const union decode_item *actions); enum probes_insn __kprobes thumb32_probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *actions); + bool emulate, const union decode_item *actions); #endif diff --git a/arch/arm/kernel/probes.c b/arch/arm/kernel/probes.c index a0a4220..e691e12 100644 --- a/arch/arm/kernel/probes.c +++ b/arch/arm/kernel/probes.c @@ -193,7 +193,7 @@ void __kprobes probes_emulate_none(probes_opcode_t opcode, */ static probes_opcode_t __kprobes prepare_emulated_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - bool thumb) + bool thumb) { #ifdef CONFIG_THUMB2_KERNEL if (thumb) { @@ -218,7 +218,7 @@ prepare_emulated_insn(probes_opcode_t insn, struct arch_specific_insn *asi, */ static void __kprobes set_emulated_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - bool thumb) + bool thumb) { #ifdef CONFIG_THUMB2_KERNEL if (thumb) { @@ -253,7 +253,7 @@ set_emulated_insn(probes_opcode_t insn, struct arch_specific_insn *asi, * non-zero value, the corresponding nibble in pinsn is validated and modified * according to the type. */ -static bool __kprobes decode_regs(probes_opcode_t *pinsn, u32 regs) +static bool __kprobes decode_regs(probes_opcode_t *pinsn, u32 regs, bool modify) { probes_opcode_t insn = *pinsn; probes_opcode_t mask = 0xf; /* Start at least significant nibble */ @@ -317,9 +317,16 @@ static bool __kprobes decode_regs(probes_opcode_t *pinsn, u32 regs) /* Replace value of nibble with new register number... */ insn &= ~mask; insn |= new_bits & mask; + if (modify) { + /* Replace value of nibble with new register number */ + insn &= ~mask; + insn |= new_bits & mask; + } } - *pinsn = insn; + if (modify) + *pinsn = insn; + return true; reject: @@ -380,14 +387,15 @@ static const int decode_struct_sizes[NUM_DECODE_TYPES] = { */ int __kprobes probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *table, bool thumb, - const union decode_item *actions) + const union decode_item *table, bool thumb, + bool emulate, const union decode_item *actions) { struct decode_header *h = (struct decode_header *)table; struct decode_header *next; bool matched = false; - insn = prepare_emulated_insn(insn, asi, thumb); + if (emulate) + insn = prepare_emulated_insn(insn, asi, thumb); for (;; h = next) { enum decode_type type = h->type_regs.bits & DECODE_TYPE_MASK; @@ -402,7 +410,7 @@ probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, if (!matched && (insn & h->mask.bits) != h->value.bits) continue; - if (!decode_regs(&insn, regs)) + if (!decode_regs(&insn, regs, emulate)) return INSN_REJECTED; switch (type) { @@ -415,7 +423,8 @@ probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, case DECODE_TYPE_CUSTOM: { struct decode_custom *d = (struct decode_custom *)h; - return actions[d->decoder.bits].decoder(insn, asi, h); + return actions[d->decoder.bits].decoder(insn, + asi, h); } case DECODE_TYPE_SIMULATE: { @@ -426,6 +435,11 @@ probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, case DECODE_TYPE_EMULATE: { struct decode_emulate *d = (struct decode_emulate *)h; + + if (!emulate) + return actions[d->handler.bits].decoder(insn, + asi, h); + asi->insn_handler = actions[d->handler.bits].handler; set_emulated_insn(insn, asi, thumb); return INSN_GOOD; diff --git a/arch/arm/kernel/probes.h b/arch/arm/kernel/probes.h index 9591c2c..233ab7b 100644 --- a/arch/arm/kernel/probes.h +++ b/arch/arm/kernel/probes.h @@ -389,7 +389,7 @@ probes_insn_handler_t probes_emulate_none; int __kprobes probes_decode_insn(probes_opcode_t insn, struct arch_specific_insn *asi, - const union decode_item *table, bool thumb, + const union decode_item *table, bool thumb, bool emulate, const union decode_item *actions); #endif

[v3,13/15] ARM: Add an emulate flag to the kprobes/uprobes instruction decode functions

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Patch