From: "tip-bot2 for Peter Zijlstra" <tip-bot2@linutronix.de>
To: linux-tip-commits@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>,
"Steven Rostedt (VMware)" <rostedt@goodmis.org>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Andy Lutomirski <luto@kernel.org>, Borislav Petkov <bp@alien8.de>,
Daniel Bristot de Oliveira <bristot@redhat.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Josh Poimboeuf <jpoimboe@redhat.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Masami Hiramatsu <mhiramat@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@kernel.org>, x86 <x86@kernel.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: [tip: core/kprobes] x86/alternatives: Add and use text_gen_insn() helper
Date: Wed, 04 Dec 2019 08:33:37 -0000 [thread overview]
Message-ID: <157544841740.21853.15156880093439418685.tip-bot2@tip-bot2> (raw)
In-Reply-To: <20191111132457.703538332@infradead.org>
The following commit has been merged into the core/kprobes branch of tip:
Commit-ID: 63f62addb88ec4b358cf4574789bc3180c689e9a
Gitweb: https://git.kernel.org/tip/63f62addb88ec4b358cf4574789bc3180c689e9a
Author: Peter Zijlstra <peterz@infradead.org>
AuthorDate: Thu, 03 Oct 2019 14:50:42 +02:00
Committer: Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 27 Nov 2019 07:44:24 +01:00
x86/alternatives: Add and use text_gen_insn() helper
Provide a simple helper function to create common instruction
encodings.
Tested-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111132457.703538332@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/include/asm/text-patching.h | 2 ++-
arch/x86/kernel/alternative.c | 36 +++++++++++++++++++++++++++-
arch/x86/kernel/jump_label.c | 31 ++++++++---------------
arch/x86/kernel/kprobes/opt.c | 7 +-----
4 files changed, 50 insertions(+), 26 deletions(-)
diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h
index 3bcd266..95beb85 100644
--- a/arch/x86/include/asm/text-patching.h
+++ b/arch/x86/include/asm/text-patching.h
@@ -49,6 +49,8 @@ extern void text_poke_bp(void *addr, const void *opcode, size_t len, const void
extern void text_poke_queue(void *addr, const void *opcode, size_t len, const void *emulate);
extern void text_poke_finish(void);
+extern void *text_gen_insn(u8 opcode, const void *addr, const void *dest);
+
extern int after_bootmem;
extern __ro_after_init struct mm_struct *poking_mm;
extern __ro_after_init unsigned long poking_addr;
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index 42e7f0a..714b4a2 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -1237,3 +1237,39 @@ void text_poke_bp(void *addr, const void *opcode, size_t len, const void *emulat
text_poke_loc_init(&tp, addr, opcode, len, emulate);
text_poke_bp_batch(&tp, 1);
}
+
+union text_poke_insn {
+ u8 text[POKE_MAX_OPCODE_SIZE];
+ struct {
+ u8 opcode;
+ s32 disp;
+ } __attribute__((packed));
+};
+
+void *text_gen_insn(u8 opcode, const void *addr, const void *dest)
+{
+ static union text_poke_insn insn; /* text_mutex */
+ int size = 0;
+
+ lockdep_assert_held(&text_mutex);
+
+ insn.opcode = opcode;
+
+#define __CASE(insn) \
+ case insn##_INSN_OPCODE: size = insn##_INSN_SIZE; break
+
+ switch(opcode) {
+ __CASE(INT3);
+ __CASE(CALL);
+ __CASE(JMP32);
+ __CASE(JMP8);
+ }
+
+ if (size > 1) {
+ insn.disp = (long)dest - (long)(addr + size);
+ if (size == 2)
+ BUG_ON((insn.disp >> 31) != (insn.disp >> 7));
+ }
+
+ return &insn.text;
+}
diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index cf8c847..9c4498e 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -16,15 +16,7 @@
#include <asm/alternative.h>
#include <asm/text-patching.h>
-union jump_code_union {
- char code[JUMP_LABEL_NOP_SIZE];
- struct {
- char jump;
- int offset;
- } __attribute__((packed));
-};
-
-static void bug_at(unsigned char *ip, int line)
+static void bug_at(const void *ip, int line)
{
/*
* The location is not an op that we were expecting.
@@ -38,33 +30,32 @@ static void bug_at(unsigned char *ip, int line)
static const void *
__jump_label_set_jump_code(struct jump_entry *entry, enum jump_label_type type, int init)
{
- static union jump_code_union code; /* relies on text_mutex */
const unsigned char default_nop[] = { STATIC_KEY_INIT_NOP };
const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
- const void *expect;
+ const void *expect, *code;
+ const void *addr, *dest;
int line;
- lockdep_assert_held(&text_mutex);
+ addr = (void *)jump_entry_code(entry);
+ dest = (void *)jump_entry_target(entry);
- code.jump = JMP32_INSN_OPCODE;
- code.offset = jump_entry_target(entry) -
- (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
+ code = text_gen_insn(JMP32_INSN_OPCODE, addr, dest);
if (init) {
expect = default_nop; line = __LINE__;
} else if (type == JUMP_LABEL_JMP) {
expect = ideal_nop; line = __LINE__;
} else {
- expect = code.code; line = __LINE__;
+ expect = code; line = __LINE__;
}
- if (memcmp((void *)jump_entry_code(entry), expect, JUMP_LABEL_NOP_SIZE))
- bug_at((void *)jump_entry_code(entry), line);
+ if (memcmp(addr, expect, JUMP_LABEL_NOP_SIZE))
+ bug_at(addr, line);
if (type == JUMP_LABEL_NOP)
- memcpy(&code, ideal_nop, JUMP_LABEL_NOP_SIZE);
+ code = ideal_nop;
- return &code;
+ return code;
}
static void inline __jump_label_transform(struct jump_entry *entry,
diff --git a/arch/x86/kernel/kprobes/opt.c b/arch/x86/kernel/kprobes/opt.c
index 8900329..9b01ee7 100644
--- a/arch/x86/kernel/kprobes/opt.c
+++ b/arch/x86/kernel/kprobes/opt.c
@@ -447,18 +447,13 @@ void arch_optimize_kprobes(struct list_head *oplist)
void arch_unoptimize_kprobe(struct optimized_kprobe *op)
{
u8 insn_buff[RELATIVEJUMP_SIZE];
- u8 emulate_buff[RELATIVEJUMP_SIZE];
/* Set int3 to first byte for kprobes */
insn_buff[0] = BREAKPOINT_INSTRUCTION;
memcpy(insn_buff + 1, op->optinsn.copied_insn, RELATIVE_ADDR_SIZE);
- emulate_buff[0] = RELATIVEJUMP_OPCODE;
- *(s32 *)(&emulate_buff[1]) = (s32)((long)op->optinsn.insn -
- ((long)op->kp.addr + RELATIVEJUMP_SIZE));
-
text_poke_bp(op->kp.addr, insn_buff, RELATIVEJUMP_SIZE,
- emulate_buff);
+ text_gen_insn(JMP32_INSN_OPCODE, op->kp.addr, op->optinsn.insn));
}
/*
next prev parent reply other threads:[~2019-12-04 8:34 UTC|newest]
Thread overview: 106+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-11-11 13:12 [PATCH -v5 00/17] Rewrite x86/ftrace to use text_poke (and more) Peter Zijlstra
2019-11-11 13:12 ` [PATCH -v5 01/17] x86/alternatives: Teach text_poke_bp() to emulate instructions Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-11-11 13:12 ` [PATCH -v5 02/17] x86/alternatives: Update int3_emulate_push() comment Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:12 ` [PATCH -v5 03/17] x86/alternatives,jump_label: Provide better text_poke() batching interface Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] x86/alternatives, jump_label: " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:12 ` [PATCH -v5 04/17] x86/alternatives: Add and use text_gen_insn() helper Peter Zijlstra
2019-11-12 17:10 ` Steven Rostedt
2019-11-12 22:25 ` Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra [this message]
2019-11-11 13:12 ` [PATCH -v5 05/17] x86/ftrace: Use text_poke() Peter Zijlstra
2019-11-12 18:25 ` Steven Rostedt
2019-11-12 22:24 ` Peter Zijlstra
2019-11-12 22:48 ` Steven Rostedt
2019-11-13 9:01 ` Peter Zijlstra
2019-11-13 14:27 ` Steven Rostedt
2019-11-14 13:18 ` Peter Zijlstra
2019-11-14 13:56 ` Steven Rostedt
2019-11-14 14:05 ` Peter Zijlstra
2019-11-13 8:53 ` Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-11-16 20:46 ` Borislav Petkov
2019-11-18 17:35 ` [PATCH] x86/ftrace: Mark ftrace_modify_code_direct() __ref Borislav Petkov
2019-11-18 17:52 ` Steven Rostedt
2019-11-19 9:55 ` [tip: core/kprobes] " tip-bot2 for Borislav Petkov
2019-12-04 8:33 ` tip-bot2 for Borislav Petkov
2019-12-04 8:33 ` [tip: core/kprobes] x86/ftrace: Use text_poke() tip-bot2 for Peter Zijlstra
2019-11-11 13:12 ` [PATCH -v5 06/17] x86/mm: Remove set_kernel_text_r[ow]() Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:12 ` [PATCH -v5 07/17] x86/alternative: Add text_opcode_size() Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 08/17] x86/ftrace: Use text_gen_insn() Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 09/17] x86/alternative: Remove text_poke_loc::len Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 10/17] x86/alternative: Shrink text_poke_loc Peter Zijlstra
2019-11-15 9:43 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 11/17] x86/kprobes: Convert to text-patching.h Peter Zijlstra
2019-11-19 16:56 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 12/17] x86/kprobes: Fix ordering Peter Zijlstra
2019-11-13 14:31 ` Paul E. McKenney
2019-11-13 15:42 ` Mathieu Desnoyers
2019-11-14 13:53 ` Peter Zijlstra
2019-11-14 15:06 ` Mathieu Desnoyers
2019-11-14 15:13 ` Paul E. McKenney
2019-11-14 15:22 ` Mathieu Desnoyers
2019-11-14 15:28 ` Peter Zijlstra
2019-11-14 15:30 ` Mathieu Desnoyers
2019-11-14 15:42 ` Peter Zijlstra
2019-11-14 15:58 ` Peter Zijlstra
2019-11-19 16:56 ` [tip: core/kprobes] x86/kprobes: Fix ordering while text-patching tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 13/17] arm/ftrace: Use __patch_text_real() Peter Zijlstra
2019-11-11 16:47 ` Will Deacon
2019-11-11 17:19 ` Peter Zijlstra
2019-11-11 17:25 ` Peter Zijlstra
2019-11-12 11:29 ` Will Deacon
2019-11-13 9:26 ` [PATCH -v5mkII 13/17] arm/ftrace: Use __patch_text() Peter Zijlstra
2019-11-19 16:56 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2020-01-22 21:26 ` Dmitry Osipenko
2020-02-07 10:17 ` Peter Zijlstra
2020-02-07 10:26 ` Peter Zijlstra
2020-02-07 11:27 ` Peter Zijlstra
2020-02-07 16:47 ` Dmitry Osipenko
2020-01-08 12:22 ` [PATCH -v5mkII 13/17] " Arnd Bergmann
2020-01-08 14:16 ` Steven Rostedt
2020-01-08 14:22 ` Arnd Bergmann
2019-11-11 13:13 ` [PATCH -v5 14/17] module: Remove set_all_modules_text_*() Peter Zijlstra
2019-11-19 16:56 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 15/17] ftrace: Rework event_create_dir() Peter Zijlstra
2019-11-14 14:07 ` Steven Rostedt
2019-11-19 16:56 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 16/17] x86/kprobe: Add comments to arch_{,un}optimize_kprobes() Peter Zijlstra
2019-11-19 16:56 ` [tip: core/kprobes] " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 13:13 ` [PATCH -v5 17/17] x86/alternative: Use INT3_INSN_SIZE Peter Zijlstra
2019-11-19 16:56 ` [tip: core/kprobes] x86/alternatives: " tip-bot2 for Peter Zijlstra
2019-12-04 8:33 ` tip-bot2 for Peter Zijlstra
2019-11-11 19:47 ` [PATCH -v5 00/17] Rewrite x86/ftrace to use text_poke (and more) Alexei Starovoitov
2019-11-11 20:39 ` Peter Zijlstra
2019-11-11 20:42 ` Peter Zijlstra
2019-11-11 20:56 ` Alexei Starovoitov
2019-11-12 18:26 ` Steven Rostedt
2019-11-25 3:55 ` Masami Hiramatsu
2019-11-25 6:47 ` Masami Hiramatsu
2019-11-25 17:32 ` Steven Rostedt
2019-11-26 0:11 ` Masami Hiramatsu
2019-11-26 8:58 ` Masami Hiramatsu
2019-11-26 9:58 ` Masami Hiramatsu
2019-11-26 23:48 ` Masami Hiramatsu
[not found] ` <CAADnVQK4twuXzFhD-qLHmCVK0n1h-GDENQLu+4PVV3Hp++R6kQ@mail.gmail.com>
2019-11-27 4:32 ` Alexei Starovoitov
2019-11-27 5:01 ` Alexei Starovoitov
2019-11-27 6:41 ` Masami Hiramatsu
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