diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-29 16:53:48 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-29 16:53:48 -0700 |
commit | 12679a2d7e3bfbdc7586e3e86d1ca90c46659363 (patch) | |
tree | d9c00f2e599d1c3e04a349229a6a19906d01f99e /arch/arm/kernel/kprobes.c | |
parent | 1c036588772d01655d851f75dffc27c971e072e2 (diff) | |
parent | b0df89868006517417251e02cc4ce5d4b0165885 (diff) |
Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm
Pull more ARM updates from Russell King.
This got a fair number of conflicts with the <asm/system.h> split, but
also with some other sparse-irq and header file include cleanups. They
all looked pretty trivial, though.
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits)
ARM: fix Kconfig warning for HAVE_BPF_JIT
ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds
ARM: 7349/1: integrator: convert to sparse irqs
ARM: 7259/3: net: JIT compiler for packet filters
ARM: 7334/1: add jump label support
ARM: 7333/2: jump label: detect %c support for ARM
ARM: 7338/1: add support for early console output via semihosting
ARM: use set_current_blocked() and block_sigmask()
ARM: exec: remove redundant set_fs(USER_DS)
ARM: 7332/1: extract out code patch function from kprobes
ARM: 7331/1: extract out insn generation code from ftrace
ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format
ARM: 7351/1: ftrace: remove useless memory checks
ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path
ARM: Versatile Express: add NO_IOPORT
ARM: get rid of asm/irq.h in asm/prom.h
ARM: 7319/1: Print debug info for SIGBUS in user faults
ARM: 7318/1: gic: refactor irq_start assignment
ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop
ARM: 7315/1: perf: add support for the Cortex-A7 PMU
...
Diffstat (limited to 'arch/arm/kernel/kprobes.c')
-rw-r--r-- | arch/arm/kernel/kprobes.c | 86 |
1 files changed, 24 insertions, 62 deletions
diff --git a/arch/arm/kernel/kprobes.c b/arch/arm/kernel/kprobes.c index 129c1163248b..ab1869dac97a 100644 --- a/arch/arm/kernel/kprobes.c +++ b/arch/arm/kernel/kprobes.c @@ -29,6 +29,7 @@ #include <asm/cacheflush.h> #include "kprobes.h" +#include "patch.h" #define MIN_STACK_SIZE(addr) \ min((unsigned long)MAX_STACK_SIZE, \ @@ -103,57 +104,33 @@ int __kprobes arch_prepare_kprobe(struct kprobe *p) return 0; } -#ifdef CONFIG_THUMB2_KERNEL - -/* - * For a 32-bit Thumb breakpoint spanning two memory words we need to take - * special precautions to insert the breakpoint atomically, especially on SMP - * systems. This is achieved by calling this arming function using stop_machine. - */ -static int __kprobes set_t32_breakpoint(void *addr) -{ - ((u16 *)addr)[0] = KPROBE_THUMB32_BREAKPOINT_INSTRUCTION >> 16; - ((u16 *)addr)[1] = KPROBE_THUMB32_BREAKPOINT_INSTRUCTION & 0xffff; - flush_insns(addr, 2*sizeof(u16)); - return 0; -} - void __kprobes arch_arm_kprobe(struct kprobe *p) { - uintptr_t addr = (uintptr_t)p->addr & ~1; /* Remove any Thumb flag */ - - if (!is_wide_instruction(p->opcode)) { - *(u16 *)addr = KPROBE_THUMB16_BREAKPOINT_INSTRUCTION; - flush_insns(addr, sizeof(u16)); - } else if (addr & 2) { - /* A 32-bit instruction spanning two words needs special care */ - stop_machine(set_t32_breakpoint, (void *)addr, &cpu_online_map); + unsigned int brkp; + void *addr; + + if (IS_ENABLED(CONFIG_THUMB2_KERNEL)) { + /* Remove any Thumb flag */ + addr = (void *)((uintptr_t)p->addr & ~1); + + if (is_wide_instruction(p->opcode)) + brkp = KPROBE_THUMB32_BREAKPOINT_INSTRUCTION; + else + brkp = KPROBE_THUMB16_BREAKPOINT_INSTRUCTION; } else { - /* Word aligned 32-bit instruction can be written atomically */ - u32 bkp = KPROBE_THUMB32_BREAKPOINT_INSTRUCTION; -#ifndef __ARMEB__ /* Swap halfwords for little-endian */ - bkp = (bkp >> 16) | (bkp << 16); -#endif - *(u32 *)addr = bkp; - flush_insns(addr, sizeof(u32)); - } -} + kprobe_opcode_t insn = p->opcode; -#else /* !CONFIG_THUMB2_KERNEL */ + addr = p->addr; + brkp = KPROBE_ARM_BREAKPOINT_INSTRUCTION; -void __kprobes arch_arm_kprobe(struct kprobe *p) -{ - kprobe_opcode_t insn = p->opcode; - kprobe_opcode_t brkp = KPROBE_ARM_BREAKPOINT_INSTRUCTION; - if (insn >= 0xe0000000) - brkp |= 0xe0000000; /* Unconditional instruction */ - else - brkp |= insn & 0xf0000000; /* Copy condition from insn */ - *p->addr = brkp; - flush_insns(p->addr, sizeof(p->addr[0])); -} + if (insn >= 0xe0000000) + brkp |= 0xe0000000; /* Unconditional instruction */ + else + brkp |= insn & 0xf0000000; /* Copy condition from insn */ + } -#endif /* !CONFIG_THUMB2_KERNEL */ + patch_text(addr, brkp); +} /* * The actual disarming is done here on each CPU and synchronized using @@ -166,25 +143,10 @@ void __kprobes arch_arm_kprobe(struct kprobe *p) int __kprobes __arch_disarm_kprobe(void *p) { struct kprobe *kp = p; -#ifdef CONFIG_THUMB2_KERNEL - u16 *addr = (u16 *)((uintptr_t)kp->addr & ~1); - kprobe_opcode_t insn = kp->opcode; - unsigned int len; + void *addr = (void *)((uintptr_t)kp->addr & ~1); - if (is_wide_instruction(insn)) { - ((u16 *)addr)[0] = insn>>16; - ((u16 *)addr)[1] = insn; - len = 2*sizeof(u16); - } else { - ((u16 *)addr)[0] = insn; - len = sizeof(u16); - } - flush_insns(addr, len); + __patch_text(addr, kp->opcode); -#else /* !CONFIG_THUMB2_KERNEL */ - *kp->addr = kp->opcode; - flush_insns(kp->addr, sizeof(kp->addr[0])); -#endif return 0; } |