Commit a2b53673 authored by Heiko Carstens's avatar Heiko Carstens Committed by Martin Schwidefsky
Browse files

[S390] kprobes: use probe_kernel_write

Use proble_kernel_write() to patch the kernel.
Signed-off-by: default avatarHeiko Carstens <>
Signed-off-by: default avatarMartin Schwidefsky <>
parent 88df125f
......@@ -25,9 +25,9 @@
#include <linux/preempt.h>
#include <linux/stop_machine.h>
#include <linux/kdebug.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/sections.h>
#include <asm/uaccess.h>
#include <linux/module.h>
DEFINE_PER_CPU(struct kprobe *, current_kprobe) = NULL;
......@@ -155,35 +155,8 @@ void __kprobes get_instruction_type(struct arch_specific_insn *ainsn)
static int __kprobes swap_instruction(void *aref)
struct ins_replace_args *args = aref;
u32 *addr;
u32 instr;
int err = -EFAULT;
* Text segment is read-only, hence we use stura to bypass dynamic
* address translation to exchange the instruction. Since stura
* always operates on four bytes, but we only want to exchange two
* bytes do some calculations to get things right. In addition we
* shall not cross any page boundaries (vmalloc area!) when writing
* the new instruction.
addr = (u32 *)((unsigned long)args->ptr & -4UL);
if ((unsigned long)args->ptr & 2)
instr = ((*addr) & 0xffff0000) | args->new;
instr = ((*addr) & 0x0000ffff) | args->new << 16;
asm volatile(
" lra %1,0(%1)\n"
"0: stura %2,%1\n"
"1: la %0,0\n"
: "+d" (err)
: "a" (addr), "d" (instr)
: "memory", "cc");
return err;
return probe_kernel_write(args->ptr, &args->new, sizeof(args->new));
void __kprobes arch_arm_kprobe(struct kprobe *p)
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