forked from mirrors/linux
		
	MIPS: ftrace: Fix icache flush range error
In 32-bit mode, the start address passed to flush_icache_range is shifted by 4 bytes before the second safe_store_code() call. This causes system crash from time to time because the first 4 bytes might not be flushed properly. This bug exists since linux-3.8. Also remove obsoleted comment while at it. Signed-off-by: Viller Hsiao <villerhsiao@gmail.com> Cc: linux-mips@linux-mips.org Cc: rostedt@goodmis.org Cc: fweisbec@gmail.com Cc: mingo@redhat.com Cc: Qais.Yousef@imgtec.com Patchwork: https://patchwork.linux-mips.org/patch/6586/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
		
							parent
							
								
									86ca57b5a5
								
							
						
					
					
						commit
						a467109422
					
				
					 1 changed files with 2 additions and 3 deletions
				
			
		| 
						 | 
					@ -111,11 +111,10 @@ static int ftrace_modify_code_2(unsigned long ip, unsigned int new_code1,
 | 
				
			||||||
	safe_store_code(new_code1, ip, faulted);
 | 
						safe_store_code(new_code1, ip, faulted);
 | 
				
			||||||
	if (unlikely(faulted))
 | 
						if (unlikely(faulted))
 | 
				
			||||||
		return -EFAULT;
 | 
							return -EFAULT;
 | 
				
			||||||
	ip += 4;
 | 
						safe_store_code(new_code2, ip + 4, faulted);
 | 
				
			||||||
	safe_store_code(new_code2, ip, faulted);
 | 
					 | 
				
			||||||
	if (unlikely(faulted))
 | 
						if (unlikely(faulted))
 | 
				
			||||||
		return -EFAULT;
 | 
							return -EFAULT;
 | 
				
			||||||
	flush_icache_range(ip, ip + 8); /* original ip + 12 */
 | 
						flush_icache_range(ip, ip + 8);
 | 
				
			||||||
	return 0;
 | 
						return 0;
 | 
				
			||||||
}
 | 
					}
 | 
				
			||||||
#endif
 | 
					#endif
 | 
				
			||||||
| 
						 | 
					
 | 
				
			||||||
		Loading…
	
		Reference in a new issue