[xtensa-cvscommit] linux/arch/xtensa/kernel signal.c,1.4,1.5

[<ma...@us...>]

Update of /cvsroot/xtensa/linux/arch/xtensa/kernel
In directory sc8-pr-cvs1:/tmp/cvs-serv25303

Modified Files:
	signal.c 
Log Message:
Avoid overwriting the save area below user SP when generating signal frames.



Index: signal.c
===================================================================
RCS file: /cvsroot/xtensa/linux/arch/xtensa/kernel/signal.c,v
retrieving revision 1.4
retrieving revision 1.5
diff -C2 -d -r1.4 -r1.5
*** signal.c	20 Mar 2003 20:41:09 -0000	1.4
--- signal.c	22 Apr 2003 21:36:13 -0000	1.5
***************
*** 31,34 ****
--- 31,40 ----
  #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
  
+ /*
+  *  Number of bytes reserved below the stack pointer
+  *  (16 bytes for caller's a0-a3 save area, 16 bytes for misc
+  *  uses such as nested C function call chain pointer:  */
+ #define XTENSA_RESERVED_BELOW_SP	32
+ 
  asmlinkage long sys_wait4(pid_t pid,unsigned int * stat_addr, int options, struct rusage * ru);
  asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);
***************
*** 402,405 ****
--- 408,413 ----
  	if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! on_sig_stack(sp))
  		sp = current->sas_ss_sp + current->sas_ss_size;
+ 	else
+ 		sp -= XTENSA_RESERVED_BELOW_SP;
  
  	return (void *)((sp - frame_size) & -16ul);