kernel-ark/arch/ia64/kernel/mca_drv_asm.S
Russ Anderson b1b901c202 [IA64] MCA recovery improvements
Jack Steiner uncovered some opportunities for improvement in
the MCA recovery code.

  1) Set bsp to save registers on the kernel stack.
  2) Disable interrupts while in the MCA recovery code.
  3) Change the way the user process is killed, to avoid 
     a panic in schedule.

Testing shows that these changes make the recovery code much 
more reliable with the 2.6.12 kernel.

Signed-off-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
2005-05-03 13:47:42 -07:00

58 lines
1.1 KiB
ArmAsm

/*
* File: mca_drv_asm.S
* Purpose: Assembly portion of Generic MCA handling
*
* Copyright (C) 2004 FUJITSU LIMITED
* Copyright (C) Hidetoshi Seto (seto.hidetoshi@jp.fujitsu.com)
*/
#include <linux/config.h>
#include <linux/threads.h>
#include <asm/asmmacro.h>
#include <asm/processor.h>
#include <asm/ptrace.h>
GLOBAL_ENTRY(mca_handler_bhhook)
invala // clear RSE ?
;; //
cover //
;; //
clrrrb //
;;
alloc r16=ar.pfs,0,2,1,0 // make a new frame
;;
mov ar.rsc=0
;;
mov r13=IA64_KR(CURRENT) // current task pointer
;;
mov r2=r13
;;
addl r22=IA64_RBS_OFFSET,r2
;;
mov ar.bspstore=r22
;;
addl sp=IA64_STK_OFFSET-IA64_PT_REGS_SIZE,r2
;;
adds r2=IA64_TASK_THREAD_ON_USTACK_OFFSET,r13
;;
st1 [r2]=r0 // clear current->thread.on_ustack flag
mov loc0=r16
movl loc1=mca_handler_bh // recovery C function
;;
mov out0=r8 // poisoned address
mov b6=loc1
;;
mov loc1=rp
;;
ssm psr.i
;;
br.call.sptk.many rp=b6 // does not return ...
;;
mov ar.pfs=loc0
mov rp=loc1
;;
mov r8=r0
br.ret.sptk.many rp
;;
END(mca_handler_bhhook)