alpha: fix hae_cache race in RESTORE_ALL

[net-next-2.6.git] / arch / alpha / kernel / entry.S

diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index a3e9cd85cfee38d1cf08d7e80d79a84c678675c2..d1273c1a136420474ff7250414316ca511746b54 100644 (file)
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -73,8 +73,6 @@
        ldq     $20, HAE_REG($19);      \
        stq     $21, HAE_CACHE($19);    \
        stq     $21, 0($20);            \
-       ldq     $0, 0($sp);             \
-       ldq     $1, 8($sp);             \
 99:;                                   \
        ldq     $19, 72($sp);           \
        ldq     $20, 80($sp);           \
@@ -316,19 +314,24 @@ ret_from_sys_call:
        cmovne  $26, 0, $19             /* $19 = 0 => non-restartable */
        ldq     $0, SP_OFF($sp)
        and     $0, 8, $0
-       beq     $0, restore_all
-ret_from_reschedule:
+       beq     $0, ret_to_kernel
+ret_to_user:
        /* Make sure need_resched and sigpending don't change between
                sampling and the rti.  */
        lda     $16, 7
        call_pal PAL_swpipl
        ldl     $5, TI_FLAGS($8)
        and     $5, _TIF_WORK_MASK, $2
-       bne     $5, work_pending
+       bne     $2, work_pending
 restore_all:
        RESTORE_ALL
        call_pal PAL_rti
 
+ret_to_kernel:
+       lda     $16, 7
+       call_pal PAL_swpipl
+       br restore_all
+
        .align 3
 $syscall_error:
        /*
@@ -363,7 +366,7 @@ $ret_success:
  *       $8: current.
  *      $19: The old syscall number, or zero if this is not a return
  *           from a syscall that errored and is possibly restartable.
- *      $20: Error indication.
+ *      $20: The old a3 value
  */
 
        .align  4
@@ -392,12 +395,18 @@ $work_resched:
 
 $work_notifysig:
        mov     $sp, $16
-       br      $1, do_switch_stack
+       bsr     $1, do_switch_stack
        mov     $sp, $17
        mov     $5, $18
+       mov     $19, $9         /* save old syscall number */
+       mov     $20, $10        /* save old a3 */
+       and     $5, _TIF_SIGPENDING, $2
+       cmovne  $2, 0, $9       /* we don't want double syscall restarts */
        jsr     $26, do_notify_resume
+       mov     $9, $19
+       mov     $10, $20
        bsr     $1, undo_switch_stack
-       br      restore_all
+       br      ret_to_user
 .end work_pending
 
 /*
@@ -651,7 +660,7 @@ kernel_thread:
        /* We don't actually care for a3 success widgetry in the kernel.
           Not for positive errno values.  */
        stq     $0, 0($sp)              /* $0 */
-       br      restore_all
+       br      ret_to_kernel
 .end kernel_thread
 
 /*