13902 Fix for 13717 may break 8-disk raidz2

*** 1386,1405 ****
                          fp_save(&pl->lwp_pcb.pcb_fpu);
                  pl->lwp_pcb.pcb_fpu.fpu_flags |= FPU_KERNEL;
                  kpreempt_enable();
          }
  
-         /*
-          * Set the context operations for kernel FPU usage. Note that this
-          * cannot be done with pre-emption and interrupts disabled, since
-          * installctx does a sleeping allocation. We haven't finished
-          * initializing our kernel FPU state yet, but in the rare case that we
-          * happen to save/restore before that, no harm is done.
-          */
-         installctx(curthread, kfpu, kernel_fpu_ctx_save, kernel_fpu_ctx_restore,
-             NULL, NULL, NULL, NULL);
- 
          curthread->t_flag |= T_KFPU;
  
          if ((flags & KFPU_USE_LWP) == KFPU_USE_LWP) {
                  /*
                   * For pure kernel threads with an LWP, we can use the LWP's
--- 1386,1395 ----
*** 1418,1427 ****
--- 1408,1427 ----
                  pf->fpu_flags = FPU_EN | FPU_KERNEL;
          } else {
                  /* initialize the kfpu state */
                  kernel_fpu_ctx_restore(kfpu);
          }
+ 
+         /*
+          * Set the context operations for kernel FPU usage. Note that this
+          * cannot be done with pre-emption and interrupts disabled, since
+          * installctx does a sleeping allocation. We haven't finished
+          * initializing our kernel FPU state yet, but in the rare case that we
+          * happen to save/restore before that, no harm is done.
+          */
+         installctx(curthread, kfpu, kernel_fpu_ctx_save, kernel_fpu_ctx_restore,
+             NULL, NULL, NULL, NULL);
  }
  
  void
  kernel_fpu_end(kfpu_state_t *kfpu, uint_t flags)
  {