From: kaf24@firebug.cl.cam.ac.uk <kaf24@firebug.cl.cam.ac.uk>
Date: Thu, 1 Jun 2006 20:34:47 +0000 (+0100)
Subject: Allow all trace-buffer hypercalls to be executed even when tracing is currently disabled.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~15972^2~49^2~29
X-Git-Url: https://dgit.raspbian.org/%22http://www.example.com/cgi/success//%22http:/www.example.com/cgi/success/?a=commitdiff_plain;h=6af99de37cd929601c69ed3232d4411b8564b8fd;p=xen.git

Allow all trace-buffer hypercalls to be executed even when tracing is currently disabled.
From: George Dunlap
Signed-off-by: Keir Fraser <keir@xensource.com>
---

diff --git a/xen/common/trace.c b/xen/common/trace.c
index 0cee7126d2..6a7827299a 100644
--- a/xen/common/trace.c
+++ b/xen/common/trace.c
@@ -178,20 +178,12 @@ int tb_control(dom0_tbufcontrol_t *tbc)
 
     spin_lock(&lock);
 
-    if ( !tb_init_done &&
-         (tbc->op != DOM0_TBUF_SET_SIZE) &&
-         (tbc->op != DOM0_TBUF_ENABLE) )
-    {
-        spin_unlock(&lock);
-        return -EINVAL;
-    }
-
     switch ( tbc->op )
     {
     case DOM0_TBUF_GET_INFO:
         tbc->cpu_mask   = tb_cpu_mask;
         tbc->evt_mask   = tb_event_mask;
-        tbc->buffer_mfn = __pa(t_bufs[0]) >> PAGE_SHIFT;
+        tbc->buffer_mfn = opt_tbuf_size ? virt_to_mfn(t_bufs[0]) : 0UL;
         tbc->size       = opt_tbuf_size * PAGE_SIZE;
         break;
     case DOM0_TBUF_SET_CPU_MASK: