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authorAnton Arapov <anton@redhat.com>2012-06-25 18:57:38 +0200
committerAnton Arapov <anton@redhat.com>2012-06-25 18:57:38 +0200
commit3d6fafb8cd68b287130dbd5b19fbb5e9bfa32a54 (patch)
tree72cb222e8096ba95c04460df4de752875b062a23 /drivers/tty/hvc
parent35df99f47c4246df74ed7571c692138b83c3c486 (diff)
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fedora kernel: 6c6f1b8594284404f143c407081ebe65fe068c81v3.4.4-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'drivers/tty/hvc')
-rw-r--r--drivers/tty/hvc/hvc_xen.c31
1 files changed, 17 insertions, 14 deletions
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index d3d91dae065..944eaeb8e0c 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -214,24 +214,24 @@ static int xen_hvm_console_init(void)
/* already configured */
if (info->intf != NULL)
return 0;
-
+ /*
+ * If the toolstack (or the hypervisor) hasn't set these values, the
+ * default value is 0. Even though mfn = 0 and evtchn = 0 are
+ * theoretically correct values, in practice they never are and they
+ * mean that a legacy toolstack hasn't initialized the pv console correctly.
+ */
r = hvm_get_parameter(HVM_PARAM_CONSOLE_EVTCHN, &v);
- if (r < 0) {
- kfree(info);
- return -ENODEV;
- }
+ if (r < 0 || v == 0)
+ goto err;
info->evtchn = v;
- hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &v);
- if (r < 0) {
- kfree(info);
- return -ENODEV;
- }
+ v = 0;
+ r = hvm_get_parameter(HVM_PARAM_CONSOLE_PFN, &v);
+ if (r < 0 || v == 0)
+ goto err;
mfn = v;
info->intf = ioremap(mfn << PAGE_SHIFT, PAGE_SIZE);
- if (info->intf == NULL) {
- kfree(info);
- return -ENODEV;
- }
+ if (info->intf == NULL)
+ goto err;
info->vtermno = HVC_COOKIE;
spin_lock(&xencons_lock);
@@ -239,6 +239,9 @@ static int xen_hvm_console_init(void)
spin_unlock(&xencons_lock);
return 0;
+err:
+ kfree(info);
+ return -ENODEV;
}
static int xen_pv_console_init(void)