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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-06-20 16:24:02 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-06-20 16:24:02 -0700
commitff446f2001cf9b5ed97c6256c4ee3549d3b7abed (patch)
treeec5fd60a8b9c21ae85eaa99003f26e6c342e2234 /drivers/tty/hvc/hvc_xen.c
parent78091dc2f6f04b03131218df590c877cadcd9379 (diff)
parent485802a6c524e62b5924849dd727ddbb1497cc71 (diff)
Merge 3.5-rc3 into usb-next
This lets us catch the USB fixes that went into 3.5-rc3 into this branch, as we want them here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/hvc/hvc_xen.c')
-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 d3d91dae065c..944eaeb8e0cf 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)