__DbgPrintEnable() cannot be called on paging path

The system power up code in XENFILT re-enables DbgPrint hooking.
Unfortunately the undocumented kernel call it uses may require a page-in
and so causes a deadlock when XENVBD is responsible for the page file,
since it depends upon XENFILT to power up.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>

diff --git a/src/xenfilt/fdo.c b/src/xenfilt/fdo.c
index 4736ac7d9caad27adac13374283b52a0c77b845e..1597a15a6c68f58b3ce684dcf40421a3acd62f60 100644 (file)
--- a/src/xenfilt/fdo.c
+++ b/src/xenfilt/fdo.c
@@ -1457,10 +1457,6 @@ FdoSetSystemPowerUp(
           SystemPowerStateName(__FdoGetSystemPowerState(Fdo)),
           SystemPowerStateName(SystemState));
 
-    if (SystemState < PowerSystemHibernate &&
-        __FdoGetSystemPowerState(Fdo) >= PowerSystemHibernate)
-        __DbgPrintEnable();
-
     __FdoSetSystemPowerState(Fdo, SystemState);
 
 done: