[IA64] page_not_present fault in region 5 is normal
When copying data from user-space to kernel-space by __copy_user(),
a page_not_present fault sometimes occurs at vmalloced kernel address
because of VHPT pre-fetching.
Ignore the page_not_present fault in ia64_do_page_fault() before
jumping into exception handlers.
Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c
index ff62551..839d4f1 100644
--- a/arch/ia64/mm/fault.c
+++ b/arch/ia64/mm/fault.c
@@ -229,9 +229,6 @@
return;
}
- if (ia64_done_with_exception(regs))
- return;
-
/*
* Since we have no vma's for region 5, we might get here even if the address is
* valid, due to the VHPT walker inserting a non present translation that becomes
@@ -242,6 +239,9 @@
if (REGION_NUMBER(address) == 5 && mapped_kernel_page_is_present(address))
return;
+ if (ia64_done_with_exception(regs))
+ return;
+
/*
* Oops. The kernel tried to access some bad page. We'll have to terminate things
* with extreme prejudice.