[PATCH] parisc: Don't call faulthandler_disabled() in do_page_fault()

[PATCH] parisc: Don't call faulthandler_disabled() in do_page_fault()

[John David Anglin]

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It is dangerous to call faulthandler_disabled() when user_mode(regs)
is true.  The task pagefault_disabled counter is racy and it is not
updated atomically on parisc. As a result, calling faulthandler_disabled()
may cause erroneous termination.

We now handle execption fixups and termination when user_mode(regs) is
false in handle_interruption(). Thus, we can just remove the
faulthandler_disabled() check from do_page_fault().

faulthandler_disabled()

Signed-off-by: John David Anglin <dave.anglin@bell.net>
---

diff --git a/arch/parisc/mm/fault.c b/arch/parisc/mm/fault.c
index 01fd2a32acc6..499e2e8f7f34 100644
--- a/arch/parisc/mm/fault.c
+++ b/arch/parisc/mm/fault.c
@@ -267,9 +267,6 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
 	vm_fault_t fault = 0;
 	unsigned int flags;
 
-	if (faulthandler_disabled())
-		goto no_context;
-
 	tsk = current;
 	mm = tsk->mm;
 	if (!mm)

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