[patch] i386: fix recursive fault in page-fault handler

Chuck Ebbert
2006-07-17T17:25:35Z

Krzysztof Halasa reported recursive faults in do_page_fault()
causing a stream of partial oops messages on the console. Fix
by adding a fixup for that code.

Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>

---

x86_64 looks like it has the same problem.

--- 2.6.18-rc1-32.orig/arch/i386/mm/fault.c
+++ 2.6.18-rc1-32/arch/i386/mm/fault.c
@@ -585,9 +585,20 @@ no_context:
printk(KERN_ALERT "*pte = %08lx\n", page);
}
#endif
- tsk->thread.cr2 = address;
- tsk->thread.trap_no = 14;
- tsk->thread.error_code = error_code;
+ asm ( "# set task data without causing another oops\n"
+ "1:\t"
+ "movl %3,%0\n\t"
+ "movl $14,%1\n\t"
+ "movl %4,%2\n"
+ "2:\n"
+ ".section __ex_table,\"a\"\n\t"
+ ".align 4\n\t"
+ ".long 1b,2b\n"
+ ".previous"
+ : "=m" (tsk->thread.cr2), "=m" (tsk->thread.trap_no),
+ "=m" (tsk->thread.error_code)
+ : "r" (address), "r" (error_code)
+ );
die("Oops", regs, error_code);
bust_spinlocks(0);
do_exit(SIGKILL);
--
And did you exchange a walk-on part in the war for a lead role in a cage?
--Roger Waters