Commit d31bf07f authored Mar 18, 2015 by Andy Lutomirski Committed by Ingo Molnar Mar 23, 2015

x86/mm/fault: Use TASK_SIZE_MAX in is_prefetch()

This is slightly shorter and slightly faster.  It's also more
correct: the split between user and kernel addresses is
TASK_SIZE_MAX, regardless of ti->flags.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/09156b63bad90a327827003c9e53faa82ef4c56e.1426728647.git.luto@kernel.org

Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 1daeaa31

arch/x86/mm/fault.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -148,7 +148,7 @@ is_prefetch(struct pt_regs *regs, unsigned long error_code, unsigned long addr)
		instr = (void *)convert_ip_to_linear(current, regs);
		max_instr = instr + 15;

		if (user_mode(regs) && instr >= (unsigned char *)TASK_SIZE)
		if (user_mode(regs) && instr >= (unsigned char *)TASK_SIZE_MAX)
		return 0;

		while (instr < max_instr) {

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