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Date: Thu, 17 Jul 2003 15:28:19 -0700
From: "Randy.Dunlap" <rddunlap@osdl.org>
To: lkml <linux-kernel@vger.kernel.org>
Subject: asm (lidt) question
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In arch/i386/kernel, inline asm for loading IDT (lidt) is used a few
times, but with slightly different constraints and output/input
definitions.  Are these OK, equivalent, or what?

[rddunlap@dragon kernel]$ findc lidt
./cpu/common.c:484: __asm__ __volatile__("lidt %0": "=m" (idt_descr));
./traps.c:783:	__asm__ __volatile__("lidt %0": "=m" (idt_descr));

vs.

./reboot.c:186:	__asm__ __volatile__ ("lidt %0" : : "m" (real_mode_idt));
./reboot.c:261:	__asm__ __volatile__("lidt %0": :"m" (no_idt));
./suspend.c:95:	asm volatile ("lidt %0" :: "m" (saved_context.idt_limit));


Thanks,
--
~Randy  [yes, i've looked at the inline asm docs]
For Linux-2.6:
http://www.codemonkey.org.uk/post-halloween-2.5.txt
  or http://lwn.net/Articles/39901/
http://www.kernel.org/pub/linux/kernel/people/rusty/modules/