[Xen-devel] question about patch 13252

To:	"jbeulich@xxxxxxxxxx" <jbeulich@xxxxxxxxxx>
Subject:	[Xen-devel] question about patch 13252
From:	"Lu, Guanqun" <guanqun.lu@xxxxxxxxx>
Date:	Thu, 19 Mar 2009 22:07:51 +0800
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Thread-topic:	question about patch 13252

Hi Jan,

I saw that in patch 13252,
you added such lines in xen/arch/x86/traps.c

+#ifdef CONFIG_COMPAT
+    _set_tssldt_desc(
+        compat_gdt_table + __TSS(n) - FIRST_RESERVED_GDT_ENTRY,
+        (unsigned long)addr,
+        offsetof(struct tss_struct, __cacheline_filler) - 1,
+        11);
+#endif

I have such question about the number 11, 11 is 1010 in binary format,
which means that the busy flat is set.  Then later, load_TR() is called.
load_TR() is a wrapper around instruction 'ltr'.  As I consult SDM2A,
it says that ltr will generate #GP, when the busy flag is set.

So I'm a little puzzled. Can you explain a little why it's not 9 ?
Or am I missing something here?

Thanks.

--
Guanqun

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[Xen-devel] question about patch 13252