On 10/17/2012 06:49 AM, Konrad Rzeszutek Wilk wrote:
We check the TSS descriptor before we try to dereference it.
Also fix up the value to use the #defines.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com>
---
arch/x86/power/cpu.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index 218cdb1..c17370e 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -133,7 +133,9 @@ static void fix_processor_context(void)
{
int cpu = smp_processor_id();
struct tss_struct *t = &per_cpu(init_tss, cpu);
-
+#ifdef CONFIG_X86_64
+ struct desc_struct *desc = get_cpu_gdt_table(cpu);
+#endif
set_tss_desc(cpu, t); /*
* This just modifies memory; should not be
* necessary. But... This is necessary, because
@@ -142,7 +144,8 @@ static void fix_processor_context(void)
*/
#ifdef CONFIG_X86_64
- get_cpu_gdt_table(cpu)[GDT_ENTRY_TSS].type = 9;
+ if (!desc_empty(&desc[GDT_ENTRY_TSS]))
+ desc[GDT_ENTRY_TSS].type = DESC_TSS;
syscall_init(); /* This sets MSR_*STAR and
related */
#endif
Why is this patch necessary? Presumably there is something further down
the line which depends on the TSS descriptor being empty, but if so, what?
-hpa
--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.
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