From: Joerg Roedel <jroe...@suse.de>
The IDT on 64bit contains vectors which use paranoid_entry() and/or IST
stacks. To make these vectors work the TSS and the getcpu GDT entry need
to be set up before the IDT is loaded.
Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
arch/x86/include/asm/processor.h | 1 +
arch/x86/kernel/cpu/common.c | 23 +++++++++++++++++++++++
arch/x86/kernel/smpboot.c | 2 +-
3 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index d8a82e650810..5ac507586769 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -696,6 +696,7 @@ extern void load_direct_gdt(int);
extern void load_fixmap_gdt(int);
extern void load_percpu_segment(int);
extern void cpu_init(void);
+extern void cpu_init_exception_handling(void);
extern void cr4_init(void);
static inline unsigned long get_debugctlmsr(void)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 1d65365363a1..a9527c0c38fb 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1854,6 +1854,29 @@ static inline void tss_setup_io_bitmap(struct tss_struct
*tss)
#endif
}
+/*
+ * Setup everything needed to handle exceptions from the IDT, including the IST
+ * exceptions which use paranoid_entry()
+ */
+void cpu_init_exception_handling(void)
+{
+ struct tss_struct *tss = this_cpu_ptr(&cpu_tss_rw);
+ int cpu = raw_smp_processor_id();
+
+ /* paranoid_entry() gets the CPU number from the GDT */
+ setup_getcpu(cpu);
+
+ /* IST vectors need TSS to be set up. */
+ tss_setup_ist(tss);
+ tss_setup_io_bitmap(tss);
+ set_tss_desc(cpu, &get_cpu_entry_area(cpu)->tss.x86_tss);
+
+ load_TR_desc();
+
+ /* Finally load the IDT */
+ load_current_idt();
+}
+
/*
* cpu_init() initializes state that is per-CPU. Some data is already
* initialized (naturally) in the bootstrap process, such as the GDT
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index f5ef689dd62a..de776b2e6046 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -227,7 +227,7 @@ static void notrace start_secondary(void *unused)
load_cr3(swapper_pg_dir);
__flush_tlb_all();
#endif
- load_current_idt();
+ cpu_init_exception_handling();
cpu_init();
x86_cpuinit.early_percpu_clock_init();
preempt_disable();
--
2.28.0
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