Hi!
I didn't get any reply on my previous message, I update patch and I hope I'll
get
reply on that one.
Issue:
KDB early doesn't work. Can't get kdb console during boot.
Investigations:
KDB tries to stop kernel very early (in star_kernel() function) executing
KDB_ENTER().
To stop kernel kdb have to register trap kdb_call() in IDT before KDB_ENTER()
call.
But KDB set gate traps later using initcall.
How Solved:
Patch set KDBENTER_VECTOR trap gate before KDB_ENTER call - in the end of
init_IRQ().
I set KDBENTER_VECTOR trap gate in init_IRQ, not in init_traps(), because in
SMP
case init_IRQ() can reset KDBENTER_VECTOR trap gate to default handler.
I set KDB_VECTOR SMP trap gate in smp_intr_init() - also before KDB_ENTER()
call.
Another issue: kernel can reset KDB trap gates in setup_IO_APIC_irqs(),
so I've added extra check in setup_IO_APIC_irqs() to prevent KDB trap gates
reset.
Patch against krenel 2.6.18. Thanks.
Signed-off-by: Konstantin Baydarov <[EMAIL PROTECTED]>
arch/i386/kdb/kdbasupport.c | 38 --------------------------------------
arch/i386/kernel/i8259.c | 8 ++++++++
arch/i386/kernel/io_apic.c | 5 ++++-
arch/i386/kernel/smpboot.c | 8 ++++++++
arch/i386/kernel/traps.c | 8 ++++++++
5 files changed, 28 insertions(+), 39 deletions(-)
Index: linux-2.6.18/arch/i386/kdb/kdbasupport.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kdb/kdbasupport.c
+++ linux-2.6.18/arch/i386/kdb/kdbasupport.c
@@ -875,32 +875,6 @@ kdba_stackdepth(int argc, const char **a
return 0;
}
-/* Copied from arch/i386/kernel/traps.c */
-
-extern struct desc_struct idt_table[256];
-
-#define _set_gate(gate_addr,type,dpl,addr,seg) \
-do { \
- int __d0, __d1; \
- __asm__ __volatile__ ("movw %%dx,%%ax\n\t" \
- "movw %4,%%dx\n\t" \
- "movl %%eax,%0\n\t" \
- "movl %%edx,%1" \
- :"=m" (*((long *) (gate_addr))), \
- "=m" (*(1+(long *) (gate_addr))), "=&a" (__d0), "=&d" (__d1) \
- :"i" ((short) (0x8000+(dpl<<13)+(type<<8))), \
- "3" ((char *) (addr)),"2" ((seg) << 16)); \
-} while (0)
-
-static void __init set_trap_gate(unsigned int n, void *addr)
-{
- _set_gate(idt_table+n,15,0,addr,__KERNEL_CS);
-}
-
-/* End of copy from arch/i386/kernel/traps.c */
-
-asmlinkage int kdb_call(void);
-
/* Executed once on each cpu at startup. */
void
kdba_cpu_up(void)
@@ -1037,18 +1011,6 @@ kdba_verify_rw(unsigned long addr, size_
return(kdba_getarea_size(data, addr, size) || kdba_putarea_size(addr,
data, size));
}
-static int __init
-kdba_late_init(void)
-{
-#ifdef CONFIG_SMP
- set_intr_gate(KDB_VECTOR, kdb_interrupt);
-#endif
- set_trap_gate(KDBENTER_VECTOR, kdb_call);
- return 0;
-}
-
-__initcall(kdba_late_init);
-
#ifdef CONFIG_SMP
#include <mach_ipi.h>
Index: linux-2.6.18/arch/i386/kernel/i8259.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/i8259.c
+++ linux-2.6.18/arch/i386/kernel/i8259.c
@@ -395,6 +395,11 @@ void __init init_ISA_irqs (void)
}
}
+#ifdef CONFIG_KDB
+asmlinkage int kdb_call(void);
+void __init kdb_set_trap_gate(unsigned int n, void *addr);
+#endif /* CONFIG_KDB */
+
void __init init_IRQ(void)
{
int i;
@@ -434,4 +439,7 @@ void __init init_IRQ(void)
setup_irq(FPU_IRQ, &fpu_irq);
irq_ctx_init(smp_processor_id());
+#ifdef CONFIG_KDB
+ kdb_set_trap_gate(KDBENTER_VECTOR, kdb_call);
+#endif
}
Index: linux-2.6.18/arch/i386/kernel/io_apic.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/io_apic.c
+++ linux-2.6.18/arch/i386/kernel/io_apic.c
@@ -1278,7 +1278,10 @@ static void __init setup_IO_APIC_irqs(vo
if (IO_APIC_IRQ(irq)) {
vector = assign_irq_vector(irq);
entry.vector = vector;
- ioapic_register_intr(irq, vector, IOAPIC_AUTO);
+#ifdef CONFIG_KDB
+ if((vector != KDB_VECTOR) && (vector !=
KDBENTER_VECTOR))
+#endif
+ ioapic_register_intr(irq, vector, IOAPIC_AUTO);
if (!apic && (irq < 16))
disable_8259A_irq(irq);
Index: linux-2.6.18/arch/i386/kernel/smpboot.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/smpboot.c
+++ linux-2.6.18/arch/i386/kernel/smpboot.c
@@ -57,6 +57,11 @@
#include <mach_wakecpu.h>
#include <smpboot_hooks.h>
+#ifdef CONFIG_KDB
+#include <linux/kdb.h>
+#include <linux/kdbprivate.h>
+#endif
+
/* Set if we find a B stepping CPU */
static int __devinitdata smp_b_stepping;
@@ -1485,4 +1490,7 @@ void __init smp_intr_init(void)
/* IPI for generic function call */
set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt);
+#ifdef CONFIG_KDB
+ set_intr_gate(KDB_VECTOR, kdb_interrupt);
+#endif
}
Index: linux-2.6.18/arch/i386/kernel/traps.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/traps.c
+++ linux-2.6.18/arch/i386/kernel/traps.c
@@ -40,6 +40,7 @@
#ifdef CONFIG_KDB
#include <linux/kdb.h>
+#include <linux/kdbprivate.h>
#endif /* CONFIG_KDB */
#include <asm/processor.h>
@@ -1200,6 +1201,13 @@ static void __init set_trap_gate(unsigne
_set_gate(idt_table+n,15,0,addr,__KERNEL_CS);
}
+#ifdef CONFIG_KDB
+void __init kdb_set_trap_gate(unsigned int n, void *addr)
+{
+ set_trap_gate(n, addr);
+}
+#endif
+
static void __init set_system_gate(unsigned int n, void *addr)
{
_set_gate(idt_table+n,15,3,addr,__KERNEL_CS);
---------------------------
Use http://oss.sgi.com/ecartis to modify your settings or to unsubscribe.
