diff options
Diffstat (limited to 'arch/i386/kernel/apic.c')
| -rw-r--r-- | arch/i386/kernel/apic.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c index 5f197e197c5..7ce09492fc0 100644 --- a/arch/i386/kernel/apic.c +++ b/arch/i386/kernel/apic.c @@ -157,7 +157,7 @@ void clear_local_APIC(void) maxlvt = get_maxlvt(); /* - * Masking an LVT entry on a P6 can trigger a local APIC error + * Masking an LVT entry can trigger a local APIC error * if the vector is zero. Mask LVTERR first to prevent this. */ if (maxlvt >= 3) { @@ -1118,7 +1118,18 @@ void disable_APIC_timer(void) unsigned long v; v = apic_read(APIC_LVTT); - apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED); + /* + * When an illegal vector value (0-15) is written to an LVT + * entry and delivery mode is Fixed, the APIC may signal an + * illegal vector error, with out regard to whether the mask + * bit is set or whether an interrupt is actually seen on input. + * + * Boot sequence might call this function when the LVTT has + * '0' vector value. So make sure vector field is set to + * valid value. + */ + v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR); + apic_write_around(APIC_LVTT, v); } } |