Commit 479c2a1c authored by Peter Xu's avatar Peter Xu Committed by Paolo Bonzini
Browse files

ioapic: keep RO bits for IOAPIC entry 



Currently IOAPIC RO bits can be written. To be better aligned with
hardware, we should let them read-only.

Reviewed-by: default avatarRadim Krčmář <rkrcmar@redhat.com>
Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
Message-Id: <1462875682-1349-2-git-send-email-peterx@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 14cb949a

hw/intc/ioapic.c

+4 −0
Original line number Diff line number Diff line
@@ -281,6 +281,7 @@ ioapic_mem_write(void *opaque, hwaddr addr, uint64_t val, 
        default:

            index = (s->ioregsel - IOAPIC_REG_REDTBL_BASE) >> 1;

            if (index >= 0 && index < IOAPIC_NUM_PINS) {

                uint64_t ro_bits = s->ioredtbl[index] & IOAPIC_RO_BITS;

                if (s->ioregsel & 1) {

                    s->ioredtbl[index] &= 0xffffffff;

                    s->ioredtbl[index] |= (uint64_t)val << 32;
@@ -288,6 +289,9 @@ ioapic_mem_write(void *opaque, hwaddr addr, uint64_t val, 
                    s->ioredtbl[index] &= ~0xffffffffULL;

                    s->ioredtbl[index] |= val;

                }

                /* restore RO bits */

                s->ioredtbl[index] &= IOAPIC_RW_BITS;

                s->ioredtbl[index] |= ro_bits;

                ioapic_service(s);

            }

        }

include/hw/i386/ioapic_internal.h

+5 −0
Original line number Diff line number Diff line
@@ -47,6 +47,11 @@ 
#define IOAPIC_LVT_DEST_MODE            (1 << IOAPIC_LVT_DEST_MODE_SHIFT)

#define IOAPIC_LVT_DELIV_MODE           (7 << IOAPIC_LVT_DELIV_MODE_SHIFT)



/* Bits that are read-only for IOAPIC entry */

#define IOAPIC_RO_BITS                  (IOAPIC_LVT_REMOTE_IRR | \

                                         IOAPIC_LVT_DELIV_STATUS)

#define IOAPIC_RW_BITS                  (~(uint64_t)IOAPIC_RO_BITS)



#define IOAPIC_TRIGGER_EDGE             0

#define IOAPIC_TRIGGER_LEVEL            1