OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

Fix guest OS hang when 64bit PCI bar present

Browse Source 
This patch addresses the issue fully described here:
http://lists.nongnu.org/archive/html/qemu-devel/2013-02/msg01804.html

Linux kernels prior to 2.6.36 do not disable the PCI device during
enumeration process. Since lower and higher parts of a 64bit BAR
are programmed separately this leads to qemu receiving a request to occupy
a completely wrong address region for a short period of time.
We have found that the boot process screws up completely if kvm-apic range
is overlapped even for a short period of time (it is fine for other
regions though).

This patch raises the priority of the kvm-apic memory region, so it is
never pushed out by PCI devices. The patch is quite safe as it does not
touch memory manager.

Signed-off-by: Alexey Korolev <akorolex@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Alexey Korolev 2013-02-22 16:58:44 +13:00 committed by Michael S. Tsirkin
parent 2af234e61d
commit 7feb640cf3
3 changed files with 27 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
hw/sysbus.c
View File

@ -48,7 +48,8 @@ void sysbus_connect_irq(SysBusDevice *dev, int n, qemu_irq irq)
}
}
void sysbus_mmio_map(SysBusDevice *dev, int n, hwaddr addr)
static void sysbus_mmio_map_common(SysBusDevice *dev, int n, hwaddr addr,
bool may_overlap, unsigned priority)
{
assert(n >= 0 && n < dev->num_mmio);
@ -61,11 +62,29 @@ void sysbus_mmio_map(SysBusDevice *dev, int n, hwaddr addr)
memory_region_del_subregion(get_system_memory(), dev->mmio[n].memory);
}
dev->mmio[n].addr = addr;
memory_region_add_subregion(get_system_memory(),
addr,
dev->mmio[n].memory);
if (may_overlap) {
memory_region_add_subregion_overlap(get_system_memory(),
addr,
dev->mmio[n].memory,
priority);
}
else {
memory_region_add_subregion(get_system_memory(),
addr,
dev->mmio[n].memory);
}
}
void sysbus_mmio_map(SysBusDevice *dev, int n, hwaddr addr)
{
sysbus_mmio_map_common(dev, n, addr, false, 0);
}
void sysbus_mmio_map_overlap(SysBusDevice *dev, int n, hwaddr addr,
unsigned priority)
{
sysbus_mmio_map_common(dev, n, addr, true, priority);
}
/* Request an IRQ source. The actual IRQ object may be populated later. */
void sysbus_init_irq(SysBusDevice *dev, qemu_irq *p)

2
hw/sysbus.h
View File

@ -56,6 +56,8 @@ void sysbus_init_ioports(SysBusDevice *dev, pio_addr_t ioport, pio_addr_t size);
void sysbus_connect_irq(SysBusDevice *dev, int n, qemu_irq irq);
void sysbus_mmio_map(SysBusDevice *dev, int n, hwaddr addr);
void sysbus_mmio_map_overlap(SysBusDevice *dev, int n, hwaddr addr,
unsigned priority);
void sysbus_add_memory(SysBusDevice *dev, hwaddr addr,
MemoryRegion *mem);
void sysbus_add_memory_overlap(SysBusDevice *dev, hwaddr addr,

3
target-i386/cpu.c
View File

@ -2088,7 +2088,8 @@ static void x86_cpu_apic_init(X86CPU *cpu, Error **errp)
/* NOTE: the APIC is directly connected to the CPU - it is not
on the global memory bus. */
/* XXX: what if the base changes? */
sysbus_mmio_map(SYS_BUS_DEVICE(env->apic_state), 0, MSI_ADDR_BASE);
sysbus_mmio_map_overlap(SYS_BUS_DEVICE(env->apic_state), 0,
MSI_ADDR_BASE, 0x1000);
apic_mapped = 1;
}
}