Re: [Qemu-devel] [PULL] Fix vhost-net after the MemoryListener trauma

[Anthony Liguori]

On 01/09/2012 08:41 AM, Avi Kivity wrote:
> Please pull from:
>
>    git://git.kernel.org/pub/scm/virt/kvm/qemu-kvm.git
> fix-vhost-after-memory-listener
>
> to fix vhost-net after the MemoryListener changes.  Michael reviewed and
> acked all three patches.
>
> Avi Kivity (3):
>        vhost: fix incorrect userspace address
>        vhost: fix mem_sections memory corruption
>        vhost: improve region filtering
>
>   hw/vhost.c |   23 +++++++++++++++++------
>   1 files changed, 17 insertions(+), 6 deletions(-)

Pulled.  Thanks.

Regards,

Anthony Liguori

> diff --git a/hw/vhost.c b/hw/vhost.c
> index cd56e75..19a7b5c 100644
> --- a/hw/vhost.c
> +++ b/hw/vhost.c
> @@ -15,6 +15,7 @@
>   #include "hw/hw.h"
>   #include "range.h"
>   #include<linux/vhost.h>
> +#include "exec-memory.h"
>
>   static void vhost_dev_sync_region(struct vhost_dev *dev,
>                                     MemoryRegionSection *section,
> @@ -365,10 +366,6 @@ static void vhost_set_memory(MemoryListener *listener,
>       int r;
>       void *ram;
>
> -    if (!memory_region_is_ram(section->mr)) {
> -        return;
> -    }
> -
>       dev->mem = g_realloc(dev->mem, s);
>
>       if (log_dirty) {
> @@ -378,7 +375,7 @@ static void vhost_set_memory(MemoryListener *listener,
>       assert(size);
>
>       /* Optimize no-change case. At least cirrus_vga does this a lot at
> this time. */
> -    ram = memory_region_get_ram_ptr(section->mr);
> +    ram = memory_region_get_ram_ptr(section->mr) +
> section->offset_within_region;
>       if (add) {
>           if (!vhost_dev_cmp_memory(dev, start_addr, size, (uintptr_t)ram)) {
>               /* Region exists with same address. Nothing to do. */
> @@ -430,12 +427,22 @@ static void vhost_set_memory(MemoryListener *listener,
>       }
>   }
>
> +static bool vhost_section(MemoryRegionSection *section)
> +{
> +    return section->address_space == get_system_memory()
> +&&  memory_region_is_ram(section->mr);
> +}
> +
>   static void vhost_region_add(MemoryListener *listener,
>                                MemoryRegionSection *section)
>   {
>       struct vhost_dev *dev = container_of(listener, struct vhost_dev,
>                                            memory_listener);
>
> +    if (!vhost_section(section)) {
> +        return;
> +    }
> +
>       ++dev->n_mem_sections;
>       dev->mem_sections = g_renew(MemoryRegionSection, dev->mem_sections,
>                                   dev->n_mem_sections);
> @@ -450,13 +457,17 @@ static void vhost_region_del(MemoryListener *listener,
>                                            memory_listener);
>       int i;
>
> +    if (!vhost_section(section)) {
> +        return;
> +    }
> +
>       vhost_set_memory(listener, section, false);
>       for (i = 0; i<  dev->n_mem_sections; ++i) {
>           if (dev->mem_sections[i].offset_within_address_space
>               == section->offset_within_address_space) {
>               --dev->n_mem_sections;
>               memmove(&dev->mem_sections[i],&dev->mem_sections[i+1],
> -                    dev->n_mem_sections - i);
> +                    (dev->n_mem_sections - i) *
> sizeof(*dev->mem_sections));
>               break;
>           }
>       }