Re: [Qemu-devel] Fix invalidate if memory requested was not bucket aligned

[Stefano Stabellini]

On Tue, 7 Aug 2012, Frediano Ziglio wrote:
> When memory is mapped in qemu_map_cache with lock != 0 a reverse mapping
> is created pointing to the virtual address of location requested.
> The cached mapped entry is saved in last_address_vaddr with the memory
> location of the base virtual address (without bucket offset).
> However when this entry is invalidated the virtual address saved in the
> reverse mapping is used. This cause that the mapping is freed but the
> last_address_vaddr is not reset.
> 
> Signed-off-by: Frediano Ziglio <address@hidden>

Acked-by: Stefano Stabellini <address@hidden>

I'll add it to my queue.


>  xen-mapcache.c |    9 +++++----
>  1 files changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/xen-mapcache.c b/xen-mapcache.c
> index 59ba085..9cd6db3 100644
> --- a/xen-mapcache.c
> +++ b/xen-mapcache.c
> @@ -320,10 +320,6 @@ void xen_invalidate_map_cache_entry(uint8_t *buffer)
>      target_phys_addr_t size;
>      int found = 0;
>  
> -    if (mapcache->last_address_vaddr == buffer) {
> -        mapcache->last_address_index = -1;
> -    }
> -
>      QTAILQ_FOREACH(reventry, &mapcache->locked_entries, next) {
>          if (reventry->vaddr_req == buffer) {
>              paddr_index = reventry->paddr_index;
> @@ -342,6 +338,11 @@ void xen_invalidate_map_cache_entry(uint8_t *buffer)
>      QTAILQ_REMOVE(&mapcache->locked_entries, reventry, next);
>      g_free(reventry);
>  
> +    if (mapcache->last_address_index == paddr_index) {
> +        mapcache->last_address_index = -1;
> +        mapcache->last_address_vaddr = NULL;
> +    }
> +
>      entry = &mapcache->entry[paddr_index % mapcache->nr_buckets];
>      while (entry && (entry->paddr_index != paddr_index || entry->size != 
> size)) {
>          pentry = entry;
> -- 
> 1.7.5.4
> 
>