diff options
Diffstat (limited to 'hw/virtio/virtio-balloon.c')
| -rw-r--r-- | hw/virtio/virtio-balloon.c | 26 |
1 files changed, 5 insertions, 21 deletions
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c index a78d2d2184..04a7e6c772 100644 --- a/hw/virtio/virtio-balloon.c +++ b/hw/virtio/virtio-balloon.c @@ -117,7 +117,7 @@ static void balloon_deflate_page(VirtIOBalloon *balloon, void *addr = memory_region_get_ram_ptr(mr) + offset; RAMBlock *rb; size_t rb_page_size; - ram_addr_t ram_offset, host_page_base; + ram_addr_t ram_offset; void *host_addr; int ret; @@ -125,27 +125,11 @@ static void balloon_deflate_page(VirtIOBalloon *balloon, * host address? */ rb = qemu_ram_block_from_host(addr, false, &ram_offset); rb_page_size = qemu_ram_pagesize(rb); - host_page_base = ram_offset & ~(rb_page_size - 1); - - if (balloon->pbp - && rb == balloon->pbp->rb - && host_page_base == balloon->pbp->base) { - int subpages = rb_page_size / BALLOON_PAGE_SIZE; - /* - * This means the guest has asked to discard some of the 4kiB - * subpages of a host page, but then changed its mind and - * asked to keep them after all. It's exceedingly unlikely - * for a guest to do this in practice, but handle it anyway, - * since getting it wrong could mean discarding memory the - * guest is still using. */ - clear_bit((ram_offset - balloon->pbp->base) / BALLOON_PAGE_SIZE, - balloon->pbp->bitmap); - - if (bitmap_empty(balloon->pbp->bitmap, subpages)) { - g_free(balloon->pbp); - balloon->pbp = NULL; - } + if (balloon->pbp) { + /* Let's play safe and always reset the pbp on deflation requests. */ + g_free(balloon->pbp); + balloon->pbp = NULL; } host_addr = (void *)((uintptr_t)addr & ~(rb_page_size - 1)); |