Hi,
On 12/17/20 2:49 AM, Keqian Zhu wrote:
> The parameters start and size are transfered from QEMU memory
> emulation layer. It can promise that they are TARGET_PAGE_SIZE
> aligned. However, KVM needs they are qemu_real_page_size aligned.
>
> Though no caller breaks this aligned requirement currently, we'd
> better add an explicit assert to avoid future breaking.
>
> Signed-off-by: Keqian Zhu <zhukeqi...@huawei.com>
> ---
> accel/kvm/kvm-all.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> ---
> v2
> - Address Andrew's commment (Use assert instead of return err).
>
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index f6b16a8df8..73b195cc41 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -692,6 +692,10 @@ out:
> #define KVM_CLEAR_LOG_ALIGN (qemu_real_host_page_size <<
> KVM_CLEAR_LOG_SHIFT)
> #define KVM_CLEAR_LOG_MASK (-KVM_CLEAR_LOG_ALIGN)
>
> +/*
> + * As the granule of kvm dirty log is qemu_real_host_page_size,
> + * @start and @size are expected and restricted to align to it.
> + */
> static int kvm_log_clear_one_slot(KVMSlot *mem, int as_id, uint64_t start,
> uint64_t size)
> {
> @@ -701,6 +705,9 @@ static int kvm_log_clear_one_slot(KVMSlot *mem, int
> as_id, uint64_t start,
> unsigned long *bmap_clear = NULL, psize = qemu_real_host_page_size;
> int ret;
>
> + /* Make sure start and size are qemu_real_host_page_size aligned */
> + assert(QEMU_IS_ALIGNED(start | size, psize));
Why not return an error instead of aborting the VM?
> /*
> * We need to extend either the start or the size or both to
> * satisfy the KVM interface requirement. Firstly, do the start
>
