Re: [Qemu-devel] [PULL 43/46] block: Assertions for write permissions

[Richard W.M. Jones]

On Tue, Feb 28, 2017 at 09:36:42PM +0100, Kevin Wolf wrote:
> This adds assertions that ensure that the necessary write permissions
> have been granted before someone attempts to write to a node.
> 
> Signed-off-by: Kevin Wolf <address@hidden>
> Acked-by: Fam Zheng <address@hidden>
> Reviewed-by: Max Reitz <address@hidden>
> ---
>  block/io.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/block/io.c b/block/io.c
> index 2592ca1..4c79745 100644
> --- a/block/io.c
> +++ b/block/io.c
> @@ -945,6 +945,8 @@ static int coroutine_fn 
> bdrv_co_do_copy_on_readv(BdrvChild *child,
>      size_t skip_bytes;
>      int ret;
>  
> +    assert(child->perm & (BLK_PERM_WRITE_UNCHANGED | BLK_PERM_WRITE));


This assertion is thrown in the libguestfs test suite.  I filed a bug
about it against the Fedora package:

https://lists.gnu.org/archive/html/qemu-block/2017-02/msg01305.html

Rich.

-- 
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