Re: [Qemu-devel] [PATCH for-2.11] hw/misc/ivshmem: Fix ivshmem_recv_msg() to also work on big endian systems

["Philippe Mathieu-Daudé" <f4bug@amsat.org>]

On 08/30/2017 10:39 AM, Thomas Huth wrote:
> The "slow" ivshmem-tests currently fail when they are running on a
> big endian host:
> 
> $ uname -m
> ppc64
> $ V=1 QTEST_QEMU_BINARY=x86_64-softmmu/qemu-system-x86_64 tests/ivshmem-test -m slow
> /x86_64/ivshmem/single: OK
> /x86_64/ivshmem/hotplug: OK
> /x86_64/ivshmem/memdev: OK
> /x86_64/ivshmem/pair: OK
> /x86_64/ivshmem/server-msi: qemu-system-x86_64:
>   -device ivshmem-doorbell,chardev=chr0,vectors=2: server sent invalid ID message
> Broken pipe
> 
> The problem is that the server side code in ivshmem_server_send_one_msg()
> correctly translates all messages IDs into little endian 64-bit values,
> but the client side code in the ivshmem_recv_msg() function does not swap
> the byte order back. Fix it by passing the value through le64_to_cpu().

Yes, we lack BE testing :(

I read we can run docker on s390x, I wonder if we can ask for a FOSS 
account on some to run the test suite.

> 
> Signed-off-by: Thomas Huth <thuth@redhat.com>

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>

> ---
>   hw/misc/ivshmem.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
> index 47a015f..b3ef3ec 100644
> --- a/hw/misc/ivshmem.c
> +++ b/hw/misc/ivshmem.c
> @@ -653,7 +653,7 @@ static int64_t ivshmem_recv_msg(IVShmemState *s, int *pfd, Error **errp)
>       } while (n < sizeof(msg));
>   
>       *pfd = qemu_chr_fe_get_msgfd(&s->server_chr);
> -    return msg;
> +    return le64_to_cpu(msg);
>   }
>   
>   static void ivshmem_recv_setup(IVShmemState *s, Error **errp)
>