On Wed, 18 Mar 2015 12:25:03 +0100
Paolo Bonzini <pbonz...@redhat.com> wrote:
> From: Greg Kurz <gk...@linux.vnet.ibm.com>
>
> KVM expects host endian values. Hosts that don't use the default endianness
> need to negate the swap performed in adjust_endianness().
>
> Suggested-by: Paolo Bonzini <pbonz...@redhat.com>
> Signed-off-by: Greg Kurz <gk...@linux.vnet.ibm.com>
> Message-Id: <20150313212337.31142.3991.stgit@bahia.local>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
I forgot to Cc qemu-stable@ but I think we really should have this one
in 2.2 to support ppc64le hosts.
--
G
> kvm-all.c | 24 ++++++++++++++++++++++--
> 1 file changed, 22 insertions(+), 2 deletions(-)
>
> diff --git a/kvm-all.c b/kvm-all.c
> index 55025cc..335438a 100644
> --- a/kvm-all.c
> +++ b/kvm-all.c
> @@ -528,13 +528,33 @@ int kvm_vm_check_extension(KVMState *s, unsigned int
> extension)
> return ret;
> }
>
> +static uint32_t adjust_ioeventfd_endianness(uint32_t val, uint32_t size)
> +{
> +#if defined(HOST_WORDS_BIGENDIAN) != defined(TARGET_WORDS_BIGENDIAN)
> + /* The kernel expects ioeventfd values in HOST_WORDS_BIGENDIAN
> + * endianness, but the memory core hands them in target endianness.
> + * For example, PPC is always treated as big-endian even if running
> + * on KVM and on PPC64LE. Correct here.
> + */
> + switch (size) {
> + case 2:
> + val = bswap16(val);
> + break;
> + case 4:
> + val = bswap32(val);
> + break;
> + }
> +#endif
> + return val;
> +}
> +
> static int kvm_set_ioeventfd_mmio(int fd, hwaddr addr, uint32_t val,
> bool assign, uint32_t size, bool datamatch)
> {
> int ret;
> struct kvm_ioeventfd iofd;
>
> - iofd.datamatch = datamatch ? val : 0;
> + iofd.datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0;
> iofd.addr = addr;
> iofd.len = size;
> iofd.flags = 0;
> @@ -564,7 +584,7 @@ static int kvm_set_ioeventfd_pio(int fd, uint16_t addr,
> uint16_t val,
> bool assign, uint32_t size, bool datamatch)
> {
> struct kvm_ioeventfd kick = {
> - .datamatch = datamatch ? val : 0,
> + .datamatch = datamatch ? adjust_ioeventfd_endianness(val, size) : 0,
> .addr = addr,
> .flags = KVM_IOEVENTFD_FLAG_PIO,
> .len = size,
