Re: [PATCH] KVM: PPC: Book3S HV: ptes are big endian

[Alexander Graf <agraf@suse.de>]

On 03.11.14 16:35, Cédric Le Goater wrote:
> When being restored from qemu, the kvm_get_htab_header are in native
> endian, but the ptes are big endian. 
> 
> This patch fixes restore on a KVM LE host. Qemu also needs a fix for
> this :
> 
>      http://lists.nongnu.org/archive/html/qemu-ppc/2014-11/msg00008.html
> 
> Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
> Cc: Gregory Kurz <gkurz@linux.vnet.ibm.com>
> 
> ---
> 
>  Tested on 3.17-rc7 with LE and BE host.
> 
>  
> 
>  arch/powerpc/kvm/book3s_64_mmu_hv.c |    2 ++
>  1 file changed, 2 insertions(+)
> 
> Index: linux-3.18-hv.git/arch/powerpc/kvm/book3s_64_mmu_hv.c
> =================================> --- linux-3.18-hv.git.orig/arch/powerpc/kvm/book3s_64_mmu_hv.c
> +++ linux-3.18-hv.git/arch/powerpc/kvm/book3s_64_mmu_hv.c
> @@ -1542,6 +1542,8 @@ static ssize_t kvm_htab_write(struct fil
>  			err = -EFAULT;
>  			if (__get_user(v, lbuf) || __get_user(r, lbuf + 1))
>  				goto out;
> +			v = be64_to_cpu(v);
> +			r = be64_to_cpu(r);

This will trigger warnings with sparse. Please introduce new be64
variables that you do get_user on and that you then use as source for v
and r.


Alex