On Mon, Jul 16, 2018 at 03:43:28PM +0000, Bharat Bhushan wrote: > Hi Christoffer, > > > -----Original Message----- > > From: kvmarm-bounces@xxxxxxxxxxxxxxxxxxxxx [mailto:kvmarm- > > bounces@xxxxxxxxxxxxxxxxxxxxx] On Behalf Of Christoffer Dall > > Sent: Monday, July 16, 2018 6:36 PM > > To: kvmarm@xxxxxxxxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > > Cc: kvm@xxxxxxxxxxxxxxx; Marc Zyngier <marc.zyngier@xxxxxxx>; Andre > > Przywara <andre.przywara@xxxxxxx> > > Subject: [PATCH v4 07/10] KVM: arm/arm64: vgic: Return error on > > incompatible uaccess GICD_IIDR writes > > > > If userspace attempts to write a GICD_IIDR that does not match the > > kernel version, return an error to userspace. The intention is to allow > > implementation changes inside KVM while avoiding silently breaking > > migration resulting in guests not running without any clear indication > > of what went wrong. > > > > Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxx> > > --- > > virt/kvm/arm/vgic/vgic-mmio-v2.c | 21 ++++++++++++++++++--- > > virt/kvm/arm/vgic/vgic-mmio-v3.c | 21 ++++++++++++++++++--- > > 2 files changed, 36 insertions(+), 6 deletions(-) > > > > diff --git a/virt/kvm/arm/vgic/vgic-mmio-v2.c b/virt/kvm/arm/vgic/vgic- > > mmio-v2.c > > index db646f1..4f0f2c4 100644 > > --- a/virt/kvm/arm/vgic/vgic-mmio-v2.c > > +++ b/virt/kvm/arm/vgic/vgic-mmio-v2.c > > @@ -75,6 +75,20 @@ static void vgic_mmio_write_v2_misc(struct kvm_vcpu > > *vcpu, > > } > > } > > > > +static int vgic_mmio_uaccess_write_v2_misc(struct kvm_vcpu *vcpu, > > + gpa_t addr, unsigned int len, > > + unsigned long val) > > +{ > > + switch (addr & 0x0c) { > > I am just understanding the code, not sure if it make sense to replace hardcoded "0x0c". > We could encode it, but we use the hardcoded value elsewhere so I just followed the current pattern. Thanks, -Christoffer
