Hi Stefano, On 14/02/17 21:00, Stefano Stabellini wrote:
On Mon, 30 Jan 2017, Andre Przywara wrote:+/* + * Handle incoming LPIs, which are a bit special, because they are potentially + * numerous and also only get injected into guests. Treat them specially here, + * by just looking up their target vCPU and virtual LPI number and hand it + * over to the injection function. + */ +void do_LPI(unsigned int lpi) +{ + struct domain *d; + union host_lpi *hlpip, hlpi; + struct vcpu *vcpu; + + WRITE_SYSREG32(lpi, ICC_EOIR1_EL1); + + hlpip = gic_get_host_lpi(lpi); + if ( !hlpip ) + return; + + hlpi.data = read_u64_atomic(&hlpip->data); + + /* We may have mapped more host LPIs than the guest actually asked for. */ + if ( !hlpi.virt_lpi ) + return; + + d = get_domain_by_id(hlpi.dom_id); + if ( !d ) + return; + + if ( hlpi.vcpu_id >= d->max_vcpus ) + { + put_domain(d); + return; + } + + vcpu = d->vcpu[hlpi.vcpu_id]; + + put_domain(d); + + vgic_vcpu_inject_irq(vcpu, hlpi.virt_lpi);put_domain should be here
Why? I don't even understand why we would need to take a reference on the domain for LPIs. Would not it be enough to use rcu_lock_domain_by_id here?
Regards, -- Julien Grall _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel
