On Wed, Apr 24, 2013 at 3:04 AM, Marc Zyngier <marc.zyngier@xxxxxxx> wrote: > On 23/04/13 23:57, Christoffer Dall wrote: >> On Mon, Apr 08, 2013 at 05:17:09PM +0100, Marc Zyngier wrote: >>> Implement the injection of a fault (undefined, data abort or >>> prefetch abort) into a 64bit guest. >>> >>> Reviewed-by: Christopher Covington <cov@xxxxxxxxxxxxxx> >>> Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> >>> --- >>> arch/arm64/kvm/inject_fault.c | 118 ++++++++++++++++++++++++++++++++++++++++++ >>> 1 file changed, 118 insertions(+) >>> create mode 100644 arch/arm64/kvm/inject_fault.c >>> >>> diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c >>> new file mode 100644 >>> index 0000000..2ff3b78 >>> --- /dev/null >>> +++ b/arch/arm64/kvm/inject_fault.c >>> @@ -0,0 +1,118 @@ >>> +/* >>> + * Fault injection for 64bit guests. >>> + * >>> + * Copyright (C) 2012,2013 - ARM Ltd >>> + * Author: Marc Zyngier <marc.zyngier@xxxxxxx> >>> + * >>> + * Based on arch/arm/kvm/emulate.c >>> + * Copyright (C) 2012 - Virtual Open Systems and Columbia University >>> + * Author: Christoffer Dall <c.dall@xxxxxxxxxxxxxxxxxxxxxx> >>> + * >>> + * This program is free software: you can redistribute it and/or modify >>> + * it under the terms of the GNU General Public License version 2 as >>> + * published by the Free Software Foundation. >>> + * >>> + * This program is distributed in the hope that it will be useful, >>> + * but WITHOUT ANY WARRANTY; without even the implied warranty of >>> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >>> + * GNU General Public License for more details. >>> + * >>> + * You should have received a copy of the GNU General Public License >>> + * along with this program. If not, see <http://www.gnu.org/licenses/>. >>> + */ >>> + >>> +#include <linux/kvm_host.h> >>> +#include <asm/kvm_emulate.h> >>> +#include <asm/esr.h> >>> + >>> +static void inject_abt64(struct kvm_vcpu *vcpu, bool is_iabt, unsigned long addr) >>> +{ >>> + unsigned long cpsr = *vcpu_cpsr(vcpu); >>> + int is_aarch32; >>> + u32 esr = 0; >>> + >>> + is_aarch32 = vcpu_mode_is_32bit(vcpu); >>> + >>> + *vcpu_spsr(vcpu) = cpsr; >>> + *vcpu_elr_el1(vcpu) = *vcpu_pc(vcpu); >>> + >>> + *vcpu_cpsr(vcpu) = PSR_MODE_EL1h | PSR_A_BIT | PSR_F_BIT | PSR_I_BIT; >>> + *vcpu_pc(vcpu) = vcpu_sys_reg(vcpu, VBAR_EL1) + 0x200; >> >> consider a define for the 0x200? > > Yeah, I think Will already mentioned this. > >>> + >>> + vcpu_sys_reg(vcpu, FAR_EL1) = addr; >>> + >>> + /* >>> + * Build an {i,d}abort, depending on the level and the >>> + * instruction set. Report an external synchronous abort. >>> + */ >>> + if (kvm_vcpu_trap_il_is32bit(vcpu)) >>> + esr |= ESR_EL1_IL; >>> + >>> + if (is_aarch32 || (cpsr & PSR_MODE_MASK) == PSR_MODE_EL0t) >>> + esr |= (ESR_EL1_EC_IABT_EL0 << ESR_EL1_EC_SHIFT); >>> + else >>> + esr |= (ESR_EL1_EC_IABT_EL1 << ESR_EL1_EC_SHIFT); >> >> why is it assumed that the abort must come from EL0 if the vcpu is in >> aarch32 mode? > > We're injecting a fault into a VM that runs with a 64bit EL1. So if we > end-up faulting in 32bit code, it must come from EL0. > ah ok, it could be mentioned in a comment, but meh... >>> + >>> + if (!is_iabt) >>> + esr |= ESR_EL1_EC_DABT_EL0; >> >> this is slightly confusing unless you actually look at the definitions >> and realize that or'ing on that extra bit works both in i- and d-abt >> cases. > > Blame Christopher for that, he came up with the idea... ;-) > I think this is one of those cases where the compiler should be this smart, and C should be a little more verbose, but it's not a cardinal point. >>> + >>> + vcpu_sys_reg(vcpu, ESR_EL1) = esr | 0x10; /* External abort */ >>> +} >>> + >>> +static void inject_undef64(struct kvm_vcpu *vcpu) >>> +{ >>> + unsigned long cpsr = *vcpu_cpsr(vcpu); >>> + u32 esr = (ESR_EL1_EC_UNKNOWN << ESR_EL1_EC_SHIFT); >>> + >>> + *vcpu_spsr(vcpu) = cpsr; >>> + *vcpu_elr_el1(vcpu) = *vcpu_pc(vcpu); >>> + >>> + *vcpu_cpsr(vcpu) = PSR_MODE_EL1h | PSR_F_BIT | PSR_I_BIT; >> >> would it make sense to have a define for a common set of these bits or >> is this explicitly defined per exception type in the specs? > > Maybe. Not sure that would be any clearer though... > > M. > -- > Jazz is not dead. It just smells funny... > > > _______________________________________________ > kvmarm mailing list > kvmarm@xxxxxxxxxxxxxxxxxxxxx > https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
