aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/kvm/hyp/switch.c
Commit message (Collapse)AuthorAge
* KVM: arm: plug potential guest hardware debug leakageZhichao Huang2017-05-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 661e6b02b5aa82db31897f36e96324b77450fd7a upstream. Hardware debugging in guests is not intercepted currently, it means that a malicious guest can bring down the entire machine by writing to the debug registers. This patch enable trapping of all debug registers, preventing the guests to access the debug registers. This includes access to the debug mode(DBGDSCR) in the guest world all the time which could otherwise mess with the host state. Reads return 0 and writes are ignored (RAZ_WI). The result is the guest cannot detect any working hardware based debug support. As debug exceptions are still routed to the guest normal debug using software based breakpoints still works. To support debugging using hardware registers we need to implement a debug register aware world switch as well as special trapping for registers that may affect the host state. Signed-off-by: Zhichao Huang <zhichao.huang@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* ARM: KVM: Support vgic-v3Vladimir Murzin2016-09-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch allows to build and use vgic-v3 in 32-bit mode. Unfortunately, it can not be split in several steps without extra stubs to keep patches independent and bisectable. For instance, virt/kvm/arm/vgic/vgic-v3.c uses function from vgic-v3-sr.c, handling access to GICv3 cpu interface from the guest requires vgic_v3.vgic_sre to be already defined. It is how support has been done: * handle SGI requests from the guest * report configured SRE on access to GICv3 cpu interface from the guest * required vgic-v3 macros are provided via uapi.h * static keys are used to select GIC backend * to make vgic-v3 build KVM_ARM_VGIC_V3 guard is removed along with the static inlines Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* arm: KVM: Preserve pending Virtual Abort in world switchMarc Zyngier2016-09-08
| | | | | | | | | | | | | The HCR.VA bit is used to signal an Abort to a guest, and has the peculiar feature of getting cleared when the guest has taken the abort (this is the only bit that behaves as such in this register). This means that if we signal such an abort, we must leave it in the guest context until it disappears from HCR, and at which point it must be cleared from the context. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* KVM: arm/arm64: Get rid of exported aliases to static functionsChristoffer Dall2016-09-08
| | | | | | | | | | | | | When rewriting the assembly code to C code, it was useful to have exported aliases or static functions so that we could keep the existing common C code unmodified and at the same time rewrite arm64 from assembly to C code, and later do the arm part. Now when both are done, we really don't need this level of indirection anymore, and it's time to save a few lines and brain cells. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
* ARM: KVM: Move kvm/hyp/hyp.h to include/asm/kvm_hyp.hMarc Zyngier2016-02-29
| | | | | | | | | In order to be able to use the code located in virt/kvm/arm/hyp, we need to make the global hyp.h file accessible from include/asm, similar to what we did for arm64. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: KVM: Remove __weak attributesMarc Zyngier2016-02-29
| | | | | | | | Now that the old code is long gone, we can remove all the weak attributes, as there is only one version of the code. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: KVM: Add panic handling codeMarc Zyngier2016-02-29
| | | | | | | | | | Instead of spinning forever, let's "properly" handle any unexpected exception ("properly" meaning "print a spat on the console and die"). This has proved useful quite a few times... Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: KVM: Add populating of fault data structureMarc Zyngier2016-02-29
| | | | | | | | | | On guest exit, we must take care of populating our fault data structure so that the host code can handle it. This includes resolving the IPA for permission faults, which can result in restarting the guest. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* ARM: KVM: Add the new world switch implementationMarc Zyngier2016-02-29
The new world switch implementation is modeled after the arm64 one, calling the various save/restore functions in turn, and having as little state as possible. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>