kernel/linux.git/arch/arm/kvm/coproc.c, branch linux-4.16.y

KVM: arm: rename pm_fake handler to trap_raz_wi

2017-05-15T12:29:27+00:00

pm_fake doesn't quite describe what the handler does (ignoring writes and returning 0 for reads). As we're about to use it (a lot) in a different context, rename it with a (admitedly cryptic) name that make sense for all users. Signed-off-by: Zhichao Huang Reviewed-by: Alex Bennee Acked-by: Christoffer Dall Acked-by: Marc Zyngier Signed-off-by: Alex Bennée Signed-off-by: Christoffer Dall

KVM: arm: plug potential guest hardware debug leakage

2017-05-15T12:29:19+00:00

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. Cc: stable@vger.kernel.org Signed-off-by: Zhichao Huang Signed-off-by: Alex Bennée Reviewed-by: Christoffer Dall Signed-off-by: Christoffer Dall

ARM: KVM: Fix tracepoint generation after move to virt/kvm/arm/

2017-05-15T06:58:50+00:00

Moving most of the shared code to virt/kvm/arm had for consequence that KVM/ARM doesn't build anymore, because the code that used to define the tracepoints is now somewhere else. Fix this by defining CREATE_TRACE_POINTS in coproc.c, and clean-up trace.h as well. Fixes: 35d2d5d490e2 ("KVM: arm/arm64: Move shared files to virt/kvm/arm") Reported-by: Arnd Bergmann Signed-off-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm: KVM: Treat CP15 accessors returning false as successful

2017-04-09T14:49:17+00:00

Instead of considering that a CP15 accessor has failed when returning false, let's consider that it is *always* successful (after all, we won't stand for an incomplete emulation). The return value now simply indicates whether we should skip the instruction (because it has now been emulated), or if we should leave the PC alone if the emulation has injected an exception. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier

arm: KVM: Make unexpected register accesses inject an undef

2017-04-09T14:49:16+00:00

Reads from write-only system registers are generally confined to EL1 and not propagated to EL2 (that's what the architecture mantates). In order to be sure that we have a sane behaviour even in the unlikely event that we have a broken system, we still handle it in KVM. Same goes for write to RO registers. In that case, let's inject an undef into the guest. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier

ARM: KVM: Support vgic-v3

2016-09-22T11:22:21+00:00

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 Reviewed-by: Christoffer Dall Signed-off-by: Vladimir Murzin Signed-off-by: Christoffer Dall

ARM: KVM: Switch the CP reg search to be a binary search

2016-02-29T18:34:22+00:00

Doing a linear search is a bit silly when we can do a binary search. Not that we trap that so many things that it has become a burden yet, but it makes sense to align it with the arm64 code. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier

ARM: KVM: Rename struct coproc_reg::is_64 to is_64bit

2016-02-29T18:34:22+00:00

As we're going to play some tricks on the struct coproc_reg, make sure its 64bit indicator field matches that of coproc_params. Acked-by: Christoffer Dall Signed-off-by: Marc Zyngier

ARM: KVM: Enforce sorting of all CP tables

2016-02-29T18:34:22+00:00

Since we're obviously terrible at sorting the CP tables, make sure we're going to do it properly (or fail to boot). arm64 has had the same mechanism for a while, and nobody ever broke it... Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier

ARM: KVM: Properly sort the invariant table

2016-02-29T18:34:22+00:00

Not having the invariant table properly sorted is an oddity, and may get in the way of future optimisations. Let's fix it. Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier