Commit Graph

7 Commits

Author SHA1 Message Date
Matt Evans e4fe9e7dc3 kvm: arm64: Fix EC field in inject_abt64
The EC field of the constructed ESR is conditionally modified by ORing in
ESR_ELx_EC_DABT_LOW for a data abort.  However, ESR_ELx_EC_SHIFT is missing
from this condition.

Signed-off-by: Matt Evans <matt.evans@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-05-20 15:39:36 +02:00
Marc Zyngier 8fc153cda9 arm64: KVM: Fix AArch64 guest userspace exception injection
At the moment, our fault injection is pretty limited. We always
generate a SYNC exception into EL1, as if the fault was actually
from EL1h, no matter how it was generated.

This is obviously wrong, as EL0 can generate faults of its own
(not to mention the pretty-much unused EL1t mode).

This patch fixes it by implementing section D1.10.2 of the ARMv8 ARM,
and in particular table D1-7 ("Vector offsets from vector table base
address"), which describes which vector to use depending on the source
exception level and type (synchronous, IRQ, FIQ or SError).

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Tested-by: Shannon Zhao <shannon.zhao@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-01-24 21:55:57 +00:00
Marc Zyngier c0f0963464 arm64: KVM: Fix AArch32 to AArch64 register mapping
When running a 32bit guest under a 64bit hypervisor, the ARMv8
architecture defines a mapping of the 32bit registers in the 64bit
space. This includes banked registers that are being demultiplexed
over the 64bit ones.

On exceptions caused by an operation involving a 32bit register, the
HW exposes the register number in the ESR_EL2 register. It was so
far understood that SW had to distinguish between AArch32 and AArch64
accesses (based on the current AArch32 mode and register number).

It turns out that I misinterpreted the ARM ARM, and the clue is in
D1.20.1: "For some exceptions, the exception syndrome given in the
ESR_ELx identifies one or more register numbers from the issued
instruction that generated the exception. Where the exception is
taken from an Exception level using AArch32 these register numbers
give the AArch64 view of the register."

Which means that the HW is already giving us the translated version,
and that we shouldn't try to interpret it at all (for example, doing
an MMIO operation from the IRQ mode using the LR register leads to
very unexpected behaviours).

The fix is thus not to perform a call to vcpu_reg32() at all from
vcpu_reg(), and use whatever register number is supplied directly.
The only case we need to find out about the mapping is when we
actively generate a register access, which only occurs when injecting
a fault in a guest.

Cc: stable@vger.kernel.org
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-11-24 17:58:08 +01:00
Marc Zyngier 126c69a0bd arm64: KVM: Fix host crash when injecting a fault into a 32bit guest
When injecting a fault into a misbehaving 32bit guest, it seems
rather idiotic to also inject a 64bit fault that is only going
to corrupt the guest state. This leads to a situation where we
perform an illegal exception return at EL2 causing the host
to crash instead of killing the guest.

Just fix the stupid bug that has been there from day 1.

Cc: <stable@vger.kernel.org>
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-08-27 16:16:55 +01:00
Mark Rutland c6d01a947a arm64: kvm: move to ESR_ELx macros
Now that we have common ESR_ELx macros, make use of them in the arm64
KVM code. The addition of <asm/esr.h> to the include path highlighted
badly ordered (i.e. not alphabetical) include lists; these are changed
to alphabetical order.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
2015-01-15 12:24:25 +00:00
Marc Zyngier e82e030556 arm64: KVM: 32bit guest fault injection
Add fault injection capability for 32bit guests.

Reviewed-by: Christopher Covington <cov@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-06-12 16:42:18 +01:00
Marc Zyngier aa8eff9bfb arm64: KVM: fault injection into a guest
Implement the injection of a fault (undefined, data abort or
prefetch abort) into a 64bit guest.

Reviewed-by: Christopher Covington <cov@codeaurora.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2013-06-07 14:03:34 +01:00