linux/arch/arm64
Suzuki K Poulose 1d676673d6 KVM: arm64: Hide system instruction access to Trace registers
Currently we advertise the ID_AA6DFR0_EL1.TRACEVER for the guest,
when the trace register accesses are trapped (CPTR_EL2.TTA == 1).
So, the guest will get an undefined instruction, if trusts the
ID registers and access one of the trace registers.
Lets be nice to the guest and hide the feature to avoid
unexpected behavior.

Even though this can be done at KVM sysreg emulation layer,
we do this by removing the TRACEVER from the sanitised feature
register field. This is fine as long as the ETM drivers
can handle the individual trace units separately, even
when there are differences among the CPUs.

Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210323120647.454211-2-suzuki.poulose@arm.com
2021-03-24 17:26:38 +00:00
..
boot regulator: Updates for v5.12 2021-02-22 09:16:38 -08:00
configs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid 2021-02-23 14:52:22 -08:00
crypto crypto: arm64/crc-t10dif - move NEON yield to C code 2021-02-10 17:55:58 +11:00
include More fixes for ARM and x86. 2021-03-14 12:35:02 -07:00
kernel KVM: arm64: Hide system instruction access to Trace registers 2021-03-24 17:26:38 +00:00
kvm More fixes for ARM and x86. 2021-03-14 12:35:02 -07:00
lib arm64: kasan: simplify and inline MTE functions 2021-02-26 09:41:03 -08:00
mm arm64: mm: use a 48-bit ID map when possible on 52-bit VA builds 2021-03-11 13:04:28 +00:00
net bpf: Rename BPF_XADD and prepare to encode other atomics in .imm 2021-01-14 18:34:29 -08:00
xen
Kbuild
Kconfig arm64/mm: Drop THP conditionality from FORCE_MAX_ZONEORDER 2021-03-08 13:03:54 +00:00
Kconfig.debug arm64: remove TEXT_OFFSET randomization 2020-06-15 13:10:59 +01:00
Kconfig.platforms Updates for the irq subsystem: 2021-02-21 11:53:06 -08:00
Makefile arm64: do not descend to vdso directories twice 2021-01-20 12:18:46 +00:00