linux/arch/arm64
Rob Herring 471470bc70 arm64: errata: Add Cortex-A520 speculative unprivileged load workaround
Implement the workaround for ARM Cortex-A520 erratum 2966298. On an
affected Cortex-A520 core, a speculatively executed unprivileged load
might leak data from a privileged load via a cache side channel. The
issue only exists for loads within a translation regime with the same
translation (e.g. same ASID and VMID). Therefore, the issue only affects
the return to EL0.

The workaround is to execute a TLBI before returning to EL0 after all
loads of privileged data. A non-shareable TLBI to any address is
sufficient.

The workaround isn't necessary if page table isolation (KPTI) is
enabled, but for simplicity it will be. Page table isolation should
normally be disabled for Cortex-A520 as it supports the CSV3 feature
and the E0PD feature (used when KASLR is enabled).

Cc: stable@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230921194156.1050055-2-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-09-29 16:31:33 +01:00
..
boot Char/Misc driver changes for 6.6-rc1 2023-09-01 09:53:54 -07:00
configs Kbuild updates for v6.6 2023-09-05 11:01:47 -07:00
crypto crypto: arm64/aes - remove Makefile hack 2023-08-11 19:19:27 +08:00
hyperv arm64/hyperv: Use CPUHP_AP_HYPERV_ONLINE state to fix CPU online sequencing 2023-06-17 23:09:47 +00:00
include arm64: Add Cortex-A520 CPU part definition 2023-09-29 16:31:32 +01:00
kernel arm64: errata: Add Cortex-A520 speculative unprivileged load workaround 2023-09-29 16:31:33 +01:00
kvm ARM: 2023-09-07 13:52:20 -07:00
lib arm64 fixes for -rc1 2023-09-08 12:48:37 -07:00
mm Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
net bpf, arm64: Support signed div/mod instructions 2023-08-18 15:46:35 +02:00
tools arm64: errata: Add Cortex-A520 speculative unprivileged load workaround 2023-09-29 16:31:33 +01:00
xen
Kbuild
Kconfig arm64: errata: Add Cortex-A520 speculative unprivileged load workaround 2023-09-29 16:31:33 +01:00
Kconfig.debug
Kconfig.platforms STM32 STM32MP25 for v6.5, round 1 2023-06-20 22:28:44 +02:00
Makefile