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authorRob Herring <robh@kernel.org>2023-09-21 14:41:52 -0500
committerWill Deacon <will@kernel.org>2023-09-29 16:31:33 +0100
commit471470bc7052d28ce125901877dd10e4c048e513 (patch)
tree37c35c9f68345e85f27589662970da97308f69c6 /Documentation
parenta654a69b9f9c06b2e56387d0b99f0e3e6b0ff4ef (diff)
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>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/arch/arm64/silicon-errata.rst2
1 files changed, 2 insertions, 0 deletions
diff --git a/Documentation/arch/arm64/silicon-errata.rst b/Documentation/arch/arm64/silicon-errata.rst
index e96f057ea2a0..f47f63bcf67c 100644
--- a/Documentation/arch/arm64/silicon-errata.rst
+++ b/Documentation/arch/arm64/silicon-errata.rst
@@ -71,6 +71,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A510 | #2658417 | ARM64_ERRATUM_2658417 |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Cortex-A520 | #2966298 | ARM64_ERRATUM_2966298 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A53 | #826319 | ARM64_ERRATUM_826319 |
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Cortex-A53 | #827319 | ARM64_ERRATUM_827319 |