summaryrefslogtreecommitdiff
path: root/Documentation/arm64
diff options
context:
space:
mode:
authorCatalin Marinas <catalin.marinas@arm.com>2019-10-28 16:12:40 +0000
committerCatalin Marinas <catalin.marinas@arm.com>2019-10-28 16:12:40 +0000
commit6a036afb5511418995359a9131dbea276758bd10 (patch)
tree704faa6c21fd449ed2117f95775828d68d326a89 /Documentation/arm64
parentba95e9bd963784088709050b72363f57c4861deb (diff)
parent27a22fbdeedd6c5c451cf5f830d51782bf50c3a2 (diff)
Merge branch 'for-next/neoverse-n1-stale-instr' into for-next/core
Neoverse-N1 cores with the 'COHERENT_ICACHE' feature may fetch stale instructions when software depends on prefetch-speculation-protection instead of explicit synchronization. [0] The workaround is to trap I-Cache maintenance and issue an inner-shareable TLBI. The affected cores have a Coherent I-Cache, so the I-Cache maintenance isn't necessary. The core tells user-space it can skip it with CTR_EL0.DIC. We also have to trap this register to hide the bit forcing DIC-aware user-space to perform the maintenance. To avoid trapping all cache-maintenance, this workaround depends on a firmware component that only traps I-cache maintenance from EL0 and performs the workaround. For user-space, the kernel's work is to trap CTR_EL0 to hide DIC, and produce a fake IminLine. EL3 traps the now-necessary I-Cache maintenance and performs the inner-shareable-TLBI that makes everything better. [0] https://developer.arm.com/docs/sden885747/latest/arm-neoverse-n1-mp050-software-developer-errata-notice * for-next/neoverse-n1-stale-instr: arm64: Silence clang warning on mismatched value/register sizes arm64: compat: Workaround Neoverse-N1 #1542419 for compat user-space arm64: Fake the IminLine size on systems affected by Neoverse-N1 #1542419 arm64: errata: Hide CTR_EL0.DIC on systems affected by Neoverse-N1 #1542419
Diffstat (limited to 'Documentation/arm64')
-rw-r--r--Documentation/arm64/silicon-errata.rst2
1 files changed, 2 insertions, 0 deletions
diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index ab7ed2fd072f..f3d2bea25d82 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -88,6 +88,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | Neoverse-N1 | #1349291 | N/A |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | Neoverse-N1 | #1542419 | ARM64_ERRATUM_1542419 |
++----------------+-----------------+-----------------+-----------------------------+
| ARM | MMU-500 | #841119,826419 | N/A |
+----------------+-----------------+-----------------+-----------------------------+
+----------------+-----------------+-----------------+-----------------------------+