diff options
| author | James Morse <james.morse@arm.com> | 2022-07-14 17:15:23 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2022-07-19 19:27:01 +0100 |
| commit | 44b3834b2eed595af07021b1c64e6f9bc396398b (patch) | |
| tree | 6edd3d5aeff720c50d407985db85f122ca3bd394 /arch/arm64/Kconfig | |
| parent | 39fdb65f52e9a53d32a6ba719f96669fd300ae78 (diff) | |
| download | lwn-44b3834b2eed595af07021b1c64e6f9bc396398b.tar.gz lwn-44b3834b2eed595af07021b1c64e6f9bc396398b.zip | |
arm64: errata: Remove AES hwcap for COMPAT tasks
Cortex-A57 and Cortex-A72 have an erratum where an interrupt that
occurs between a pair of AES instructions in aarch32 mode may corrupt
the ELR. The task will subsequently produce the wrong AES result.
The AES instructions are part of the cryptographic extensions, which are
optional. User-space software will detect the support for these
instructions from the hwcaps. If the platform doesn't support these
instructions a software implementation should be used.
Remove the hwcap bits on affected parts to indicate user-space should
not use the AES instructions.
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: James Morse <james.morse@arm.com>
Link: https://lore.kernel.org/r/20220714161523.279570-3-james.morse@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/Kconfig')
| -rw-r--r-- | arch/arm64/Kconfig | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 0ed35959b090..a42c1e3e7271 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -503,6 +503,22 @@ config ARM64_ERRATUM_834220 If unsure, say Y. +config ARM64_ERRATUM_1742098 + bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence" + depends on COMPAT + default y + help + This option removes the AES hwcap for aarch32 user-space to + workaround erratum 1742098 on Cortex-A57 and Cortex-A72. + + Affected parts may corrupt the AES state if an interrupt is + taken between a pair of AES instructions. These instructions + are only present if the cryptography extensions are present. + All software should have a fallback implementation for CPUs + that don't implement the cryptography extensions. + + If unsure, say Y. + config ARM64_ERRATUM_845719 bool "Cortex-A53: 845719: a load might read incorrect data" depends on COMPAT |