This series adds a work around for systems with mismatched {I,D}-cache
line sizes. When a thread of execution gets migrated to a different CPU,
the cache line size it had cached could be larger than that of the new
CPU. This could cause data corruption issues. We work around this by
- Dynamically patching the kernel to use the smallest line size on the
system (from the CPU feature infrastructure)
- Trapping the userspace access to CTR_EL0 (by clearing SCTLR_EL1.UCT) and
emulating it with the system wide safe value of CTR.
The series also adds support for alternative code patching of adrp
instructions by adjusting the PC-relative address offset to reflect
the new PC.
The series has been tested on Juno with a hack to forced enabling
of the capability.
Applies on v4.8-rc3. The tree is avaiable at :
git://linux-arm.org/linux-skp.git ctr-v2
Changes since V1:
- Replace adr_adrp insn helper with seperate helpers for adr and adrp.
- Add/use align_down() macro for adjusting the page address for adrp offsets.
- Add comments for existing ISS field defintions.
- Added a patch to disallow silent patching of unhandled pc relative
instructions in alternative code patching.
Suzuki K Poulose (9):
arm64: Set the safe value for L1 icache policy
arm64: Use consistent naming for errata handling
arm64: Rearrange CPU errata workaround checks
arm64: alternative: Disallow patching instructions using literals
arm64: insn: Add helpers for adrp offsets
arm64: alternative: Add support for patching adrp instructions
arm64: Introduce raw_{d,i}cache_line_size
arm64: Refactor sysinstr exception handling
arm64: Work around systems with mismatched cache line sizes
arch/arm64/include/asm/assembler.h | 45 +++++++++++++++++--
arch/arm64/include/asm/cpufeature.h | 14 +++---
arch/arm64/include/asm/esr.h | 84 +++++++++++++++++++++++++++++++----
arch/arm64/include/asm/insn.h | 11 ++++-
arch/arm64/include/asm/sysreg.h | 1 +
arch/arm64/kernel/alternative.c | 21 +++++++++
arch/arm64/kernel/asm-offsets.c | 2 +
arch/arm64/kernel/cpu_errata.c | 26 ++++++++++-
arch/arm64/kernel/cpufeature.c | 44 ++++++++++++++-----
arch/arm64/kernel/cpuinfo.c | 2 -
arch/arm64/kernel/hibernate-asm.S | 2 +-
arch/arm64/kernel/insn.c | 13 ++++++
arch/arm64/kernel/relocate_kernel.S | 2 +-
arch/arm64/kernel/smp.c | 8 +++-
arch/arm64/kernel/traps.c | 87 ++++++++++++++++++++++++++-----------
15 files changed, 297 insertions(+), 65 deletions(-)
--
2.7.4
