Since Armv9.6, FEAT_LSUI supplies the load/store instructions for previleged level to access to access user memory without clearing PSTATE.PAN bit.
This patchset support FEAT_LSUI and applies it mainly in futex atomic operation and others. This patch based on v7.0-rc1 Patch History ============== form v12 to v13: - rebase to v7.0-rc1 - apply CASLT for swapping guest descriptor - remove has_lsui() for checking cpu feature. - simplify __lsui_cmpxchg32() according to @Catalin's suggestion. - use uaccess_ttbr0_enable()/disable() for LSUI instructions. - https://lore.kernel.org/all/[email protected]/ from v11 to v12: - rebase to v6.19-rc6 - add CONFIG_ARM64_LSUI - enable LSUI when !CPU_BIG_ENDIAN and PAN presents. - drop the swp emulation with LSUI insns instead, disable it when LSUI presents. - some of small fixes (useless prefix and suffix and etc). - https://lore.kernel.org/all/[email protected]/ from v10 to v11: - rebase to v6.19-rc1 - use cast instruction to emulate deprecated swpb instruction - https://lore.kernel.org/all/[email protected]/ from v9 to v10: - apply FEAT_LSUI to user_swpX emulation. - add test coverage for LSUI bit in ID_AA64ISAR3_EL1 - rebase to v6.18-rc4 - https://lore.kernel.org/all/[email protected]/ from v8 to v9: - refotoring __lsui_cmpxchg64() - rebase to v6.17-rc7 - https://lore.kernel.org/all/[email protected]/ from v7 to v8: - implements futex_atomic_eor() and futex_atomic_cmpxchg() with casalt with C helper. - Drop the small optimisation on ll/sc futex_atomic_set operation. - modify some commit message. - https://lore.kernel.org/all/[email protected]/ from v6 to v7: - wrap FEAT_LSUI with CONFIG_AS_HAS_LSUI in cpufeature - remove unnecessary addition of indentation. - remove unnecessary mte_tco_enable()/disable() on LSUI operation. - https://lore.kernel.org/all/[email protected]/ from v5 to v6: - rebase to v6.17-rc1 - https://lore.kernel.org/all/[email protected]/ from v4 to v5: - remove futex_ll_sc.h futext_lsui and lsui.h and move them to futex.h - reorganize the patches. - https://lore.kernel.org/all/[email protected]/ from v3 to v4: - rebase to v6.16-rc7 - modify some patch's title. - https://lore.kernel.org/all/[email protected]/ from v2 to v3: - expose FEAT_LSUI to guest - add help section for LSUI Kconfig - https://lore.kernel.org/all/[email protected]/ from v1 to v2: - remove empty v9.6 menu entry - locate HAS_LSUI in cpucaps in order - https://lore.kernel.org/all/[email protected]/ Yeoreum Yun (8): arm64: cpufeature: add FEAT_LSUI KVM: arm64: expose FEAT_LSUI to guest KVM: arm64: kselftest: set_id_regs: add test for FEAT_LSUI arm64: futex: refactor futex atomic operation arm64: futex: support futex with FEAT_LSUI arm64: armv8_deprecated: disable swp emulation when FEAT_LSUI present KVM: arm64: use CASLT instruction for swapping guest descriptor arm64: Kconfig: add support for LSUI arch/arm64/Kconfig | 20 ++ arch/arm64/include/asm/futex.h | 284 +++++++++++++++--- arch/arm64/include/asm/lsui.h | 27 ++ arch/arm64/kernel/armv8_deprecated.c | 16 + arch/arm64/kernel/cpufeature.c | 10 + arch/arm64/kvm/at.c | 32 +- arch/arm64/kvm/sys_regs.c | 3 +- arch/arm64/tools/cpucaps | 1 + .../testing/selftests/kvm/arm64/set_id_regs.c | 1 + 9 files changed, 342 insertions(+), 52 deletions(-) create mode 100644 arch/arm64/include/asm/lsui.h -- LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}
