ADI is a feature supported on SPARC M7 and newer processors to allow hardware to catch rogue accesses to memory. ADI is supported for data fetches only and not instruction fetches. An app can enable ADI on its data pages, set version tags on them and use versioned addresses to access the data pages. Upper bits of the address contain the version tag. On M7 processors, upper four bits (bits 63-60) contain the version tag. If a rogue app attempts to access ADI enabled data pages, its access is blocked and processor generates an exception. Please see Documentation/sparc/adi.txt for further details.
This patchset implements a char driver to read/write ADI versions from privileged user space processes. Intended consumers are makedumpfile and crash.
v3: * Really fixed the copyright headers to use SPDX GPL v2. Really. v2: * Simplified copyright headers * Completely reworked sparc64 selftests Makefiles. Used the android selftests Makefiles as an example * Added run.sh and drivers_test.sh to the sparc64 selftest directory. Used bpf/test_kmod.sh and the android selftests as examples * Minor cleanups in the selftest adi-test.c * Added calls to ksft_test_*() in the adi-test.c
Tom Hromatka (2): SPARC M7 and newer processors utilize ADI to version and protect memory. This driver is capable of reading/writing ADI/MCD versions from privileged user space processes. Addresses in the adi file are mapped linearly to physical memory at a ratio of 1:adi_blksz. Thus, a read (or write) of offset K in the file operates upon the ADI version at physical address K * adi_blksz. The version information is encoded as one version per byte. Intended consumers are makedumpfile and crash. Add a selftest for the sparc64 privileged ADI driver. These tests verify the read(), pread(), write(), pwrite(), and seek() functionality of the driver. The tests also report simple performance statistics:
drivers/char/Kconfig | 12 + drivers/char/Makefile | 1 + drivers/char/adi.c | 240 +++++++ tools/testing/selftests/Makefile | 1 + tools/testing/selftests/sparc64/Makefile | 46 ++ tools/testing/selftests/sparc64/drivers/.gitignore | 1 + tools/testing/selftests/sparc64/drivers/Makefile | 15 + tools/testing/selftests/sparc64/drivers/adi-test.c | 721 +++++++++++++++++++++ .../selftests/sparc64/drivers/drivers_test.sh | 30 + tools/testing/selftests/sparc64/run.sh | 3 + 10 files changed, 1070 insertions(+) create mode 100644 drivers/char/adi.c create mode 100644 tools/testing/selftests/sparc64/Makefile create mode 100644 tools/testing/selftests/sparc64/drivers/.gitignore create mode 100644 tools/testing/selftests/sparc64/drivers/Makefile create mode 100644 tools/testing/selftests/sparc64/drivers/adi-test.c create mode 100755 tools/testing/selftests/sparc64/drivers/drivers_test.sh create mode 100755 tools/testing/selftests/sparc64/run.sh