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([2804:7f0:b403:720f:3e7c:3fff:fe7a:e83b]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-710cb22a455sm373484b3a.71.2024.08.07.22.15.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Aug 2024 22:16:00 -0700 (PDT) From: Gustavo Romero To: qemu-devel@nongnu.org, alex.bennee@linaro.org, richard.henderson@linaro.org Cc: philmd@linaro.org, peter.maydell@linaro.org, gustavo.romero@linaro.org Subject: [PATCH v2 4/4] tests/tcg/aarch64: Extend MTE gdbstub tests to system mode Date: Thu, 8 Aug 2024 05:15:31 +0000 Message-Id: <20240808051531.3183498-5-gustavo.romero@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240808051531.3183498-1-gustavo.romero@linaro.org> References: <20240808051531.3183498-1-gustavo.romero@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::136; envelope-from=gustavo.romero@linaro.org; helo=mail-il1-x136.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Extend MTE gdbstub tests to also run in system mode (share tests between user mode and system mode). The tests will only run if a version of GDB that supports MTE on baremetal is available in the test environment and if available compiler supports the 'memtag' flag (-march=armv8.5-a+memtag). For the tests running in system mode, a page that supports MTE ops. is necessary. Therefore, an MTE-enabled page is made available (mapped) in the third 2 MB chunk of the second 1 GB space in the flat mapping set in boot.S. A new binary, mte.S, is also introduced for the tests. It links against boot.S and is executed by QEMU in system mode. Signed-off-by: Gustavo Romero --- configure | 5 + tests/tcg/aarch64/Makefile.softmmu-target | 49 ++++++++- tests/tcg/aarch64/Makefile.target | 3 +- tests/tcg/aarch64/gdbstub/test-mte.py | 71 ++++++++----- tests/tcg/aarch64/system/boot.S | 14 +++ tests/tcg/aarch64/system/kernel.ld | 5 + tests/tcg/aarch64/system/mte.S | 115 ++++++++++++++++++++++ 7 files changed, 234 insertions(+), 28 deletions(-) create mode 100644 tests/tcg/aarch64/system/mte.S diff --git a/configure b/configure index d08b71f14b..40186d865e 100755 --- a/configure +++ b/configure @@ -1679,6 +1679,11 @@ for target in $target_list; do echo "GDB_HAS_MTE=y" >> $config_target_mak fi + if test "${gdb_arches#*aarch64}" != "$gdb_arches" && version_ge $gdb_version 16.0; then + # GDB has to support MTE in baremetal to allow debugging MTE in QEMU system mode + echo "GDB_SUPPORTS_MTE_IN_BAREMETAL=y" >> $config_target_mak + fi + echo "run-tcg-tests-$target: $qemu\$(EXESUF)" >> Makefile.prereqs tcg_tests_targets="$tcg_tests_targets $target" fi diff --git a/tests/tcg/aarch64/Makefile.softmmu-target b/tests/tcg/aarch64/Makefile.softmmu-target index 139e04d15f..59ee662cda 100644 --- a/tests/tcg/aarch64/Makefile.softmmu-target +++ b/tests/tcg/aarch64/Makefile.softmmu-target @@ -2,14 +2,22 @@ # Aarch64 system tests # -AARCH64_SYSTEM_SRC=$(SRC_PATH)/tests/tcg/aarch64/system +AARCH64_SRC=$(SRC_PATH)/tests/tcg/aarch64 +AARCH64_SYSTEM_SRC=$(AARCH64_SRC)/system + VPATH+=$(AARCH64_SYSTEM_SRC) # These objects provide the basic boot code and helper functions for all tests CRT_OBJS=boot.o -AARCH64_TEST_SRCS=$(wildcard $(AARCH64_SYSTEM_SRC)/*.c) -AARCH64_TESTS = $(patsubst $(AARCH64_SYSTEM_SRC)/%.c, %, $(AARCH64_TEST_SRCS)) +AARCH64_TEST_C_SRCS_=$(wildcard $(AARCH64_SYSTEM_SRC)/*.c) +AARCH64_TEST_S_SRCS=$(AARCH64_SYSTEM_SRC)/mte.S + +AARCH64_C_TESTS = $(patsubst $(AARCH64_SYSTEM_SRC)/%.c, %, $(AARCH64_TEST_C_SRCS)) +AARCH64_S_TESTS = $(patsubst $(AARCH64_SYSTEM_SRC)/%.S, %, $(AARCH64_TEST_S_SRCS)) + +AARCH64_TESTS = $(AARCH64_C_TESTS) +AARCH64_TESTS += $(AARCH64_S_TESTS) CRT_PATH=$(AARCH64_SYSTEM_SRC) LINK_SCRIPT=$(AARCH64_SYSTEM_SRC)/kernel.ld @@ -21,7 +29,8 @@ LDFLAGS+=-static -nostdlib $(CRT_OBJS) $(MINILIB_OBJS) -lgcc config-cc.mak: Makefile $(quiet-@)( \ - $(call cc-option,-march=armv8.3-a, CROSS_CC_HAS_ARMV8_3)) 3> config-cc.mak + $(call cc-option,-march=armv8.3-a, CROSS_CC_HAS_ARMV8_3); \ + $(call cc-option,-march=armv8.5-a+memtag, CROSS_CC_HAS_ARMV8_MTE)) 3> config-cc.mak -include config-cc.mak # building head blobs @@ -88,3 +97,35 @@ pauth-3: run-pauth-3: $(call skip-test, "RUN of pauth-3", "not built") endif + +ifneq ($(CROSS_CC_HAS_ARMV8_MTE),) +QEMU_MTE_ENABLED_MACHINE=-M virt,mte=on -cpu max -display none +QEMU_OPTS_WITH_MTE_ON = $(QEMU_MTE_ENABLED_MACHINE) $(QEMU_BASE_ARGS) -kernel +mte: CFLAGS+=-march=armv8.5-a+memtag +mte: mte.S $(LINK_SCRIPT) $(CRT_OBJS) $(MINILIB_OBJS) + $(CC) $(CFLAGS) $(EXTRA_CFLAGS) $< -o $@ $(LDFLAGS) + +run-mte: QEMU_OPTS=$(QEMU_OPTS_WITH_MTE_ON) +run-mte: mte + +ifeq ($(GDB_SUPPORTS_MTE_IN_BAREMETAL),y) +run-gdbstub-mte: QEMU_OPTS=$(QEMU_OPTS_WITH_MTE_ON) +run-gdbstub-mte: mte + $(call run-test, $@, $(GDB_SCRIPT) \ + --output run-gdbstub-mte.out \ + --gdb $(GDB) \ + --qemu $(QEMU) --qargs "-chardev null$(COMMA)id=output $(QEMU_OPTS)" \ + --bin $< --test $(AARCH64_SRC)/gdbstub/test-mte.py -- --mode=system, \ + gdbstub MTE support) + +EXTRA_RUNS += run-gdbstub-mte +else # !GDB_SUPPORTS_MTE_IN_BAREMETAL +run-gdbstub-mte: + $(call skip-test "RUN of gdbstub-mte", "GDB does not support MTE in baremetal!") +endif +else # !CROSS_CC_HAS_ARMV8_MTE +mte: + $(call skip-test, "BUILD of $@", "missing compiler support") +run-mte: + $(call skip-test, "RUN of mte", "not build") +endif diff --git a/tests/tcg/aarch64/Makefile.target b/tests/tcg/aarch64/Makefile.target index 8cc62eb456..9efe2f81ad 100644 --- a/tests/tcg/aarch64/Makefile.target +++ b/tests/tcg/aarch64/Makefile.target @@ -138,7 +138,8 @@ run-gdbstub-mte: mte-8 $(call run-test, $@, $(GDB_SCRIPT) \ --gdb $(GDB) \ --qemu $(QEMU) --qargs "$(QEMU_OPTS)" \ - --bin $< --test $(AARCH64_SRC)/gdbstub/test-mte.py, \ + --bin $< --test $(AARCH64_SRC)/gdbstub/test-mte.py \ + -- --mode=user, \ gdbstub MTE support) EXTRA_RUNS += run-gdbstub-mte diff --git a/tests/tcg/aarch64/gdbstub/test-mte.py b/tests/tcg/aarch64/gdbstub/test-mte.py index 66f9c25f8a..a4cae6caa0 100644 --- a/tests/tcg/aarch64/gdbstub/test-mte.py +++ b/tests/tcg/aarch64/gdbstub/test-mte.py @@ -1,21 +1,26 @@ from __future__ import print_function # # Test GDB memory-tag commands that exercise the stubs for the qIsAddressTagged, -# qMemTag, and QMemTag packets. Logical tag-only commands rely on local -# operations, hence don't exercise any stub. +# qMemTag, and QMemTag packets, which are used for manipulating allocation tags. +# Logical tags-related commands rely on local operations, hence don't exercise +# any stub and so are not used in this test. # -# The test consists in breaking just after a atag() call (which sets the -# allocation tag -- see mte-8.c for details) and setting/getting tags in -# different memory locations and ranges starting at the address of the array -# 'a'. +# The test consists in breaking just after a tag is set in a specific memory +# chunk, and then using the GDB 'memory-tagging' subcommands to set/get tags in +# different memory locations and ranges in the MTE-enabled memory chunk. # # This is launched via tests/guest-debug/run-test.py # -import gdb +try: + import gdb +except ModuleNotFoundError: + from sys import exit + exit("This script must be launched via tests/guest-debug/run-test.py!") import re -from test_gdbstub import main, report +from sys import argv +from test_gdbstub import arg_parser, main, report PATTERN_0 = "Memory tags for address 0x[0-9a-f]+ match \\(0x[0-9a-f]+\\)." @@ -23,12 +28,32 @@ def run_test(): - gdb.execute("break 95", False, True) + p = arg_parser(prog="test-mte.py", description="TCG MTE tests.") + p.add_argument("--mode", help="Run test for QEMU system or user mode.", + required=True, choices=['system','user']) + + args = p.parse_args(args=argv) + + if args.mode == "system": + # Break address: where to break before performing the tests + # See mte.S for details about this label. + ba = "main_end" + # Tagged address: the start of the MTE-enabled memory chunk to be tested + # 'tagged_addr' (x1) is a pointer to the MTE-enabled page. See mte.S. + ta = "$x1" + else: # mode="user" + # Line 95 in mte-8.c + ba = "95" + # 'a' array. See mte-8.c + ta = "a" + + gdb.execute(f"break {ba}", False, True) gdb.execute("continue", False, True) + try: - # Test if we can check correctly that the allocation tag for - # array 'a' matches the logical tag after atag() is called. - co = gdb.execute("memory-tag check a", False, True) + # Test if we can check correctly that the allocation tag for the address + # in {ta} matches the logical tag in {ta}. + co = gdb.execute(f"memory-tag check {ta}", False, True) tags_match = re.findall(PATTERN_0, co, re.MULTILINE) if tags_match: report(True, f"{tags_match[0]}") @@ -39,20 +64,20 @@ def run_test(): # tags rely on local operation and so don't exercise any stub. # Set the allocation tag for the first granule (16 bytes) of - # address starting at 'a' address to a known value, i.e. 0x04. - gdb.execute("memory-tag set-allocation-tag a 1 04", False, True) + # address starting at {ta} address to a known value, i.e. 0x04. + gdb.execute(f"memory-tag set-allocation-tag {ta} 1 04", False, True) # Then set the allocation tag for the second granule to a known # value, i.e. 0x06. This tests that contiguous tag granules are - # set correct and don't run over each other. - gdb.execute("memory-tag set-allocation-tag a+16 1 06", False, True) + # set correctly and don't run over each other. + gdb.execute(f"memory-tag set-allocation-tag {ta}+16 1 06", False, True) # Read the known values back and check if they remain the same. - co = gdb.execute("memory-tag print-allocation-tag a", False, True) + co = gdb.execute(f"memory-tag print-allocation-tag {ta}", False, True) first_tag = re.match(PATTERN_1, co)[1] - co = gdb.execute("memory-tag print-allocation-tag a+16", False, True) + co = gdb.execute(f"memory-tag print-allocation-tag {ta}+16", False, True) second_tag = re.match(PATTERN_1, co)[1] if first_tag == "0x4" and second_tag == "0x6": @@ -61,15 +86,15 @@ def run_test(): report(False, "Can't set/print allocation tags!") # Now test fill pattern by setting a whole page with a pattern. - gdb.execute("memory-tag set-allocation-tag a 4096 0a0b", False, True) + gdb.execute(f"memory-tag set-allocation-tag {ta} 4096 0a0b", False, True) # And read back the tags of the last two granules in page so # we also test if the pattern is set correctly up to the end of # the page. - co = gdb.execute("memory-tag print-allocation-tag a+4096-32", False, True) + co = gdb.execute(f"memory-tag print-allocation-tag {ta}+4096-32", False, True) tag = re.match(PATTERN_1, co)[1] - co = gdb.execute("memory-tag print-allocation-tag a+4096-16", False, True) + co = gdb.execute(f"memory-tag print-allocation-tag {ta}+4096-16", False, True) last_tag = re.match(PATTERN_1, co)[1] if tag == "0xa" and last_tag == "0xb": @@ -78,8 +103,8 @@ def run_test(): report(False, "Fill pattern failed!") except gdb.error: - # This usually happens because a GDB version that does not - # support memory tagging was used to run the test. + # This usually happens because a GDB version that does not support + # memory tagging was used to run the test. report(False, "'memory-tag' command failed!") diff --git a/tests/tcg/aarch64/system/boot.S b/tests/tcg/aarch64/system/boot.S index 501685d0ec..79a2ada74a 100644 --- a/tests/tcg/aarch64/system/boot.S +++ b/tests/tcg/aarch64/system/boot.S @@ -135,6 +135,17 @@ __start: orr x1, x1, x3 str x1, [x2] /* 2nd 2mb (.data & .bss)*/ + /* Third block: .mte_page */ + adrp x1, .mte_page + add x1, x1, :lo12:.mte_page + bic x1, x1, #(1 << 21) - 1 + and x4, x1, x5 + add x2, x0, x4, lsr #(21 - 3) + /* attr(AF, NX, block, AttrIndx=Attr1) */ + ldr x3, =(3 << 53) | 0x401 | (1 << 2) + orr x1, x1, x3 + str x1, [x2] + /* Setup/enable the MMU. */ /* @@ -239,3 +250,6 @@ ttb_stage2: stack: .space 65536, 0 stack_end: + + /* .mte_page location is set in kernel.ld. */ + .section .mte_page diff --git a/tests/tcg/aarch64/system/kernel.ld b/tests/tcg/aarch64/system/kernel.ld index 7b3a76dcbf..7c00c1c378 100644 --- a/tests/tcg/aarch64/system/kernel.ld +++ b/tests/tcg/aarch64/system/kernel.ld @@ -18,6 +18,11 @@ SECTIONS .bss : { *(.bss) } + /* align MTE section to next (third) 2mb */ + . = ALIGN(1 << 22); + .mte : { + *(.mte_page) + } /DISCARD/ : { *(.ARM.attributes) } diff --git a/tests/tcg/aarch64/system/mte.S b/tests/tcg/aarch64/system/mte.S new file mode 100644 index 0000000000..e916ed53b4 --- /dev/null +++ b/tests/tcg/aarch64/system/mte.S @@ -0,0 +1,115 @@ +/* + * Code to help test the MTE gdbstubs in system mode. + * + * Copyright (c) 2024 Linaro Limited + * + * Author: Gustavo Romero + * + * SPDX-License-Identifier: LGPL-2.1-or-later + */ + +#define addr x0 /* Ptr to the start of the MTE-enabled page. */ +#define tagged_addr x1 /* 'addr' ptr with a random-generated tag added. */ +#define tmp0 x2 /* Scratch register. */ +#define tmp1 x3 /* Scratch register. */ +#define tmp2 x4 /* Scratch register. */ +#define tmp3 x5 /* Sctatch register. */ + + .file "mte.S" + + .text + .align 4 + + .globl main + .type main, @function + +main: + /* + * Set MAIR_EL1 (Memory Attribute Index Register). In boot.S, the + * attribute index for .mte_page is set to point to MAILR_EL field Attr1 + * (AttrIndx=Attr1), so set Attr1 as Tagged Normal (MTE) to enable MTE + * on this page. + * + * Attr1 = 0xF0 => Tagged Normal (MTE) + */ + mrs tmp0, mair_el1 + orr tmp0, tmp0, (0xF0 << 8) + msr mair_el1, tmp0 + + /* + * Set TCR_EL1 (Translation Control Registers) to ignore the top byte + * in the translated addresses so it can be used to keep the tags. + * + * TBI0[37] = 0b1 => Top Byte ignored and used for tagged addresses + */ + mrs tmp1, tcr_el1 + orr tmp1, tmp1, (1 << 37) + msr tcr_el1, tmp1 + + /* + * Set SCTLR_EL1 (System Control Register) to enable the use of MTE + * insns., like stg & friends, and to enable synchronous exception in + * case of a tag mismatch, i.e., when the logical tag in 'tagged_addr' + * is different from the allocation tag related to 'addr' address. + * + * ATA[43] = 0b1 => Enable access to allocation tags at EL1 + * TCF[41:40] = 0b01 => Tag Check Faults cause a synchronous exception + * + */ + mrs tmp2, sctlr_el1 + mov tmp3, (1 << 43) | (1 << 40) + orr tmp2, tmp2, tmp3 + msr sctlr_el1, tmp2 + + isb + + /* + * MTE-enabled page resides at the 3rd 2MB chunk in the second 1GB + * block, i.e., at 0x40400000 address. See .mte_page section in boot.S + * and kernel.ld (where the address is effectively computed). + * + * Load .mte_page address into 'addr' register. + */ + adrp addr, .mte_page + add addr, addr, :lo12:.mte_page + + /* + * Set GCR for random tag generation. 0xA5 is just a random value to set + * GCR != 0 so the tag generated by 'irg' insn. is not zero, which is + * more interesting for the tests than when tag is zero. + */ + mov tmp0, 0xA5 + msr gcr_el1, tmp0 + + /* + * Generate a logical tag, add it to 'addr' address and put it into + * 'tagged_addr'. + */ + irg tagged_addr, addr + + /* + * Store the generated tag to memory region pointed to by 'addr', i.e. + * set the allocation tag for granule at 'addr'. The tag is extracted + * by stg from tagged_addr pointer. + */ + stg tagged_addr, [addr] + + /* + * Store a random value (0xdeadbeef) to tagged_addr address. This must + * not cause any Tag Check Fault since logical tag in tagged_addr and + * allocation tag associated with the memory pointed by tagged_addr are + * set the same, otherwise something is off and the test fails -- an + * exception is generated. + */ + ldr tmp1, =0xdeadbeef + str tmp1, [tagged_addr] + + /* This label is used by GDB Python script test-mte.py. */ +main_end: + ret + + /* + * See boot.S for details on the attributes set for this page and + * kernel.ld for where its location in memory is set. + */ + .section .mte_page