52e63d67b5
In order for the page table level 5 to be in use, the CPU must have the setting enabled in addition to the CONFIG option. Check for the flag to be set to avoid false test failures on systems that do not have this cpu flag set. The test does a series of mmap calls including three using the MAP_FIXED flag and specifying an address that is 1<<47 or 1<<48. These addresses are only available if you are using level 5 page tables, which requires both the CPU to have the capabiltiy (la57 flag) and the kernel to be configured. Currently the test only checks for the kernel configuration option, so this test can still report a false positive. Here are the three failing lines: $ ./va_high_addr_switch | grep FAILED mmap(ADDR_SWITCH_HINT, 2 * PAGE_SIZE, MAP_FIXED): 0xffffffffffffffff - FAILED mmap(HIGH_ADDR, MAP_FIXED): 0xffffffffffffffff - FAILED mmap(ADDR_SWITCH_HINT, 2 * PAGE_SIZE, MAP_FIXED): 0xffffffffffffffff - FAILED I thought (for about a second) refactoring the test so that these three mmap calls will only be run on systems with the level 5 page tables available, but the whole point of the test is to check the level 5 feature... Link: https://lkml.kernel.org/r/20240119205801.62769-1-audra@redhat.com Fixes: 4f2930c6718a ("selftests/vm: only run 128TBswitch with 5-level paging") Signed-off-by: Audra Mitchell <audra@redhat.com> Cc: Rafael Aquini <raquini@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Adam Sindelar <adam@wowsignal.io> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
65 lines
1.6 KiB
Bash
Executable File
65 lines
1.6 KiB
Bash
Executable File
#!/bin/bash
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# SPDX-License-Identifier: GPL-2.0
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#
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# Copyright (C) 2022 Adam Sindelar (Meta) <adam@wowsignal.io>
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#
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# This is a test for mmap behavior with 5-level paging. This script wraps the
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# real test to check that the kernel is configured to support at least 5
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# pagetable levels.
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# 1 means the test failed
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exitcode=1
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# Kselftest framework requirement - SKIP code is 4.
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ksft_skip=4
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fail()
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{
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echo "$1"
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exit $exitcode
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}
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check_supported_x86_64()
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{
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local config="/proc/config.gz"
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[[ -f "${config}" ]] || config="/boot/config-$(uname -r)"
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[[ -f "${config}" ]] || fail "Cannot find kernel config in /proc or /boot"
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# gzip -dcfq automatically handles both compressed and plaintext input.
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# See man 1 gzip under '-f'.
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local pg_table_levels=$(gzip -dcfq "${config}" | grep PGTABLE_LEVELS | cut -d'=' -f 2)
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local cpu_supports_pl5=$(awk '/^flags/ {if (/la57/) {print 0;}
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else {print 1}; exit}' /proc/cpuinfo 2>/dev/null)
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if [[ "${pg_table_levels}" -lt 5 ]]; then
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echo "$0: PGTABLE_LEVELS=${pg_table_levels}, must be >= 5 to run this test"
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exit $ksft_skip
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elif [[ "${cpu_supports_pl5}" -ne 0 ]]; then
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echo "$0: CPU does not have the necessary la57 flag to support page table level 5"
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exit $ksft_skip
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fi
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}
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check_test_requirements()
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{
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# The test supports x86_64 and powerpc64. We currently have no useful
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# eligibility check for powerpc64, and the test itself will reject other
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# architectures.
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case `uname -m` in
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"x86_64")
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check_supported_x86_64
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;;
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*)
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return 0
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;;
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esac
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}
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check_test_requirements
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./va_high_addr_switch
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# In order to run hugetlb testcases, "--run-hugetlb" must be appended
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# to the binary.
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./va_high_addr_switch --run-hugetlb
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