Until LASS is merged into the kernel [1], LAM is left disabled in the config file. Running the LAM selftest with disabled LAM only results in unhelpful output. Use one of LAM syscalls() to determine whether the kernel was compiled with LAM support (CONFIG_ADDRESS_MASKING) or not. Skip running the tests in the latter case. [1] https://lore.kernel.org/all/20241028160917.1380714-1-alexander.shishkin@xxxxxxxxxxxxxxx/ Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman@xxxxxxxxx> Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Acked-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> --- Changelog v4: - Add this patch to the series. tools/testing/selftests/x86/lam.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/tools/testing/selftests/x86/lam.c b/tools/testing/selftests/x86/lam.c index 93f2f762d6b5..4ec37a4be007 100644 --- a/tools/testing/selftests/x86/lam.c +++ b/tools/testing/selftests/x86/lam.c @@ -124,6 +124,14 @@ static inline int cpu_has_lam(void) return (cpuinfo[0] & (1 << 26)); } +static inline int kernel_has_lam(void) +{ + unsigned long bits; + + syscall(SYS_arch_prctl, ARCH_GET_MAX_TAG_BITS, &bits); + return !!bits; +} + static inline int cpu_has_la57(void) { return !system("grep -wq la57 /proc/cpuinfo"); @@ -1181,6 +1189,11 @@ int main(int argc, char **argv) return KSFT_SKIP; } + if (!kernel_has_lam()) { + ksft_print_msg("LAM is disabled in the kernel!\n"); + return KSFT_SKIP; + } + while ((c = getopt(argc, argv, "ht:")) != -1) { switch (c) { case 't': -- 2.47.1
