Fix regression introduced by commit cf7a63ef4e02 ("x86/tsc: Calibrate tsc only once") as it added a call to tsc_early_init() which initializes the TSC ADJUST values before acpi_boot_table_init(). In the case of UV systems, that is a necessary step thats calls uv_system_init(). This informs tsc_sanitize_first_cpu() that we're on a platform with async TSC resets as documented in commit 341102c3ef29 ("x86/tsc: Add option that TSC on Socket 0 being non-zero is valid") Fix by skipping the early tsc initialization on UV systems and let TSC init tests take place later in tsc_init(). Fixes: cf7a63ef4e02 ("x86/tsc: Calibrate tsc only once") Signed-off-by: Mike Travis Suggested-by: Hedi Berriche Reviewed-by: Russ Anderson Reviewed-by: Dimitri Sivanich --- arch/x86/kernel/tsc.c | 4 ++++ 1 file changed, 4 insertions(+) --- linux.orig/arch/x86/kernel/tsc.c +++ linux/arch/x86/kernel/tsc.c @@ -26,6 +26,7 @@ #include #include #include +#include unsigned int __read_mostly cpu_khz; /* TSC clocks / usec, not used here */ EXPORT_SYMBOL(cpu_khz); @@ -1433,6 +1434,9 @@ void __init tsc_early_init(void) { if (!boot_cpu_has(X86_FEATURE_TSC)) return; + /* Don't change UV TSC multi-chassis synchronization */ + if (is_early_uv_system()) + return; if (!determine_cpu_tsc_frequencies(true)) return; loops_per_jiffy = get_loops_per_jiffy(); --