Fix regression introduced by

commit cf7a63ef4e02 ("x86/tsc: Calibrate tsc only once")

as it changed setup_arch() so that it now calls tsc_early_init() before
acpi_boot_table_init() which is a necessary step, in the case of UV
systems, to inform 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 tsc_early_init() on UV systems and let TSC initialization
take place later in tsc_init().

Fixes: cf7a63ef4e02 ("x86/tsc: Calibrate tsc only once") 
Signed-off-by: Mike Travis <[email protected]>
Signed-off-by: Hedi Berriche <[email protected]>
Reviewed-by: Russ Anderson <[email protected]>
Reviewed-by: Dimitri Sivanich <[email protected]>
---
 arch/x86/kernel/setup.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- linux.orig/arch/x86/kernel/setup.c
+++ linux/arch/x86/kernel/setup.c
@@ -117,6 +117,7 @@
 #include <asm/microcode.h>
 #include <asm/kaslr.h>
 #include <asm/unwind.h>
+#include <asm/uv/uv.h>
 
 /*
  * max_low_pfn_mapped: highest direct mapped pfn under 4GB
@@ -1015,7 +1016,10 @@ void __init setup_arch(char **cmdline_p)
         */
        init_hypervisor_platform();
 
-       tsc_early_init();
+       /* UV TSC multi-chassis synchronization already set, don't change it */
+       if (!is_early_uv_system())
+               tsc_early_init();
+
        x86_init.resources.probe_roms();
 
        /* after parse_early_param, so could debug it */

-- 

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