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authorMike Travis <mike.travis@hpe.com>2018-10-02 13:01:46 -0500
committerThomas Gleixner <tglx@linutronix.de>2018-10-02 21:29:16 +0200
commit2647c43c7f3ba4b752bfce261d53b16e2f5bc9e3 (patch)
tree461a78b5c17f7f48c8790bba4b168418ba4d07c9 /arch
parent20a8378aa9dd108a01cb0e695599f5257a885c4b (diff)
downloadlinux-2647c43c7f3ba4b752bfce261d53b16e2f5bc9e3.tar.bz2
x86/tsc: Fix UV TSC initialization
The recent rework of the TSC calibration code introduced a regression on UV systems 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 that calls uv_system_init(). This informs tsc_sanitize_first_cpu() that the kernel runs 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 it 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") Suggested-by: Hedi Berriche <hedi.berriche@hpe.com> Signed-off-by: Mike Travis <mike.travis@hpe.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Russ Anderson <rja@hpe.com> Reviewed-by: Dimitri Sivanich <sivanich@hpe.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Russ Anderson <russ.anderson@hpe.com> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Len Brown <len.brown@intel.com> Cc: Dou Liyang <douly.fnst@cn.fujitsu.com> Cc: Xiaoming Gao <gxm.linux.kernel@gmail.com> Cc: Rajvi Jingar <rajvi.jingar@intel.com> Link: https://lkml.kernel.org/r/20181002180144.923579706@stormcage.americas.sgi.com
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/kernel/tsc.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 6490f618e096..b52bd2b6cdb4 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -26,6 +26,7 @@
#include <asm/apic.h>
#include <asm/intel-family.h>
#include <asm/i8259.h>
+#include <asm/uv/uv.h>
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();