x86/microcode/intel: Do not print microcode revision and processor flags

collect_cpu_info() is used to collect the current microcode revision and
processor flags on every CPU.

It had a weird mechanism to try to mimick a "once" functionality in the
sense that, that information should be issued only when it is differing
from the previous CPU.

However (1):

the new calling sequence started doing that in parallel:

  microcode_init()
  |-> schedule_on_each_cpu(setup_online_cpu)
      |-> collect_cpu_info()

resulting in multiple redundant prints:

  microcode: sig=0x50654, pf=0x80, revision=0x2006e05
  microcode: sig=0x50654, pf=0x80, revision=0x2006e05
  microcode: sig=0x50654, pf=0x80, revision=0x2006e05

However (2):

dumping this here is not that important because the kernel does not
support mixed silicon steppings microcode. Finally!

Besides, there is already a pr_info() in microcode_reload_late() that
shows both the old and new revisions.

What is more, the CPU signature (sig=0x50654) and Processor Flags
(pf=0x80) above aren't that useful to the end user, they are available
via /proc/cpuinfo and they don't change anyway.

Remove the redundant pr_info().

  [ bp: Heavily massage. ]

Fixes: b6f86689d5b7 ("x86/microcode: Rip out the subsys interface gunk")
Reported-by: Tony Luck <[email protected]>
Signed-off-by: Ashok Raj <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index c4a00fb97f618434dc3b109dfdd69a50a2fe2cd6..4f93875f57b422207c272c70153918fb1e9ca0db 100644 (file)
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -554,7 +554,6 @@ void reload_ucode_intel(void)
 
 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 {
-       static struct cpu_signature prev;
        struct cpuinfo_x86 *c = &cpu_data(cpu_num);
        unsigned int val[2];
 
@@ -570,13 +569,6 @@ static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 
        csig->rev = c->microcode;
 
-       /* No extra locking on prev, races are harmless. */
-       if (csig->sig != prev.sig || csig->pf != prev.pf || csig->rev != prev.rev) {
-               pr_info("sig=0x%x, pf=0x%x, revision=0x%x\n",
-                       csig->sig, csig->pf, csig->rev);
-               prev = *csig;
-       }
-
        return 0;
 }