[PATCH] x86: smpboot: Always log CPU numbers at info level

[David Sauerwein <dssauerw@amazon.de>]

announce_cpu uses pr_cont to log CPU numbers of a NUMA node on the same
log line across multiple calls of the function at info level. However,
if any other message is printed in between these calls, pr_cont is
unable to continue the previous message and logs a new line at
KERN_DEFAULT level. On systems where MESSAGE_LOGLEVEL_DEFAULT is left at
its default value, this causes these lines to show up at warn level.

[INFO][    0.051137] x86: Booting SMP configuration:
[INFO][    0.051139] .... node  #0, CPUs:        #1  #2  #3  #4  #5  #6  #7  #8  #9 #10 #11 #12 #13 #14 #15 #16 #17 #18 #19 #20 #21 #22 #23
[INFO][    0.056620] .... node  #1, CPUs:   #24
[INFO][    0.006767] smpboot: CPU 24 Converting physical 0 to logical die 1
[WARN][    0.056761]  #25 #26 #27 #28 #29 #30 #31 #32 #33 #34 #35 #36 #37 #38 #39 #40 #41 #42 #43 #44 #45 #46 #47
[INFO][    0.060721] .... node  #0, CPUs:   #48
[WARN][    0.060731] MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details.
[WARN][    0.060731] TAA CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html for more details.
[WARN][    0.060731] MMIO Stale Data CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/processor_mmio_stale_data.html for more details.
[WARN][    0.060731]  #49 #50 #51 #52 #53 #54 #55 #56 #57 #58 #59 #60 #61 #62 #63 #64 #65 #66 #67 #68 #69 #70 #71
[INFO][    0.068678] .... node  #1, CPUs:   #72 #73 #74 #75 #76 #77 #78 #79 #80 #81 #82 #83 #84 #85 #86 #87 #88 #89 #90 #91 #92 #93 #94 #95

(Example logs collected on a v5.10 based kernel)

Fix this by explicitly setting the log level to KERN_INFO when calling
pr_cont.

Reported-by: Paul Menzel <pmenzel@molgen.mpg.de>
Closes: https://lore.kernel.org/all/e964b2ae-7a15-a510-e76a-56d704949d62@molgen.mpg.de/
Suggested-by: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/all/871rdg8dyb.fsf@jogness.linutronix.de/
Signed-off-by: David Sauerwein <dssauerw@amazon.de>
---
 arch/x86/kernel/smpboot.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 294a8ea602986..4a5e2c0d6286d 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -949,7 +949,7 @@ static void announce_cpu(int cpu, int apicid)
 
 		if (node != current_node) {
 			if (current_node > (-1))
-				pr_cont("\n");
+				pr_cont(KERN_INFO "\n");
 			current_node = node;
 
 			printk(KERN_INFO ".... node %*s#%d, CPUs:  ",
@@ -958,10 +958,10 @@ static void announce_cpu(int cpu, int apicid)
 
 		/* Add padding for the BSP */
 		if (first)
-			pr_cont("%*s", width + 1, " ");
+			pr_cont(KERN_INFO "%*s", width + 1, " ");
 		first = 0;
 
-		pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu);
+		pr_cont(KERN_INFO "%*s#%d", width - num_digits(cpu), " ", cpu);
 	} else
 		pr_info("Booting Node %d Processor %d APIC 0x%x\n",
 			node, cpu, apicid);
-- 
2.47.3




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