summarylogtreecommitdiffstats
path: root/0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch
diff options
context:
space:
mode:
authorgraysky2022-04-13 06:33:14 -0400
committergraysky2022-04-13 06:33:14 -0400
commit51ada6c0f5ade1b03716f83641c4ef030d173faf (patch)
tree52adfbc7095af41d3d98a90210be1f3f94938aae /0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch
parent779064652f54ae6826d7e18090020d4a71c90121 (diff)
downloadaur-51ada6c0f5ade1b03716f83641c4ef030d173faf.tar.gz
Update to 5.17.3rc1-1
Diffstat (limited to '0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch')
-rw-r--r--0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch55
1 files changed, 55 insertions, 0 deletions
diff --git a/0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch b/0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch
new file mode 100644
index 00000000000..2be273d5c3c
--- /dev/null
+++ b/0006-lib-irq_poll-Declare-IRQ_POLL-softirq-vector-as-ksof.patch
@@ -0,0 +1,55 @@
+From 43a520143b091d79168ca3284aa23501c09f711e Mon Sep 17 00:00:00 2001
+From: Frederic Weisbecker <frederic@kernel.org>
+Date: Tue, 8 Feb 2022 17:16:35 +0100
+Subject: [PATCH 6/9] lib/irq_poll: Declare IRQ_POLL softirq vector as
+ ksoftirqd-parking safe
+
+The following warning may appear while setting a CPU down:
+
+ NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #20!!!
+
+The IRQ_POLL_SOFTIRQ vector can be raised during the hotplug cpu_down()
+path after ksoftirqd is parked and before the CPU actually dies. However
+this is handled afterward at the CPUHP_IRQ_POLL_DEAD stage where the
+queue gets migrated.
+
+Hence this warning can be considered spurious and the vector can join
+the "hotplug-safe" list.
+
+Reported-and-tested-by: Paul Menzel <pmenzel@molgen.mpg.de>
+Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Paul E. McKenney <paulmck@kernel.org>
+Cc: Paul Menzel <pmenzel@molgen.mpg.de>
+---
+ include/linux/interrupt.h | 11 +++++++----
+ 1 file changed, 7 insertions(+), 4 deletions(-)
+
+diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
+index 9613326d2f8a..f40754caaefa 100644
+--- a/include/linux/interrupt.h
++++ b/include/linux/interrupt.h
+@@ -580,12 +580,15 @@ enum
+ };
+
+ /*
+- * Ignoring the RCU vector after ksoftirqd is parked is fine
+- * because:
+- * 1) rcutree_migrate_callbacks() takes care of the queue.
++ * The following vectors can be safely ignored after ksoftirqd is parked:
++ *
++ * _ RCU:
++ * 1) rcutree_migrate_callbacks() migrates the queue.
+ * 2) rcu_report_dead() reports the final quiescent states.
++ *
++ * _ IRQ_POLL: irq_poll_cpu_dead() migrates the queue
+ */
+-#define SOFTIRQ_HOTPLUG_SAFE_MASK (BIT(RCU_SOFTIRQ))
++#define SOFTIRQ_HOTPLUG_SAFE_MASK (BIT(RCU_SOFTIRQ) | BIT(IRQ_POLL_SOFTIRQ))
+
+ /* map softirq index to softirq name. update 'softirq_to_name' in
+ * kernel/softirq.c when adding a new softirq.
+--
+2.35.1
+