5.15-stable patches

added patches:
	tick-nohz-unexport-__init-annotated-tick_nohz_full_setup.patch

diff --git a/queue-5.15/series b/queue-5.15/series
new file mode 100644 (file)
index 0000000..4c96f37
--- /dev/null
+++ b/queue-5.15/series
@@ -0,0 +1 @@
+tick-nohz-unexport-__init-annotated-tick_nohz_full_setup.patch

diff --git a/queue-5.15/tick-nohz-unexport-__init-annotated-tick_nohz_full_setup.patch b/queue-5.15/tick-nohz-unexport-__init-annotated-tick_nohz_full_setup.patch
new file mode 100644 (file)
index 0000000..373cafb
--- /dev/null
+++ b/queue-5.15/tick-nohz-unexport-__init-annotated-tick_nohz_full_setup.patch
@@ -0,0 +1,49 @@
+From 2390095113e98fc52fffe35c5206d30d9efe3f78 Mon Sep 17 00:00:00 2001
+From: Masahiro Yamada <masahiroy@kernel.org>
+Date: Mon, 27 Jun 2022 12:22:09 +0900
+Subject: tick/nohz: unexport __init-annotated tick_nohz_full_setup()
+
+From: Masahiro Yamada <masahiroy@kernel.org>
+
+commit 2390095113e98fc52fffe35c5206d30d9efe3f78 upstream.
+
+EXPORT_SYMBOL and __init is a bad combination because the .init.text
+section is freed up after the initialization. Hence, modules cannot
+use symbols annotated __init. The access to a freed symbol may end up
+with kernel panic.
+
+modpost used to detect it, but it had been broken for a decade.
+
+Commit 28438794aba4 ("modpost: fix section mismatch check for exported
+init/exit sections") fixed it so modpost started to warn it again, then
+this showed up:
+
+    MODPOST vmlinux.symvers
+  WARNING: modpost: vmlinux.o(___ksymtab_gpl+tick_nohz_full_setup+0x0): Section mismatch in reference from the variable __ksymtab_tick_nohz_full_setup to the function .init.text:tick_nohz_full_setup()
+  The symbol tick_nohz_full_setup is exported and annotated __init
+  Fix this by removing the __init annotation of tick_nohz_full_setup or drop the export.
+
+Drop the export because tick_nohz_full_setup() is only called from the
+built-in code in kernel/sched/isolation.c.
+
+Fixes: ae9e557b5be2 ("time: Export tick start/stop functions for rcutorture")
+Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
+Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
+Tested-by: Paul E. McKenney <paulmck@kernel.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Thomas Backlund <tmb@tmb.nu>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/time/tick-sched.c |    1 -
+ 1 file changed, 1 deletion(-)
+
+--- a/kernel/time/tick-sched.c
++++ b/kernel/time/tick-sched.c
+@@ -509,7 +509,6 @@ void __init tick_nohz_full_setup(cpumask
+       cpumask_copy(tick_nohz_full_mask, cpumask);
+       tick_nohz_full_running = true;
+ }
+-EXPORT_SYMBOL_GPL(tick_nohz_full_setup);
+ 
+ static int tick_nohz_cpu_down(unsigned int cpu)
+ {