Linux 5.15.130

Linux 5.15.130

[Greg Kroah-Hartman]

I'm announcing the release of the 5.15.130 kernel.

All users of the 5.15 kernel series must upgrade.

The updated 5.15.y git tree can be found at:
	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-5.15.y
and can be browsed at the normal kernel.org git web browser:
	https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary

thanks,

greg k-h

------------

 Documentation/admin-guide/kernel-parameters.txt |    4 --
 Makefile                                        |    2 -
 arch/arm/kernel/module-plts.c                   |    2 -
 arch/arm64/kernel/module-plts.c                 |    3 +-
 drivers/acpi/thermal.c                          |    6 ----
 include/linux/moduleloader.h                    |    5 +++
 kernel/module.c                                 |    2 -
 kernel/rcu/tasks.h                              |   36 +++++++++++++++++-------
 kernel/rcu/tree_exp.h                           |    5 ++-
 9 files changed, 41 insertions(+), 24 deletions(-)

Arnd Bergmann (1):
      arm64: module-plts: inline linux/moduleloader.h

Greg Kroah-Hartman (1):
      Linux 5.15.130

James Morse (3):
      module: Expose module_init_layout_section()
      arm64: module: Use module_init_layout_section() to spot init sections
      ARM: module: Use module_init_layout_section() to spot init sections

Mario Limonciello (1):
      ACPI: thermal: Drop nocrt parameter

Neeraj Upadhyay (1):
      rcu-tasks: Fix IPI failure handling in trc_wait_for_one_reader

Paul E. McKenney (3):
      rcu: Prevent expedited GP from enabling tick on offline CPU
      rcu-tasks: Wait for trc_read_check_handler() IPIs
      rcu-tasks: Add trc_inspect_reader() checks for exiting critical section

Re: Linux 5.15.130

[Greg Kroah-Hartman]

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index bb78526120f3..2cd4d66ab64c 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -5770,10 +5770,6 @@
 			-1: disable all critical trip points in all thermal zones
 			<degrees C>: override all critical trip points
 
-	thermal.nocrt=	[HW,ACPI]
-			Set to disable actions on ACPI thermal zone
-			critical and hot trip points.
-
 	thermal.off=	[HW,ACPI]
 			1: disable ACPI thermal control
 
diff --git a/Makefile b/Makefile
index 96c3f014094b..08cc0832e4d1 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 VERSION = 5
 PATCHLEVEL = 15
-SUBLEVEL = 129
+SUBLEVEL = 130
 EXTRAVERSION =
 NAME = Trick or Treat
 
diff --git a/arch/arm/kernel/module-plts.c b/arch/arm/kernel/module-plts.c
index 1fc309b41f94..8d809724cde5 100644
--- a/arch/arm/kernel/module-plts.c
+++ b/arch/arm/kernel/module-plts.c
@@ -256,7 +256,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 		/* sort by type and symbol index */
 		sort(rels, numrels, sizeof(Elf32_Rel), cmp_rel, NULL);
 
-		if (strncmp(secstrings + dstsec->sh_name, ".init", 5) != 0)
+		if (!module_init_layout_section(secstrings + dstsec->sh_name))
 			core_plts += count_plts(syms, dstsec->sh_addr, rels,
 						numrels, s->sh_info);
 		else
diff --git a/arch/arm64/kernel/module-plts.c b/arch/arm64/kernel/module-plts.c
index e53493d8b208..08fcbcb40d88 100644
--- a/arch/arm64/kernel/module-plts.c
+++ b/arch/arm64/kernel/module-plts.c
@@ -7,6 +7,7 @@
 #include <linux/ftrace.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/moduleloader.h>
 #include <linux/sort.h>
 
 static struct plt_entry __get_adrp_add_pair(u64 dst, u64 pc,
@@ -342,7 +343,7 @@ int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 		if (nents)
 			sort(rels, nents, sizeof(Elf64_Rela), cmp_rela, NULL);
 
-		if (!str_has_prefix(secstrings + dstsec->sh_name, ".init"))
+		if (!module_init_layout_section(secstrings + dstsec->sh_name))
 			core_plts += count_plts(syms, rels, numrels,
 						sechdrs[i].sh_info, dstsec);
 		else
diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
index 155bbabcc6f5..809e12b94123 100644
--- a/drivers/acpi/thermal.c
+++ b/drivers/acpi/thermal.c
@@ -59,10 +59,6 @@ static int tzp;
 module_param(tzp, int, 0444);
 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
 
-static int nocrt;
-module_param(nocrt, int, 0);
-MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
-
 static int off;
 module_param(off, int, 0);
 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
@@ -1132,7 +1128,7 @@ static int thermal_nocrt(const struct dmi_system_id *d) {
 
 	pr_notice("%s detected: disabling all critical thermal trip point actions.\n",
 		  d->ident);
-	nocrt = 1;
+	crt = -1;
 	return 0;
 }
 static int thermal_tzp(const struct dmi_system_id *d) {
diff --git a/include/linux/moduleloader.h b/include/linux/moduleloader.h
index 9e09d11ffe5b..1322652a9d0d 100644
--- a/include/linux/moduleloader.h
+++ b/include/linux/moduleloader.h
@@ -39,6 +39,11 @@ bool module_init_section(const char *name);
  */
 bool module_exit_section(const char *name);
 
+/* Describes whether within_module_init() will consider this an init section
+ * or not. This behaviour changes with CONFIG_MODULE_UNLOAD.
+ */
+bool module_init_layout_section(const char *sname);
+
 /*
  * Apply the given relocation to the (simplified) ELF.  Return -error
  * or 0.
diff --git a/kernel/module.c b/kernel/module.c
index 8a1766c69c6e..ed96295cc114 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2407,7 +2407,7 @@ static long get_offset(struct module *mod, unsigned int *size,
 	return ret;
 }
 
-static bool module_init_layout_section(const char *sname)
+bool module_init_layout_section(const char *sname)
 {
 #ifndef CONFIG_MODULE_UNLOAD
 	if (module_exit_section(sname))
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 94b8ee84bc78..28f628c70245 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -951,7 +951,7 @@ static void trc_read_check_handler(void *t_in)
 static bool trc_inspect_reader(struct task_struct *t, void *arg)
 {
 	int cpu = task_cpu(t);
-	bool in_qs = false;
+	int nesting;
 	bool ofl = cpu_is_offline(cpu);
 
 	if (task_curr(t)) {
@@ -971,18 +971,18 @@ static bool trc_inspect_reader(struct task_struct *t, void *arg)
 		n_heavy_reader_updates++;
 		if (ofl)
 			n_heavy_reader_ofl_updates++;
-		in_qs = true;
+		nesting = 0;
 	} else {
 		// The task is not running, so C-language access is safe.
-		in_qs = likely(!t->trc_reader_nesting);
+		nesting = t->trc_reader_nesting;
 	}
 
-	// Mark as checked so that the grace-period kthread will
-	// remove it from the holdout list.
-	t->trc_reader_checked = true;
-
-	if (in_qs)
-		return true;  // Already in quiescent state, done!!!
+	// If not exiting a read-side critical section, mark as checked
+	// so that the grace-period kthread will remove it from the
+	// holdout list.
+	t->trc_reader_checked = nesting >= 0;
+	if (nesting <= 0)
+		return !nesting;  // If in QS, done, otherwise try again later.
 
 	// The task is in a read-side critical section, so set up its
 	// state so that it will awaken the grace-period kthread upon exit
@@ -1041,9 +1041,11 @@ static void trc_wait_for_one_reader(struct task_struct *t,
 		if (smp_call_function_single(cpu, trc_read_check_handler, t, 0)) {
 			// Just in case there is some other reason for
 			// failure than the target CPU being offline.
+			WARN_ONCE(1, "%s():  smp_call_function_single() failed for CPU: %d\n",
+				  __func__, cpu);
 			rcu_tasks_trace.n_ipis_fails++;
 			per_cpu(trc_ipi_to_cpu, cpu) = false;
-			t->trc_ipi_to_cpu = cpu;
+			t->trc_ipi_to_cpu = -1;
 		}
 	}
 }
@@ -1164,14 +1166,28 @@ static void check_all_holdout_tasks_trace(struct list_head *hop,
 	}
 }
 
+static void rcu_tasks_trace_empty_fn(void *unused)
+{
+}
+
 /* Wait for grace period to complete and provide ordering. */
 static void rcu_tasks_trace_postgp(struct rcu_tasks *rtp)
 {
+	int cpu;
 	bool firstreport;
 	struct task_struct *g, *t;
 	LIST_HEAD(holdouts);
 	long ret;
 
+	// Wait for any lingering IPI handlers to complete.  Note that
+	// if a CPU has gone offline or transitioned to userspace in the
+	// meantime, all IPI handlers should have been drained beforehand.
+	// Yes, this assumes that CPUs process IPIs in order.  If that ever
+	// changes, there will need to be a recheck and/or timed wait.
+	for_each_online_cpu(cpu)
+		if (smp_load_acquire(per_cpu_ptr(&trc_ipi_to_cpu, cpu)))
+			smp_call_function_single(cpu, rcu_tasks_trace_empty_fn, NULL, 1);
+
 	// Remove the safety count.
 	smp_mb__before_atomic();  // Order vs. earlier atomics
 	atomic_dec(&trc_n_readers_need_end);
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index f46c0c1a5eb3..407941a2903b 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -507,7 +507,10 @@ static void synchronize_rcu_expedited_wait(void)
 				if (rdp->rcu_forced_tick_exp)
 					continue;
 				rdp->rcu_forced_tick_exp = true;
-				tick_dep_set_cpu(cpu, TICK_DEP_BIT_RCU_EXP);
+				preempt_disable();
+				if (cpu_online(cpu))
+					tick_dep_set_cpu(cpu, TICK_DEP_BIT_RCU_EXP);
+				preempt_enable();
 			}
 		}
 		j = READ_ONCE(jiffies_till_first_fqs);