drop 1 patch based on RC review feedback

Dropped patches:

- "MIPS: smp: Report dying CPU to RCU in stop_this_cpu()"
  Queues: 6.1, 6.6
  Reason: build failure - rcutree_report_cpu_dead() does not exist before
  v6.7 (renamed from rcu_report_dead() in 448e9f34d91d); Huacai Chen asked
  for the sibling LoongArch patch to be dropped from 6.1/6.6 for the same
  reason and will send properly adapted backports
  Report: https://lore.kernel.org/stable/329cd36.6ac7d.19f25f6d0e3.Coremail.chenhuacai@loongson.cn/

Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/queue-6.1/mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch b/queue-6.1/mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch
deleted file mode 100644 (file)
index 92bb42b..0000000
--- a/queue-6.1/mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch
+++ /dev/null
@@ -1,71 +0,0 @@
-From 9f3f3bdc6d9dac1a5a8262ee7ad0f2ff1527a7e7 Mon Sep 17 00:00:00 2001
-From: Jonas Jelonek <jelonek.jonas@gmail.com>
-Date: Mon, 8 Jun 2026 09:37:29 +0000
-Subject: MIPS: smp: report dying CPU to RCU in stop_this_cpu()
-
-From: Jonas Jelonek <jelonek.jonas@gmail.com>
-
-commit 9f3f3bdc6d9dac1a5a8262ee7ad0f2ff1527a7e7 upstream.
-
-smp_send_stop() parks all secondary CPUs in stop_this_cpu(). The function
-marks the CPU offline for the scheduler via set_cpu_online(false) but
-never informs RCU, so RCU keeps expecting a quiescent state from CPUs
-that are now spinning forever with interrupts disabled.
-
-As long as nothing waits for an RCU grace period after smp_send_stop()
-this is harmless, which is why it went unnoticed. Since commit
-91840be8f710 ("irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT")
-however, irq_work_sync() calls synchronize_rcu() on architectures without
-an irq_work self-IPI, i.e. where arch_irq_work_has_interrupt() returns
-false. That is the asm-generic default used by MIPS. Any irq_work_sync()
-issued in the reboot/shutdown path after smp_send_stop() then blocks on
-a grace period that can never complete, hanging the reboot:
-
-  WARNING: CPU: 0 PID: 15 at kernel/irq_work.c:144 irq_work_queue_on
-  ...
-  rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
-  rcu: Offline CPU 1 blocking current GP.
-  rcu: Offline CPU 2 blocking current GP.
-  rcu: Offline CPU 3 blocking current GP.
-
-This issue was noticed on several Realtek MIPS switch SoCs (MIPS
-interAptiv) and came up during kernel bump downstream in OpenWrt from
-6.18.33 to 6.18.34, after the backport of the patch to the 6.18 stable
-branch. The patch also has been backported all the way back to 6.1.
-
-Call rcutree_report_cpu_dead() once interrupts are disabled, mirroring the
-generic CPU-hotplug offline path, so RCU stops waiting on the parked CPUs
-and grace periods can still complete. MIPS shuts down all CPUs here
-without going through the CPU-hotplug mechanism, so this report is not
-otherwise issued. Reporting a dying CPU to RCU outside the regular hotplug
-offline path is not unprecedented: arm64 does the same in cpu_die_early().
-There it is an exception for a CPU that was coming online and is aborting
-bringup, rather than the default shutdown action as on MIPS.
-
-Fixes: 91840be8f710 ("irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT")
-CC: stable@vger.kernel.org
-Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
-Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
----
- arch/mips/kernel/smp.c |    2 ++
- 1 file changed, 2 insertions(+)
-
---- a/arch/mips/kernel/smp.c
-+++ b/arch/mips/kernel/smp.c
-@@ -19,6 +19,7 @@
- #include <linux/sched/mm.h>
- #include <linux/cpumask.h>
- #include <linux/cpu.h>
-+#include <linux/rcupdate.h>
- #include <linux/err.h>
- #include <linux/ftrace.h>
- #include <linux/irqdomain.h>
-@@ -392,6 +393,7 @@ static void stop_this_cpu(void *dummy)
-       set_cpu_online(smp_processor_id(), false);
-       calculate_cpu_foreign_map();
-       local_irq_disable();
-+      rcutree_report_cpu_dead();
-       while (1);
- }
- 

diff --git a/queue-6.1/series b/queue-6.1/series
index 38d545c20a41e6eae5ef884718edb6b93fbc2153..66ba2ee35561b974c2c8dd35b3964c53d03a6c5e 100644 (file)
--- a/queue-6.1/series
+++ b/queue-6.1/series
@@ -97,7 +97,6 @@ irqchip-imgpdc-fix-resource-leak-add-missing-chained-handler-cleanup-on-remove.p
 fpga-region-fix-use-after-free-in-child_regions_with_firmware.patch
 ocfs2-reject-oversized-group-bitmap-descriptors.patch
 9p-avoid-putting-oldfid-in-p9_client_walk-error-path.patch
-mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch
 kvm-svm-fix-page-overflow-in-sev_dbg_crypt-for-encrypt-path.patch
 power-reset-linkstation-poweroff-fix-use-after-free-in-the-linkstation_poweroff_init.patch
 fbdev-fix-fb_new_modelist-to-prevent-null-ptr-deref-in-fb_videomode_to_var.patch

diff --git a/queue-6.6/mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch b/queue-6.6/mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch
deleted file mode 100644 (file)
index 56cad02..0000000
--- a/queue-6.6/mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch
+++ /dev/null
@@ -1,71 +0,0 @@
-From 9f3f3bdc6d9dac1a5a8262ee7ad0f2ff1527a7e7 Mon Sep 17 00:00:00 2001
-From: Jonas Jelonek <jelonek.jonas@gmail.com>
-Date: Mon, 8 Jun 2026 09:37:29 +0000
-Subject: MIPS: smp: report dying CPU to RCU in stop_this_cpu()
-
-From: Jonas Jelonek <jelonek.jonas@gmail.com>
-
-commit 9f3f3bdc6d9dac1a5a8262ee7ad0f2ff1527a7e7 upstream.
-
-smp_send_stop() parks all secondary CPUs in stop_this_cpu(). The function
-marks the CPU offline for the scheduler via set_cpu_online(false) but
-never informs RCU, so RCU keeps expecting a quiescent state from CPUs
-that are now spinning forever with interrupts disabled.
-
-As long as nothing waits for an RCU grace period after smp_send_stop()
-this is harmless, which is why it went unnoticed. Since commit
-91840be8f710 ("irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT")
-however, irq_work_sync() calls synchronize_rcu() on architectures without
-an irq_work self-IPI, i.e. where arch_irq_work_has_interrupt() returns
-false. That is the asm-generic default used by MIPS. Any irq_work_sync()
-issued in the reboot/shutdown path after smp_send_stop() then blocks on
-a grace period that can never complete, hanging the reboot:
-
-  WARNING: CPU: 0 PID: 15 at kernel/irq_work.c:144 irq_work_queue_on
-  ...
-  rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
-  rcu: Offline CPU 1 blocking current GP.
-  rcu: Offline CPU 2 blocking current GP.
-  rcu: Offline CPU 3 blocking current GP.
-
-This issue was noticed on several Realtek MIPS switch SoCs (MIPS
-interAptiv) and came up during kernel bump downstream in OpenWrt from
-6.18.33 to 6.18.34, after the backport of the patch to the 6.18 stable
-branch. The patch also has been backported all the way back to 6.1.
-
-Call rcutree_report_cpu_dead() once interrupts are disabled, mirroring the
-generic CPU-hotplug offline path, so RCU stops waiting on the parked CPUs
-and grace periods can still complete. MIPS shuts down all CPUs here
-without going through the CPU-hotplug mechanism, so this report is not
-otherwise issued. Reporting a dying CPU to RCU outside the regular hotplug
-offline path is not unprecedented: arm64 does the same in cpu_die_early().
-There it is an exception for a CPU that was coming online and is aborting
-bringup, rather than the default shutdown action as on MIPS.
-
-Fixes: 91840be8f710 ("irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT")
-CC: stable@vger.kernel.org
-Signed-off-by: Jonas Jelonek <jelonek.jonas@gmail.com>
-Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
-Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
----
- arch/mips/kernel/smp.c |    2 ++
- 1 file changed, 2 insertions(+)
-
---- a/arch/mips/kernel/smp.c
-+++ b/arch/mips/kernel/smp.c
-@@ -19,6 +19,7 @@
- #include <linux/sched/mm.h>
- #include <linux/cpumask.h>
- #include <linux/cpu.h>
-+#include <linux/rcupdate.h>
- #include <linux/err.h>
- #include <linux/ftrace.h>
- #include <linux/irqdomain.h>
-@@ -410,6 +411,7 @@ static void stop_this_cpu(void *dummy)
-       set_cpu_online(smp_processor_id(), false);
-       calculate_cpu_foreign_map();
-       local_irq_disable();
-+      rcutree_report_cpu_dead();
-       while (1);
- }
- 

diff --git a/queue-6.6/series b/queue-6.6/series
index 65942742a8226e5fb5fd878b7b2a1dcb021b69b7..49c02202cc560a6bd8a6c2f98403fe40c8cff003 100644 (file)
--- a/queue-6.6/series
+++ b/queue-6.6/series
@@ -151,7 +151,6 @@ fpga-region-fix-use-after-free-in-child_regions_with_firmware.patch
 rpmsg-char-fix-use-after-free-on-probe-error-path.patch
 ocfs2-reject-oversized-group-bitmap-descriptors.patch
 9p-avoid-putting-oldfid-in-p9_client_walk-error-path.patch
-mips-smp-report-dying-cpu-to-rcu-in-stop_this_cpu.patch
 kvm-x86-hyper-v-bound-the-bank-index-when-querying-sparse-banks.patch
 kvm-svm-fix-page-overflow-in-sev_dbg_crypt-for-encrypt-path.patch
 power-reset-linkstation-poweroff-fix-use-after-free-in-the-linkstation_poweroff_init.patch