4.19-stable patches

added patches:
	perf-x86-intel-delay-memory-deallocation-until-x86_pmu_dead_cpu.patch

diff --git a/queue-4.19/perf-x86-intel-delay-memory-deallocation-until-x86_pmu_dead_cpu.patch b/queue-4.19/perf-x86-intel-delay-memory-deallocation-until-x86_pmu_dead_cpu.patch
new file mode 100644 (file)
index 0000000..c1c0c6a
--- /dev/null
+++ b/queue-4.19/perf-x86-intel-delay-memory-deallocation-until-x86_pmu_dead_cpu.patch
@@ -0,0 +1,104 @@
+From 602cae04c4864bb3487dfe4c2126c8d9e7e1614a Mon Sep 17 00:00:00 2001
+From: Peter Zijlstra <peterz@infradead.org>
+Date: Wed, 19 Dec 2018 17:53:50 +0100
+Subject: perf/x86/intel: Delay memory deallocation until x86_pmu_dead_cpu()
+
+From: Peter Zijlstra <peterz@infradead.org>
+
+commit 602cae04c4864bb3487dfe4c2126c8d9e7e1614a upstream.
+
+intel_pmu_cpu_prepare() allocated memory for ->shared_regs among other
+members of struct cpu_hw_events. This memory is released in
+intel_pmu_cpu_dying() which is wrong. The counterpart of the
+intel_pmu_cpu_prepare() callback is x86_pmu_dead_cpu().
+
+Otherwise if the CPU fails on the UP path between CPUHP_PERF_X86_PREPARE
+and CPUHP_AP_PERF_X86_STARTING then it won't release the memory but
+allocate new memory on the next attempt to online the CPU (leaking the
+old memory).
+Also, if the CPU down path fails between CPUHP_AP_PERF_X86_STARTING and
+CPUHP_PERF_X86_PREPARE then the CPU will go back online but never
+allocate the memory that was released in x86_pmu_dying_cpu().
+
+Make the memory allocation/free symmetrical in regard to the CPU hotplug
+notifier by moving the deallocation to intel_pmu_cpu_dead().
+
+This started in commit:
+
+   a7e3ed1e47011 ("perf: Add support for supplementary event registers").
+
+In principle the bug was introduced in v2.6.39 (!), but it will almost
+certainly not backport cleanly across the big CPU hotplug rewrite between v4.7-v4.15...
+
+[ bigeasy: Added patch description. ]
+[ mingo: Added backporting guidance. ]
+
+Reported-by: He Zhe <zhe.he@windriver.com>
+Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With developer hat on
+Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
+Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> # With maintainer hat on
+Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
+Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
+Cc: Jiri Olsa <jolsa@redhat.com>
+Cc: Linus Torvalds <torvalds@linux-foundation.org>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Thomas Gleixner <tglx@linutronix.de>
+Cc: acme@kernel.org
+Cc: bp@alien8.de
+Cc: hpa@zytor.com
+Cc: jolsa@kernel.org
+Cc: kan.liang@linux.intel.com
+Cc: namhyung@kernel.org
+Cc: <stable@vger.kernel.org>
+Fixes: a7e3ed1e47011 ("perf: Add support for supplementary event registers").
+Link: https://lkml.kernel.org/r/20181219165350.6s3jvyxbibpvlhtq@linutronix.de
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+[ He Zhe: Fixes conflict caused by missing disable_counter_freeze which is
+ introduced since v4.20 af3bdb991a5cb. ]
+Signed-off-by: He Zhe <zhe.he@windriver.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/x86/events/intel/core.c |   10 ++++++++--
+ 1 file changed, 8 insertions(+), 2 deletions(-)
+
+--- a/arch/x86/events/intel/core.c
++++ b/arch/x86/events/intel/core.c
+@@ -3440,6 +3440,11 @@ static void free_excl_cntrs(int cpu)
+ 
+ static void intel_pmu_cpu_dying(int cpu)
+ {
++      fini_debug_store_on_cpu(cpu);
++}
++
++static void intel_pmu_cpu_dead(int cpu)
++{
+       struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
+       struct intel_shared_regs *pc;
+ 
+@@ -3451,8 +3456,6 @@ static void intel_pmu_cpu_dying(int cpu)
+       }
+ 
+       free_excl_cntrs(cpu);
+-
+-      fini_debug_store_on_cpu(cpu);
+ }
+ 
+ static void intel_pmu_sched_task(struct perf_event_context *ctx,
+@@ -3541,6 +3544,7 @@ static __initconst const struct x86_pmu
+       .cpu_prepare            = intel_pmu_cpu_prepare,
+       .cpu_starting           = intel_pmu_cpu_starting,
+       .cpu_dying              = intel_pmu_cpu_dying,
++      .cpu_dead               = intel_pmu_cpu_dead,
+ };
+ 
+ static struct attribute *intel_pmu_attrs[];
+@@ -3581,6 +3585,8 @@ static __initconst const struct x86_pmu
+       .cpu_prepare            = intel_pmu_cpu_prepare,
+       .cpu_starting           = intel_pmu_cpu_starting,
+       .cpu_dying              = intel_pmu_cpu_dying,
++      .cpu_dead               = intel_pmu_cpu_dead,
++
+       .guest_get_msrs         = intel_guest_get_msrs,
+       .sched_task             = intel_pmu_sched_task,
+ };

diff --git a/queue-4.19/series b/queue-4.19/series
index d2c85caa9e4ce5b0c3f28fa5a81d863282fdbe28..1a0433999a008085f4ba39632591118a9c63a34c 100644 (file)
--- a/queue-4.19/series
+++ b/queue-4.19/series
@@ -310,3 +310,4 @@ serial-8250_pci-make-pci-class-test-non-fatal.patch
 serial-sh-sci-do-not-free-irqs-that-have-already-been-freed.patch
 cacheinfo-keep-the-old-value-if-of_property_read_u32-fails.patch
 ib-hfi1-add-limit-test-for-rc-uc-send-via-loopback.patch
+perf-x86-intel-delay-memory-deallocation-until-x86_pmu_dead_cpu.patch