5.15-stable patches

added patches:
	tracing-zero-the-pipe-cpumask-on-alloc-to-avoid-spurious-ebusy.patch

diff --git a/queue-5.15/series b/queue-5.15/series
index 08deae85fdada5d3c7865a24326feccba4e6826d..ecb45226ddb8b84980d4ef4ea2f19d28f1ebaa09 100644 (file)
--- a/queue-5.15/series
+++ b/queue-5.15/series
@@ -373,3 +373,4 @@ usb-core-fix-oversight-in-superspeed-initialization.patch
 x86-sgx-break-up-long-non-preemptible-delays-in-sgx_vepc_release.patch
 perf-x86-uncore-correct-the-number-of-chas-on-emr.patch
 net-remove-duplicate-indirect_callable_declare-of-udp_ehashfn.patch
+tracing-zero-the-pipe-cpumask-on-alloc-to-avoid-spurious-ebusy.patch

diff --git a/queue-5.15/tracing-zero-the-pipe-cpumask-on-alloc-to-avoid-spurious-ebusy.patch b/queue-5.15/tracing-zero-the-pipe-cpumask-on-alloc-to-avoid-spurious-ebusy.patch
new file mode 100644 (file)
index 0000000..42ecd7a
--- /dev/null
+++ b/queue-5.15/tracing-zero-the-pipe-cpumask-on-alloc-to-avoid-spurious-ebusy.patch
@@ -0,0 +1,53 @@
+From 3d07fa1dd19035eb0b13ae6697efd5caa9033e74 Mon Sep 17 00:00:00 2001
+From: Brian Foster <bfoster@redhat.com>
+Date: Thu, 31 Aug 2023 08:55:00 -0400
+Subject: tracing: Zero the pipe cpumask on alloc to avoid spurious -EBUSY
+
+From: Brian Foster <bfoster@redhat.com>
+
+commit 3d07fa1dd19035eb0b13ae6697efd5caa9033e74 upstream.
+
+The pipe cpumask used to serialize opens between the main and percpu
+trace pipes is not zeroed or initialized. This can result in
+spurious -EBUSY returns if underlying memory is not fully zeroed.
+This has been observed by immediate failure to read the main
+trace_pipe file on an otherwise newly booted and idle system:
+
+ # cat /sys/kernel/debug/tracing/trace_pipe
+ cat: /sys/kernel/debug/tracing/trace_pipe: Device or resource busy
+
+Zero the allocation of pipe_cpumask to avoid the problem.
+
+Link: https://lore.kernel.org/linux-trace-kernel/20230831125500.986862-1-bfoster@redhat.com
+
+Cc: stable@vger.kernel.org
+Fixes: c2489bb7e6be ("tracing: Introduce pipe_cpumask to avoid race on trace_pipes")
+Reviewed-by: Zheng Yejian <zhengyejian1@huawei.com>
+Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
+Signed-off-by: Brian Foster <bfoster@redhat.com>
+Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ kernel/trace/trace.c |    4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/kernel/trace/trace.c
++++ b/kernel/trace/trace.c
+@@ -9350,7 +9350,7 @@ static struct trace_array *trace_array_c
+       if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL))
+               goto out_free_tr;
+ 
+-      if (!alloc_cpumask_var(&tr->pipe_cpumask, GFP_KERNEL))
++      if (!zalloc_cpumask_var(&tr->pipe_cpumask, GFP_KERNEL))
+               goto out_free_tr;
+ 
+       tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS;
+@@ -10208,7 +10208,7 @@ __init static int tracer_alloc_buffers(v
+       if (trace_create_savedcmd() < 0)
+               goto out_free_temp_buffer;
+ 
+-      if (!alloc_cpumask_var(&global_trace.pipe_cpumask, GFP_KERNEL))
++      if (!zalloc_cpumask_var(&global_trace.pipe_cpumask, GFP_KERNEL))
+               goto out_free_savedcmd;
+ 
+       /* TODO: make the number of buffers hot pluggable with CPUS */