<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/kernel/trace, branch linux-6.17.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct()</title>
<updated>2025-12-12T17:40:19+00:00</updated>
<author>
<name>Song Liu</name>
<email>song@kernel.org</email>
</author>
<published>2025-10-27T17:50:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6fbdd023ee93deb74d9f0b0d66a7c556a25bce77'/>
<id>6fbdd023ee93deb74d9f0b0d66a7c556a25bce77</id>
<content type='text'>
[ Upstream commit 3e9a18e1c3e931abecf501cbb23d28d69f85bb56 ]

ftrace_hash_ipmodify_enable() checks IPMODIFY and DIRECT ftrace_ops on
the same kernel function. When needed, ftrace_hash_ipmodify_enable()
calls ops-&gt;ops_func() to prepare the direct ftrace (BPF trampoline) to
share the same function as the IPMODIFY ftrace (livepatch).

ftrace_hash_ipmodify_enable() is called in register_ftrace_direct() path,
but not called in modify_ftrace_direct() path. As a result, the following
operations will break livepatch:

1. Load livepatch to a kernel function;
2. Attach fentry program to the kernel function;
3. Attach fexit program to the kernel function.

After 3, the kernel function being used will not be the livepatched
version, but the original version.

Fix this by adding __ftrace_hash_update_ipmodify() to
__modify_ftrace_direct() and adjust some logic around the call.

Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20251027175023.1521602-3-song@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 3e9a18e1c3e931abecf501cbb23d28d69f85bb56 ]

ftrace_hash_ipmodify_enable() checks IPMODIFY and DIRECT ftrace_ops on
the same kernel function. When needed, ftrace_hash_ipmodify_enable()
calls ops-&gt;ops_func() to prepare the direct ftrace (BPF trampoline) to
share the same function as the IPMODIFY ftrace (livepatch).

ftrace_hash_ipmodify_enable() is called in register_ftrace_direct() path,
but not called in modify_ftrace_direct() path. As a result, the following
operations will break livepatch:

1. Load livepatch to a kernel function;
2. Attach fentry program to the kernel function;
3. Attach fexit program to the kernel function.

After 3, the kernel function being used will not be the livepatched
version, but the original version.

Fix this by adding __ftrace_hash_update_ipmodify() to
__modify_ftrace_direct() and adjust some logic around the call.

Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20251027175023.1521602-3-song@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: Fix WARN_ON in tracing_buffers_mmap_close for split VMAs</title>
<updated>2025-12-06T21:27:35+00:00</updated>
<author>
<name>Deepanshu Kartikey</name>
<email>kartikey406@gmail.com</email>
</author>
<published>2025-11-19T06:40:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=45053c12c45f0fb8ef6ab95118dd928d2fec0255'/>
<id>45053c12c45f0fb8ef6ab95118dd928d2fec0255</id>
<content type='text'>
commit b042fdf18e89a347177a49e795d8e5184778b5b6 upstream.

When a VMA is split (e.g., by partial munmap or MAP_FIXED), the kernel
calls vm_ops-&gt;close on each portion. For trace buffer mappings, this
results in ring_buffer_unmap() being called multiple times while
ring_buffer_map() was only called once.

This causes ring_buffer_unmap() to return -ENODEV on subsequent calls
because user_mapped is already 0, triggering a WARN_ON.

Trace buffer mappings cannot support partial mappings because the ring
buffer structure requires the complete buffer including the meta page.

Fix this by adding a may_split callback that returns -EINVAL to prevent
VMA splits entirely.

Cc: stable@vger.kernel.org
Fixes: cf9f0f7c4c5bb ("tracing: Allow user-space mapping of the ring-buffer")
Link: https://patch.msgid.link/20251119064019.25904-1-kartikey406@gmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a72c325b042aae6403c7
Tested-by: syzbot+a72c325b042aae6403c7@syzkaller.appspotmail.com
Reported-by: syzbot+a72c325b042aae6403c7@syzkaller.appspotmail.com
Signed-off-by: Deepanshu Kartikey &lt;kartikey406@gmail.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b042fdf18e89a347177a49e795d8e5184778b5b6 upstream.

When a VMA is split (e.g., by partial munmap or MAP_FIXED), the kernel
calls vm_ops-&gt;close on each portion. For trace buffer mappings, this
results in ring_buffer_unmap() being called multiple times while
ring_buffer_map() was only called once.

This causes ring_buffer_unmap() to return -ENODEV on subsequent calls
because user_mapped is already 0, triggering a WARN_ON.

Trace buffer mappings cannot support partial mappings because the ring
buffer structure requires the complete buffer including the meta page.

Fix this by adding a may_split callback that returns -EINVAL to prevent
VMA splits entirely.

Cc: stable@vger.kernel.org
Fixes: cf9f0f7c4c5bb ("tracing: Allow user-space mapping of the ring-buffer")
Link: https://patch.msgid.link/20251119064019.25904-1-kartikey406@gmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a72c325b042aae6403c7
Tested-by: syzbot+a72c325b042aae6403c7@syzkaller.appspotmail.com
Reported-by: syzbot+a72c325b042aae6403c7@syzkaller.appspotmail.com
Signed-off-by: Deepanshu Kartikey &lt;kartikey406@gmail.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace: Fix BPF fexit with livepatch</title>
<updated>2025-11-24T09:37:47+00:00</updated>
<author>
<name>Song Liu</name>
<email>song@kernel.org</email>
</author>
<published>2025-10-27T17:50:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=72d977150d30c70dfebb833fe941b38c98672095'/>
<id>72d977150d30c70dfebb833fe941b38c98672095</id>
<content type='text'>
commit 56b3c85e153b84f27e6cff39623ba40a1ad299d3 upstream.

When livepatch is attached to the same function as bpf trampoline with
a fexit program, bpf trampoline code calls register_ftrace_direct()
twice. The first time will fail with -EAGAIN, and the second time it
will succeed. This requires register_ftrace_direct() to unregister
the address on the first attempt. Otherwise, the bpf trampoline cannot
attach. Here is an easy way to reproduce this issue:

  insmod samples/livepatch/livepatch-sample.ko
  bpftrace -e 'fexit:cmdline_proc_show {}'
  ERROR: Unable to attach probe: fexit:vmlinux:cmdline_proc_show...

Fix this by cleaning up the hash when register_ftrace_function_nolock hits
errors.

Also, move the code that resets ops-&gt;func and ops-&gt;trampoline to the error
path of register_ftrace_direct(); and add a helper function reset_direct()
in register_ftrace_direct() and unregister_ftrace_direct().

Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use")
Cc: stable@vger.kernel.org # v6.6+
Reported-by: Andrey Grodzovsky &lt;andrey.grodzovsky@crowdstrike.com&gt;
Closes: https://lore.kernel.org/live-patching/c5058315a39d4615b333e485893345be@crowdstrike.com/
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Cc: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Acked-and-tested-by: Andrey Grodzovsky &lt;andrey.grodzovsky@crowdstrike.com&gt;
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20251027175023.1521602-2-song@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 56b3c85e153b84f27e6cff39623ba40a1ad299d3 upstream.

When livepatch is attached to the same function as bpf trampoline with
a fexit program, bpf trampoline code calls register_ftrace_direct()
twice. The first time will fail with -EAGAIN, and the second time it
will succeed. This requires register_ftrace_direct() to unregister
the address on the first attempt. Otherwise, the bpf trampoline cannot
attach. Here is an easy way to reproduce this issue:

  insmod samples/livepatch/livepatch-sample.ko
  bpftrace -e 'fexit:cmdline_proc_show {}'
  ERROR: Unable to attach probe: fexit:vmlinux:cmdline_proc_show...

Fix this by cleaning up the hash when register_ftrace_function_nolock hits
errors.

Also, move the code that resets ops-&gt;func and ops-&gt;trampoline to the error
path of register_ftrace_direct(); and add a helper function reset_direct()
in register_ftrace_direct() and unregister_ftrace_direct().

Fixes: d05cb470663a ("ftrace: Fix modification of direct_function hash while in use")
Cc: stable@vger.kernel.org # v6.6+
Reported-by: Andrey Grodzovsky &lt;andrey.grodzovsky@crowdstrike.com&gt;
Closes: https://lore.kernel.org/live-patching/c5058315a39d4615b333e485893345be@crowdstrike.com/
Cc: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Cc: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Acked-and-tested-by: Andrey Grodzovsky &lt;andrey.grodzovsky@crowdstrike.com&gt;
Signed-off-by: Song Liu &lt;song@kernel.org&gt;
Reviewed-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Link: https://lore.kernel.org/r/20251027175023.1521602-2-song@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Acked-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: Fix memory leaks in create_field_var()</title>
<updated>2025-11-13T20:37:45+00:00</updated>
<author>
<name>Zilin Guan</name>
<email>zilin@seu.edu.cn</email>
</author>
<published>2025-11-06T12:01:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a7b35dbd4b5a499681c96f411f76c7a100db03c4'/>
<id>a7b35dbd4b5a499681c96f411f76c7a100db03c4</id>
<content type='text'>
[ Upstream commit 80f0d631dcc76ee1b7755bfca1d8417d91d71414 ]

The function create_field_var() allocates memory for 'val' through
create_hist_field() inside parse_atom(), and for 'var' through
create_var(), which in turn allocates var-&gt;type and var-&gt;var.name
internally. Simply calling kfree() to release these structures will
result in memory leaks.

Use destroy_hist_field() to properly free 'val', and explicitly release
the memory of var-&gt;type and var-&gt;var.name before freeing 'var' itself.

Link: https://patch.msgid.link/20251106120132.3639920-1-zilin@seu.edu.cn
Fixes: 02205a6752f22 ("tracing: Add support for 'field variables'")
Signed-off-by: Zilin Guan &lt;zilin@seu.edu.cn&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 80f0d631dcc76ee1b7755bfca1d8417d91d71414 ]

The function create_field_var() allocates memory for 'val' through
create_hist_field() inside parse_atom(), and for 'var' through
create_var(), which in turn allocates var-&gt;type and var-&gt;var.name
internally. Simply calling kfree() to release these structures will
result in memory leaks.

Use destroy_hist_field() to properly free 'val', and explicitly release
the memory of var-&gt;type and var-&gt;var.name before freeing 'var' itself.

Link: https://patch.msgid.link/20251106120132.3639920-1-zilin@seu.edu.cn
Fixes: 02205a6752f22 ("tracing: Add support for 'field variables'")
Signed-off-by: Zilin Guan &lt;zilin@seu.edu.cn&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ring-buffer: Do not warn in ring_buffer_map_get_reader() when reader catches up</title>
<updated>2025-11-13T20:37:40+00:00</updated>
<author>
<name>Steven Rostedt</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2025-10-16T17:28:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6f5c4f8109fa4d0955b3712597a26b310bdc736f'/>
<id>6f5c4f8109fa4d0955b3712597a26b310bdc736f</id>
<content type='text'>
commit aa997d2d2a0b2e76f4df0f1f12829f02acb4fb6b upstream.

The function ring_buffer_map_get_reader() is a bit more strict than the
other get reader functions, and except for certain situations the
rb_get_reader_page() should not return NULL. If it does, it triggers a
warning.

This warning was triggering but after looking at why, it was because
another acceptable situation was happening and it wasn't checked for.

If the reader catches up to the writer and there's still data to be read
on the reader page, then the rb_get_reader_page() will return NULL as
there's no new page to get.

In this situation, the reader page should not be updated and no warning
should trigger.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Vincent Donnefort &lt;vdonnefort@google.com&gt;
Reported-by: syzbot+92a3745cea5ec6360309@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/690babec.050a0220.baf87.0064.GAE@google.com/
Link: https://lore.kernel.org/20251016132848.1b11bb37@gandalf.local.home
Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit aa997d2d2a0b2e76f4df0f1f12829f02acb4fb6b upstream.

The function ring_buffer_map_get_reader() is a bit more strict than the
other get reader functions, and except for certain situations the
rb_get_reader_page() should not return NULL. If it does, it triggers a
warning.

This warning was triggering but after looking at why, it was because
another acceptable situation was happening and it wasn't checked for.

If the reader catches up to the writer and there's still data to be read
on the reader page, then the rb_get_reader_page() will return NULL as
there's no new page to get.

In this situation, the reader page should not be updated and no warning
should trigger.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Cc: Vincent Donnefort &lt;vdonnefort@google.com&gt;
Reported-by: syzbot+92a3745cea5ec6360309@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/690babec.050a0220.baf87.0064.GAE@google.com/
Link: https://lore.kernel.org/20251016132848.1b11bb37@gandalf.local.home
Fixes: 117c39200d9d7 ("ring-buffer: Introducing ring-buffer mapping functions")
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: tprobe-events: Fix to put tracepoint_user when disable the tprobe</title>
<updated>2025-11-13T20:37:40+00:00</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2025-11-06T16:52:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d9168cda12ff51bb8fa5c12815e46203e9df5daa'/>
<id>d9168cda12ff51bb8fa5c12815e46203e9df5daa</id>
<content type='text'>
commit c91afa7610235f89a5e8f5686aac23892ab227ed upstream.

__unregister_trace_fprobe() checks tf-&gt;tuser to put it when removing
tprobe. However, disable_trace_fprobe() does not use it and only calls
unregister_fprobe(). Thus it forgets to disable tracepoint_user.

If the trace_fprobe has tuser, put it for unregistering the tracepoint
callbacks when disabling tprobe correctly.

Link: https://lore.kernel.org/all/176244794466.155515.3971904050506100243.stgit@devnote2/

Fixes: 2867495dea86 ("tracing: tprobe-events: Register tracepoint when enable tprobe event")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Tested-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Reviewed-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c91afa7610235f89a5e8f5686aac23892ab227ed upstream.

__unregister_trace_fprobe() checks tf-&gt;tuser to put it when removing
tprobe. However, disable_trace_fprobe() does not use it and only calls
unregister_fprobe(). Thus it forgets to disable tracepoint_user.

If the trace_fprobe has tuser, put it for unregistering the tracepoint
callbacks when disabling tprobe correctly.

Link: https://lore.kernel.org/all/176244794466.155515.3971904050506100243.stgit@devnote2/

Fixes: 2867495dea86 ("tracing: tprobe-events: Register tracepoint when enable tprobe event")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Tested-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Reviewed-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tracing: tprobe-events: Fix to register tracepoint correctly</title>
<updated>2025-11-13T20:37:40+00:00</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2025-11-06T16:52:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5b30f8e69da31fb1874ffebac83b7f083120036e'/>
<id>5b30f8e69da31fb1874ffebac83b7f083120036e</id>
<content type='text'>
commit 10d9dda426d684e98b17161f02f77894c6de9b60 upstream.

Since __tracepoint_user_init() calls tracepoint_user_register() without
initializing tuser-&gt;tpoint with given tracpoint, it does not register
tracepoint stub function as callback correctly, and tprobe does not work.

Initializing tuser-&gt;tpoint correctly before tracepoint_user_register()
so that it sets up tracepoint callback.

I confirmed below example works fine again.

echo "t sched_switch preempt prev_pid=prev-&gt;pid next_pid=next-&gt;pid" &gt; /sys/kernel/tracing/dynamic_events
echo 1 &gt; /sys/kernel/tracing/events/tracepoints/sched_switch/enable
cat /sys/kernel/tracing/trace_pipe

Link: https://lore.kernel.org/all/176244793514.155515.6466348656998627773.stgit@devnote2/

Fixes: 2867495dea86 ("tracing: tprobe-events: Register tracepoint when enable tprobe event")
Reported-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Tested-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Reviewed-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 10d9dda426d684e98b17161f02f77894c6de9b60 upstream.

Since __tracepoint_user_init() calls tracepoint_user_register() without
initializing tuser-&gt;tpoint with given tracpoint, it does not register
tracepoint stub function as callback correctly, and tprobe does not work.

Initializing tuser-&gt;tpoint correctly before tracepoint_user_register()
so that it sets up tracepoint callback.

I confirmed below example works fine again.

echo "t sched_switch preempt prev_pid=prev-&gt;pid next_pid=next-&gt;pid" &gt; /sys/kernel/tracing/dynamic_events
echo 1 &gt; /sys/kernel/tracing/events/tracepoints/sched_switch/enable
cat /sys/kernel/tracing/trace_pipe

Link: https://lore.kernel.org/all/176244793514.155515.6466348656998627773.stgit@devnote2/

Fixes: 2867495dea86 ("tracing: tprobe-events: Register tracepoint when enable tprobe event")
Reported-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Tested-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Reviewed-by: Beau Belgrave &lt;beaub@linux.microsoft.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ftrace: Fix softlockup in ftrace_module_enable</title>
<updated>2025-11-13T20:37:34+00:00</updated>
<author>
<name>Vladimir Riabchun</name>
<email>ferr.lambarginio@gmail.com</email>
</author>
<published>2025-09-12T11:28:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7e3c96010ade29bb340a5bdce8675f50c7f59001'/>
<id>7e3c96010ade29bb340a5bdce8675f50c7f59001</id>
<content type='text'>
[ Upstream commit 4099b98203d6b33d990586542fa5beee408032a3 ]

A soft lockup was observed when loading amdgpu module.
If a module has a lot of tracable functions, multiple calls
to kallsyms_lookup can spend too much time in RCU critical
section and with disabled preemption, causing kernel panic.
This is the same issue that was fixed in
commit d0b24b4e91fc ("ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY
kernels") and commit 42ea22e754ba ("ftrace: Add cond_resched() to
ftrace_graph_set_hash()").

Fix it the same way by adding cond_resched() in ftrace_module_enable.

Link: https://lore.kernel.org/aMQD9_lxYmphT-up@vova-pc
Signed-off-by: Vladimir Riabchun &lt;ferr.lambarginio@gmail.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 4099b98203d6b33d990586542fa5beee408032a3 ]

A soft lockup was observed when loading amdgpu module.
If a module has a lot of tracable functions, multiple calls
to kallsyms_lookup can spend too much time in RCU critical
section and with disabled preemption, causing kernel panic.
This is the same issue that was fixed in
commit d0b24b4e91fc ("ftrace: Prevent RCU stall on PREEMPT_VOLUNTARY
kernels") and commit 42ea22e754ba ("ftrace: Add cond_resched() to
ftrace_graph_set_hash()").

Fix it the same way by adding cond_resched() in ftrace_module_enable.

Link: https://lore.kernel.org/aMQD9_lxYmphT-up@vova-pc
Signed-off-by: Vladimir Riabchun &lt;ferr.lambarginio@gmail.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rv: Make rtapp/pagefault monitor depends on CONFIG_MMU</title>
<updated>2025-10-29T13:10:23+00:00</updated>
<author>
<name>Nam Cao</name>
<email>namcao@linutronix.de</email>
</author>
<published>2025-10-02T08:23:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ef6fb1fff2bb875af186e8129571c1aa05b6fd62'/>
<id>ef6fb1fff2bb875af186e8129571c1aa05b6fd62</id>
<content type='text'>
commit 3d62f95bd8450cebb4a4741bf83949cd54edd4a3 upstream.

There is no page fault without MMU. Compiling the rtapp/pagefault monitor
without CONFIG_MMU fails as page fault tracepoints' definitions are not
available.

Make rtapp/pagefault monitor depends on CONFIG_MMU.

Fixes: 9162620eb604 ("rv: Add rtapp_pagefault monitor")
Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202509260455.6Z9Vkty4-lkp@intel.com/
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Link: https://lore.kernel.org/r/20251002082317.973839-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3d62f95bd8450cebb4a4741bf83949cd54edd4a3 upstream.

There is no page fault without MMU. Compiling the rtapp/pagefault monitor
without CONFIG_MMU fails as page fault tracepoints' definitions are not
available.

Make rtapp/pagefault monitor depends on CONFIG_MMU.

Fixes: 9162620eb604 ("rv: Add rtapp_pagefault monitor")
Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Reported-by: kernel test robot &lt;lkp@intel.com&gt;
Closes: https://lore.kernel.org/oe-kbuild-all/202509260455.6Z9Vkty4-lkp@intel.com/
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Link: https://lore.kernel.org/r/20251002082317.973839-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>rv: Fully convert enabled_monitors to use list_head as iterator</title>
<updated>2025-10-29T13:10:23+00:00</updated>
<author>
<name>Nam Cao</name>
<email>namcao@linutronix.de</email>
</author>
<published>2025-10-02T08:22:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8948a0338d33c4a7ef1e0c439a3ad1d5fe9355ae'/>
<id>8948a0338d33c4a7ef1e0c439a3ad1d5fe9355ae</id>
<content type='text'>
commit 103541e6a5854b08a25e4caa61e990af1009a52e upstream.

The callbacks in enabled_monitors_seq_ops are inconsistent. Some treat the
iterator as struct rv_monitor *, while others treat the iterator as struct
list_head *.

This causes a wrong type cast and crashes the system as reported by Nathan.

Convert everything to use struct list_head * as iterator. This also makes
enabled_monitors consistent with available_monitors.

Fixes: de090d1ccae1 ("rv: Fix wrong type cast in enabled_monitors_next()")
Reported-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Closes: https://lore.kernel.org/linux-trace-kernel/20250923002004.GA2836051@ax162/
Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Link: https://lore.kernel.org/r/20251002082235.973099-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 103541e6a5854b08a25e4caa61e990af1009a52e upstream.

The callbacks in enabled_monitors_seq_ops are inconsistent. Some treat the
iterator as struct rv_monitor *, while others treat the iterator as struct
list_head *.

This causes a wrong type cast and crashes the system as reported by Nathan.

Convert everything to use struct list_head * as iterator. This also makes
enabled_monitors consistent with available_monitors.

Fixes: de090d1ccae1 ("rv: Fix wrong type cast in enabled_monitors_next()")
Reported-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Closes: https://lore.kernel.org/linux-trace-kernel/20250923002004.GA2836051@ax162/
Signed-off-by: Nam Cao &lt;namcao@linutronix.de&gt;
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Link: https://lore.kernel.org/r/20251002082235.973099-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco &lt;gmonaco@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
