Subject: linux-next: manual merge of the rcu tree with the ftrace tree

From: Stephen Rothwell <[email-masked]>
Date: Fri, 14 Nov 2025 13:52:26 +1100

Hi all,

Today's linux-next merge of the rcu tree got a conflict in:

  kernel/trace/trace_syscalls.c

between commit:

  a544d9a66bdf ("tracing: Have syscall trace events read user space string")

from the ftrace tree and commit:

  35587dbc58dd ("tracing: Guard __DECLARE_TRACE() use of __DO_TRACE_CALL() with SRCU-fast")

from the rcu tree.

I fixed it up (Maybe - see below) and can carry the fix as necessary. This
is now fixed as far as linux-next is concerned, but any non trivial
conflicts should be mentioned to your upstream maintainer when your tree
is submitted for merging.  You may also want to consider cooperating
with the maintainer of the conflicting tree to minimise any particularly
complex conflicts.

-- 
Cheers,
Stephen Rothwell

diff --cc kernel/trace/trace_syscalls.c
index e96d0063cbcf,3f699b198c56..000000000000
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@@ -878,6 -322,8 +890,7 @@@ static void ftrace_syscall_enter(void *
  	 * buffer and per-cpu data require preemption to be disabled.
  	 */
  	might_fault();
+ 	preempt_rt_guard();
 -	guard(preempt_notrace)();
  
  	syscall_nr = trace_get_syscall_nr(current, regs);
  	if (syscall_nr < 0 || syscall_nr >= NR_syscalls)