Hi Linus,

Probes updates for v7.1

- fprobe: do not zero out unused fgraph_data. This removes unneeded
  memset of fgraph_data in fprobe entry handler.


Please pull the latest probes-v7.1 tree, which can be found at:


  git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git
probes-v7.1

Tag SHA1: bf593fe216d8bf264b53e0235145363623bc92f0
Head SHA1: e0a384434ae1bdfb03954c46c464e3dbd3223ad6


Martin Kaiser (1):
      tracing: fprobe: do not zero out unused fgraph_data

----
 kernel/trace/fprobe.c | 2 --
 1 file changed, 2 deletions(-)
---------------------------
commit e0a384434ae1bdfb03954c46c464e3dbd3223ad6
Author: Martin Kaiser <martin@kaiser.cx>
Date:   Wed Mar 25 00:47:01 2026 +0900

    tracing: fprobe: do not zero out unused fgraph_data
    
    If fprobe_entry does not fill the allocated fgraph_data completely, the
    unused part does not have to be zeroed.
    
    fgraph_data is a short-lived part of the shadow stack. The preceding
    length field allows locating the end regardless of the content.
    
    Link: https://lore.kernel.org/all/20260324084804.375764-1-martin@kaiser.cx/
    
    Signed-off-by: Martin Kaiser <martin@kaiser.cx>
    Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
index dcadf1d23b8a..56d145017902 100644
--- a/kernel/trace/fprobe.c
+++ b/kernel/trace/fprobe.c
@@ -450,8 +450,6 @@ static int fprobe_fgraph_entry(struct ftrace_graph_ent *trace, struct fgraph_ops
 				used += FPROBE_HEADER_SIZE_IN_LONG + size_words;
 		}
 	}
-	if (used < reserved_words)
-		memset(fgraph_data + used, 0, reserved_words - used);
 
 	/* If any exit_handler is set, data must be used. */
 	return used != 0;


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>

The pull request you sent on Fri, 17 Apr 2026 10:05:43 +0900:

> git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace.git probes-v7.1

has been merged into torvalds/linux.git:
https://git.kernel.org/torvalds/c/c9e03d59483a64967850e6d321b7fc56a957ef83

Thank you!

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