tracing/fprobe: Avoid kcalloc() in rcu_read_lock section

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fprobe_remove_node_in_module() is called under RCU read locked, but
this invokes kcalloc() if there are more than 8 fprobes installed
on the module. Sashiko warns it because kcalloc() can sleep [1].

 [1] https://sashiko.dev/#/patchset/177552432201.853249.5125045538812833325.stgit%40mhiramat.tok.corp.google.com

To fix this issue, expand the batch size to 128 and do not expand
the fprobe_addr_list, but just cancel walking on fprobe_ip_table,
update fgraph/ftrace_ops and retry the loop again.

Link: https://lore.kernel.org/all/177669367206.132053.1493637946869032744.stgit@mhiramat.tok.corp.google.com/

Fixes: 0de4c70d04 ("tracing: fprobe: use rhltable for fprobe_ip_table")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

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This commit is contained in:

Masami Hiramatsu (Google) 2026-04-20 23:01:12 +09:00

parent 845947aca6

commit aa72812b49

1 changed files with 45 additions and 47 deletions

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kernel/trace/fprobe.c

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