The text patching functions which are invoked from jump_label and kprobes
code are protected against cpu hotplug at the call sites.

Use stop_machine_cpuslocked() to avoid recursion on the cpu hotplug
rwsem. stop_machine_cpuslocked() contains a lockdep assertion to catch any
unprotected callers.

Signed-off-by: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: Russell King <[email protected]>
---
 arch/arm/kernel/patch.c        |    2 +-
 arch/arm/probes/kprobes/core.c |    3 ++-
 2 files changed, 3 insertions(+), 2 deletions(-)

--- a/arch/arm/kernel/patch.c
+++ b/arch/arm/kernel/patch.c
@@ -124,5 +124,5 @@ void __kprobes patch_text(void *addr, un
                .insn = insn,
        };
 
-       stop_machine(patch_text_stop_machine, &patch, NULL);
+       stop_machine_cpuslocked(patch_text_stop_machine, &patch, NULL);
 }
--- a/arch/arm/probes/kprobes/core.c
+++ b/arch/arm/probes/kprobes/core.c
@@ -182,7 +182,8 @@ void __kprobes kprobes_remove_breakpoint
                .addr = addr,
                .insn = insn,
        };
-       stop_machine(__kprobes_remove_breakpoint, &p, cpu_online_mask);
+       stop_machine_cpuslocked(__kprobes_remove_breakpoint, &p,
+                               cpu_online_mask);
 }
 
 void __kprobes arch_disarm_kprobe(struct kprobe *p)


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