| Date | Wed, 24 May 2017 10:15:39 +0200 | From | Thomas Gleixner <> | Subject | [patch V3 28/32] s390: Prevent hotplug rwsem recursion |
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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 <tglx@linutronix.de> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux-s390@vger.kernel.org --- arch/s390/kernel/jump_label.c | 2 +- arch/s390/kernel/kprobes.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-)
--- a/arch/s390/kernel/jump_label.c +++ b/arch/s390/kernel/jump_label.c @@ -93,7 +93,7 @@ void arch_jump_label_transform(struct ju args.entry = entry; args.type = type; - stop_machine(__sm_arch_jump_label_transform, &args, NULL); + stop_machine_cpuslocked(__sm_arch_jump_label_transform, &args, NULL); } void arch_jump_label_transform_static(struct jump_entry *entry, --- a/arch/s390/kernel/kprobes.c +++ b/arch/s390/kernel/kprobes.c @@ -196,7 +196,7 @@ void arch_arm_kprobe(struct kprobe *p) { struct swap_insn_args args = {.p = p, .arm_kprobe = 1}; - stop_machine(swap_instruction, &args, NULL); + stop_machine_cpuslocked(swap_instruction, &args, NULL); } NOKPROBE_SYMBOL(arch_arm_kprobe); @@ -204,7 +204,7 @@ void arch_disarm_kprobe(struct kprobe *p { struct swap_insn_args args = {.p = p, .arm_kprobe = 0}; - stop_machine(swap_instruction, &args, NULL); + stop_machine_cpuslocked(swap_instruction, &args, NULL); } NOKPROBE_SYMBOL(arch_disarm_kprobe);
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