arm64: Prevent cpu hotplug rwsem recursion

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>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20170524081549.197070135@linutronix.de
This commit is contained in:
Thomas Gleixner 2017-05-24 10:15:37 +02:00
parent 2d1e38f566
commit c23a465625
2 changed files with 3 additions and 3 deletions

View File

@ -433,7 +433,6 @@ u32 aarch64_set_branch_offset(u32 insn, s32 offset);
bool aarch64_insn_hotpatch_safe(u32 old_insn, u32 new_insn);
int aarch64_insn_patch_text_nosync(void *addr, u32 insn);
int aarch64_insn_patch_text_sync(void *addrs[], u32 insns[], int cnt);
int aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt);
s32 aarch64_insn_adrp_get_offset(u32 insn);

View File

@ -255,6 +255,7 @@ static int __kprobes aarch64_insn_patch_text_cb(void *arg)
return ret;
}
static
int __kprobes aarch64_insn_patch_text_sync(void *addrs[], u32 insns[], int cnt)
{
struct aarch64_insn_patch patch = {
@ -267,7 +268,7 @@ int __kprobes aarch64_insn_patch_text_sync(void *addrs[], u32 insns[], int cnt)
if (cnt <= 0)
return -EINVAL;
return stop_machine(aarch64_insn_patch_text_cb, &patch,
return stop_machine_cpuslocked(aarch64_insn_patch_text_cb, &patch,
cpu_online_mask);
}