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authorThomas Gleixner <tglx@linutronix.de>2017-05-24 10:15:37 +0200
committerThomas Gleixner <tglx@linutronix.de>2017-05-26 10:10:45 +0200
commitc23a465625e287c4deba0fdf5e8adc59cfd2a0b7 (patch)
tree11235b5ba8e8e602f37676e4f9ea3187118293a6
parent2d1e38f56622b9bb5af85be63c1052c056f5c677 (diff)
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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
-rw-r--r--arch/arm64/include/asm/insn.h1
-rw-r--r--arch/arm64/kernel/insn.c5
2 files changed, 3 insertions, 3 deletions
diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
index 29cb2ca756f6..4214c38d016b 100644
--- a/arch/arm64/include/asm/insn.h
+++ b/arch/arm64/include/asm/insn.h
@@ -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);
diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c
index b884a926a632..cd872133e88e 100644
--- a/arch/arm64/kernel/insn.c
+++ b/arch/arm64/kernel/insn.c
@@ -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 = {
@@ -267,8 +268,8 @@ 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,
- cpu_online_mask);
+ return stop_machine_cpuslocked(aarch64_insn_patch_text_cb, &patch,
+ cpu_online_mask);
}
int __kprobes aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt)