Commit 9925cc13 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux 

Pull arm64 fixes from Will Deacon:
 "Just a couple of stragglers here:

   - fix an issue migrating interrupts on CPU hotplug
   - fix a potential information leak of TLS registers across an exec
     (Nathan has sent a corresponding patch for arch/arm/ to rmk)"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: flush TLS registers during exec
  arm64: use irq_set_affinity with force=false when migrating irqs
parents 753a6cb7 eb35bdd7

arch/arm64/kernel/irq.c

+4 −8
Original line number Diff line number Diff line
@@ -97,19 +97,15 @@ static bool migrate_one_irq(struct irq_desc *desc) 
	if (irqd_is_per_cpu(d) || !cpumask_test_cpu(smp_processor_id(), affinity))

		return false;



	if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids)

	if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {

		affinity = cpu_online_mask;

		ret = true;

	}



	/*

	 * when using forced irq_set_affinity we must ensure that the cpu

	 * being offlined is not present in the affinity mask, it may be

	 * selected as the target CPU otherwise

	 */

	affinity = cpu_online_mask;

	c = irq_data_get_irq_chip(d);

	if (!c->irq_set_affinity)

		pr_debug("IRQ%u: unable to set affinity\n", d->irq);

	else if (c->irq_set_affinity(d, affinity, true) == IRQ_SET_MASK_OK && ret)

	else if (c->irq_set_affinity(d, affinity, false) == IRQ_SET_MASK_OK && ret)

		cpumask_copy(d->affinity, affinity);



	return ret;

arch/arm64/kernel/process.c

+18 −0
Original line number Diff line number Diff line
@@ -230,9 +230,27 @@ void exit_thread(void) 
{

}



static void tls_thread_flush(void)

{

	asm ("msr tpidr_el0, xzr");



	if (is_compat_task()) {

		current->thread.tp_value = 0;



		/*

		 * We need to ensure ordering between the shadow state and the

		 * hardware state, so that we don't corrupt the hardware state

		 * with a stale shadow state during context switch.

		 */

		barrier();

		asm ("msr tpidrro_el0, xzr");

	}

}



void flush_thread(void)

{

	fpsimd_flush_thread();

	tls_thread_flush();

	flush_ptrace_hw_breakpoint(current);

}

arch/arm64/kernel/sys_compat.c

+6 −0
Original line number Diff line number Diff line
@@ -79,6 +79,12 @@ long compat_arm_syscall(struct pt_regs *regs) 


	case __ARM_NR_compat_set_tls:

		current->thread.tp_value = regs->regs[0];



		/*

		 * Protect against register corruption from context switch.

		 * See comment in tls_thread_flush.

		 */

		barrier();

		asm ("msr tpidrro_el0, %0" : : "r" (regs->regs[0]));

		return 0;

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