Merge tag 'hyperv-fixes-signed-20210915' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux

Pull hyperv fixes from Wei Liu:

 - Fix kernel crash caused by uio driver (Vitaly Kuznetsov)

 - Remove on-stack cpumask from HV APIC code (Wei Liu)

* tag 'hyperv-fixes-signed-20210915' of git://git.kernel.org/pub/scm/linux/kernel/git/hyperv/linux:
  x86/hyperv: remove on-stack cpumask from hv_send_ipi_mask_allbutself
  asm-generic/hyperv: provide cpumask_to_vpset_noself
  Drivers: hv: vmbus: Fix kernel crash upon unbinding a device from uio_hv_generic driver

1 files changed, 19 insertions, 2 deletions

diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index c1ab6a6e72b5..d3eae6cdbacb 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -197,10 +197,12 @@ static inline int hv_cpu_number_to_vp_number(int cpu_number)
 	return hv_vp_index[cpu_number];
 }
 
-static inline int cpumask_to_vpset(struct hv_vpset *vpset,
-				    const struct cpumask *cpus)
+static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
+				    const struct cpumask *cpus,
+				    bool exclude_self)
 {
 	int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
+	int this_cpu = smp_processor_id();
 
 	/* valid_bank_mask can represent up to 64 banks */
 	if (hv_max_vp_index / 64 >= 64)
@@ -218,6 +220,8 @@ static inline int cpumask_to_vpset(struct hv_vpset *vpset,
 	 * Some banks may end up being empty but this is acceptable.
 	 */
 	for_each_cpu(cpu, cpus) {
+		if (exclude_self && cpu == this_cpu)
+			continue;
 		vcpu = hv_cpu_number_to_vp_number(cpu);
 		if (vcpu == VP_INVAL)
 			return -1;
@@ -232,6 +236,19 @@ static inline int cpumask_to_vpset(struct hv_vpset *vpset,
 	return nr_bank;
 }
 
+static inline int cpumask_to_vpset(struct hv_vpset *vpset,
+				    const struct cpumask *cpus)
+{
+	return __cpumask_to_vpset(vpset, cpus, false);
+}
+
+static inline int cpumask_to_vpset_noself(struct hv_vpset *vpset,
+				    const struct cpumask *cpus)
+{
+	WARN_ON_ONCE(preemptible());
+	return __cpumask_to_vpset(vpset, cpus, true);
+}
+
 void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
 bool hv_is_hyperv_initialized(void);
 bool hv_is_hibernation_supported(void);