x86/hyper-v: Check cpumask_to_vpset() return value in hyperv_flush_tlb_others_ex()
authorVitaly Kuznetsov <vkuznets@redhat.com>
Mon, 9 Jul 2018 17:40:11 +0000 (19:40 +0200)
committerThomas Gleixner <tglx@linutronix.de>
Mon, 16 Jul 2018 09:19:48 +0000 (11:19 +0200)
Commit 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI
enlightenment") made cpumask_to_vpset() return '-1' when there is a CPU
with unknown VP index in the supplied set. This needs to be checked before
we pass 'nr_bank' to hypercall.

Fixes: 1268ed0c474a ("x86/hyper-v: Fix the circular dependency in IPI enlightenment")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: "Michael Kelley (EOSG)" <Michael.H.Kelley@microsoft.com>
Cc: devel@linuxdriverproject.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180709174012.17429-2-vkuznets@redhat.com
arch/x86/hyperv/mmu.c

index 0d90e515ec988480a4cd52dc8ff2f96ea3cc3aed..453d2355cd61dd46ddeadf7620a293b49918c715 100644 (file)
@@ -186,6 +186,8 @@ static u64 hyperv_flush_tlb_others_ex(const struct cpumask *cpus,
 
        flush->hv_vp_set.format = HV_GENERIC_SET_SPARSE_4K;
        nr_bank = cpumask_to_vpset(&(flush->hv_vp_set), cpus);
+       if (nr_bank < 0)
+               return U64_MAX;
 
        /*
         * We can flush not more than max_gvas with one hypercall. Flush the