hv: allocate synic pages for all present CPUs

BugLink: http://bugs.launchpad.net/bugs/1673538
commit 421b8f20d3c381b215f988b42428f56fc3b82405 upstream.

It may happen that not all CPUs are online when we do hv_synic_alloc() and
in case more CPUs come online later we may try accessing these allocated
structures.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index 60db5ff43a03f5c1f59e7c340b970ebe630c0a8f..a908064e63290c65fdd00529c2fa845afdf38ed3 100644 (file)
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -420,7 +420,7 @@ int hv_synic_alloc(void)
                goto err;
        }
 
-       for_each_online_cpu(cpu) {
+       for_each_present_cpu(cpu) {
                hv_context.event_dpc[cpu] = kmalloc(size, GFP_ATOMIC);
                if (hv_context.event_dpc[cpu] == NULL) {
                        pr_err("Unable to allocate event dpc\n");
@@ -491,7 +491,7 @@ void hv_synic_free(void)
        int cpu;
 
        kfree(hv_context.hv_numa_map);
-       for_each_online_cpu(cpu)
+       for_each_present_cpu(cpu)
                hv_synic_free_cpu(cpu);
 }