With CONFIG_DEBUG_PREEMPT=y, I always see this warning: BUG: using smp_processor_id() in preemptible [00000000]
Fix the false warning by using raw_smp_processor_id(). Here vmbus_connect() sends a message to the host and waits for the host's response. The host will deliver the response message and an interrupt on CPU msg->target_vcpu, and later the interrupt handler will wake up vmbus_connect(). vmbus_connect() doesn't really have to run on the same cpu as CPU msg->target_vcpu, so it's safe to use raw_smp_processor_id() here. Signed-off-by: Dexuan Cui <[email protected]> Cc: [email protected] Cc: K. Y. Srinivasan <[email protected]> Cc: Haiyang Zhang <[email protected]> Cc: Stephen Hemminger <[email protected]> --- drivers/hv/connection.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index ced0418..c3b7040 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -119,8 +119,8 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, */ if (version >= VERSION_WIN8_1) { msg->target_vcpu = - hv_cpu_number_to_vp_number(smp_processor_id()); - vmbus_connection.connect_cpu = smp_processor_id(); + hv_cpu_number_to_vp_number(raw_smp_processor_id()); + vmbus_connection.connect_cpu = raw_smp_processor_id(); } else { msg->target_vcpu = 0; vmbus_connection.connect_cpu = 0; -- 2.7.4 _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
