diff options
Diffstat (limited to 'drivers/hv/hyperv_vmbus.h')
| -rw-r--r-- | drivers/hv/hyperv_vmbus.h | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index 12321b93a..718b5c72f 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -36,6 +36,11 @@ #define HV_UTIL_TIMEOUT 30 /* + * Timeout for guest-host handshake for services. + */ +#define HV_UTIL_NEGO_TIMEOUT 60 + +/* * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent * is set by CPUID(HVCPUID_VERSION_FEATURES). */ @@ -620,9 +625,21 @@ extern struct vmbus_channel_message_table_entry channel_message_table[CHANNELMSG_COUNT]; /* Free the message slot and signal end-of-message if required */ -static inline void vmbus_signal_eom(struct hv_message *msg) +static inline void vmbus_signal_eom(struct hv_message *msg, u32 old_msg_type) { - msg->header.message_type = HVMSG_NONE; + /* + * On crash we're reading some other CPU's message page and we need + * to be careful: this other CPU may already had cleared the header + * and the host may already had delivered some other message there. + * In case we blindly write msg->header.message_type we're going + * to lose it. We can still lose a message of the same type but + * we count on the fact that there can only be one + * CHANNELMSG_UNLOAD_RESPONSE and we don't care about other messages + * on crash. + */ + if (cmpxchg(&msg->header.message_type, old_msg_type, + HVMSG_NONE) != old_msg_type) + return; /* * Make sure the write to MessageType (ie set to @@ -667,8 +684,6 @@ void vmbus_disconnect(void); int vmbus_post_msg(void *buffer, size_t buflen); -void vmbus_set_event(struct vmbus_channel *channel); - void vmbus_on_event(unsigned long data); void vmbus_on_msg_dpc(unsigned long data); |