Commit b9830d12 authored by K. Y. Srinivasan's avatar K. Y. Srinivasan Committed by Greg Kroah-Hartman
Browse files

Drivers: hv: util: Pass the channel information during the init call 



Pass the channel information to the util drivers that need to defer
reading the channel while they are processing a request. This would address
the following issue reported by Vitaly:

Commit 3cace4a6 ("Drivers: hv: utils: run polling callback always in
interrupt context") removed direct *_transaction.state = HVUTIL_READY
assignments from *_handle_handshake() functions introducing the following
race: if a userspace daemon connects before we get first non-negotiation
request from the server hv_poll_channel() won't set transaction state to
HVUTIL_READY as (!channel) condition will fail, we set it to non-NULL on
the first real request from the server.

Signed-off-by: default avatarK. Y. Srinivasan <kys@microsoft.com>
Reported-by: default avatarVitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent d452ab7b

drivers/hv/hv_fcopy.c

+1 −1
Original line number Diff line number Diff line
@@ -251,7 +251,6 @@ void hv_fcopy_onchannelcallback(void *context) 
		 */



		fcopy_transaction.recv_len = recvlen;

		fcopy_transaction.recv_channel = channel;

		fcopy_transaction.recv_req_id = requestid;

		fcopy_transaction.fcopy_msg = fcopy_msg;
@@ -317,6 +316,7 @@ static void fcopy_on_reset(void) 
int hv_fcopy_init(struct hv_util_service *srv)

{

	recv_buffer = srv->recv_buffer;

	fcopy_transaction.recv_channel = srv->channel;



	/*

	 * When this driver loads, the user level daemon that

drivers/hv/hv_kvp.c

+1 −1
Original line number Diff line number Diff line
@@ -639,7 +639,6 @@ void hv_kvp_onchannelcallback(void *context) 
			 */



			kvp_transaction.recv_len = recvlen;

			kvp_transaction.recv_channel = channel;

			kvp_transaction.recv_req_id = requestid;

			kvp_transaction.kvp_msg = kvp_msg;
@@ -688,6 +687,7 @@ int 
hv_kvp_init(struct hv_util_service *srv)

{

	recv_buffer = srv->recv_buffer;

	kvp_transaction.recv_channel = srv->channel;



	/*

	 * When this driver loads, the user level daemon that

drivers/hv/hv_snapshot.c

+1 −1
Original line number Diff line number Diff line
@@ -263,7 +263,6 @@ void hv_vss_onchannelcallback(void *context) 
			 */



			vss_transaction.recv_len = recvlen;

			vss_transaction.recv_channel = channel;

			vss_transaction.recv_req_id = requestid;

			vss_transaction.msg = (struct hv_vss_msg *)vss_msg;
@@ -337,6 +336,7 @@ hv_vss_init(struct hv_util_service *srv) 
		return -ENOTSUPP;

	}

	recv_buffer = srv->recv_buffer;

	vss_transaction.recv_channel = srv->channel;



	/*

	 * When this driver loads, the user level daemon that

drivers/hv/hv_util.c

+1 −0
Original line number Diff line number Diff line
@@ -322,6 +322,7 @@ static int util_probe(struct hv_device *dev, 
	srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL);

	if (!srv->recv_buffer)

		return -ENOMEM;

	srv->channel = dev->channel;

	if (srv->util_init) {

		ret = srv->util_init(srv);

		if (ret) {

include/linux/hyperv.h

+1 −0
Original line number Diff line number Diff line
@@ -1251,6 +1251,7 @@ u64 hv_do_hypercall(u64 control, void *input, void *output); 


struct hv_util_service {

	u8 *recv_buffer;

	void *channel;

	void (*util_cb)(void *);

	int (*util_init)(struct hv_util_service *);

	void (*util_deinit)(void);

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