mei: amthif: discard not read messages

commit 9d04ee11db7bf0d848266cbfd7db336097a0e239 upstream.

When a message is received and amthif client is not in reading state
the message is ignored and left dangling in the queue. This may happen
after one of the amthif host connections is closed w/o completing the
reading. Another client will pick up a wrong message on next read
attempt which will lead to link reset.
To prevent this the driver has to properly discard the message when
amthif client is not in reading state.

Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/mei/amthif.c b/drivers/misc/mei/amthif.c
index cd0403f0926761ec7253c53e399844198728a3ea..e79c0371ee6ff7756a2dd6df206e079ccded2932 100644 (file)
--- a/drivers/misc/mei/amthif.c
+++ b/drivers/misc/mei/amthif.c
@@ -417,8 +417,10 @@ int mei_amthif_irq_read_msg(struct mei_cl *cl,
 
        dev = cl->dev;
 
-       if (dev->iamthif_state != MEI_IAMTHIF_READING)
+       if (dev->iamthif_state != MEI_IAMTHIF_READING) {
+               mei_irq_discard_msg(dev, mei_hdr);
                return 0;
+       }
 
        ret = mei_cl_irq_read_msg(cl, mei_hdr, cmpl_list);
        if (ret)

diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 44471edb62f7fcf48f75e704fed634187e441dfb..d1df797c7568dcf5650ab30e82552d482a87f550 100644 (file)
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -76,7 +76,6 @@ static inline int mei_cl_hbm_equal(struct mei_cl *cl,
  * @dev: mei device
  * @hdr: message header
  */
-static inline
 void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr)
 {
        /*

diff --git a/drivers/misc/mei/mei_dev.h b/drivers/misc/mei/mei_dev.h
index 4250555d5e72a2e29a5721de1fb0e790bc5747de..1b06e2fd6858ab2e3213ac63196a122a58e64eae 100644 (file)
--- a/drivers/misc/mei/mei_dev.h
+++ b/drivers/misc/mei/mei_dev.h
@@ -782,6 +782,8 @@ bool mei_hbuf_acquire(struct mei_device *dev);
 
 bool mei_write_is_idle(struct mei_device *dev);
 
+void mei_irq_discard_msg(struct mei_device *dev, struct mei_msg_hdr *hdr);
+
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 int mei_dbgfs_register(struct mei_device *dev, const char *name);
 void mei_dbgfs_deregister(struct mei_device *dev);