From 603c53e42adf5f2d29ffdd1ff1edda0c27e400df Mon Sep 17 00:00:00 2001
From: Alexander Usyskin <alexander.usyskin@intel.com>
Date: Sun, 7 Feb 2016 23:35:36 +0200
Subject: [PATCH] mei: discard replies from unconnected fixed address clients
A fixed address client in the FW doesn't have a notion of connection and
can send message after the file associated with it was already closed.
Silently discard such messages.
Add inline helpers to detect whether a message is hbm or intended for
a fixed address client
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>
---
drivers/misc/mei/interrupt.c | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)
diff --git a/drivers/misc/mei/interrupt.c b/drivers/misc/mei/interrupt.c
index 72806ef6efdd..06b744a503a3 100644
--- a/drivers/misc/mei/interrupt.c
+++ b/drivers/misc/mei/interrupt.c
@@ -239,6 +239,16 @@ static int mei_cl_irq_read(struct mei_cl *cl, struct mei_cl_cb *cb,
return 0;
}
+static inline bool hdr_is_hbm(struct mei_msg_hdr *mei_hdr)
+{
+ return mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0;
+}
+
+static inline bool hdr_is_fixed(struct mei_msg_hdr *mei_hdr)
+{
+ return mei_hdr->host_addr == 0 && mei_hdr->me_addr != 0;
+}
+
/**
* mei_irq_read_handler - bottom half read routine after ISR to
* handle the read processing.
@@ -280,7 +290,7 @@ int mei_irq_read_handler(struct mei_device *dev,
}
/* HBM message */
- if (mei_hdr->host_addr == 0 && mei_hdr->me_addr == 0) {
+ if (hdr_is_hbm(mei_hdr)) {
ret = mei_hbm_dispatch(dev, mei_hdr);
if (ret) {
dev_dbg(dev->dev, "mei_hbm_dispatch failed ret = %d\n",
@@ -300,6 +310,14 @@ int mei_irq_read_handler(struct mei_device *dev,
/* if no recipient cl was found we assume corrupted header */
if (&cl->link == &dev->file_list) {
+ /* A message for not connected fixed address clients
+ * should be silently discarded
+ */
+ if (hdr_is_fixed(mei_hdr)) {
+ mei_irq_discard_msg(dev, mei_hdr);
+ ret = 0;
+ goto reset_slots;
+ }
dev_err(dev->dev, "no destination client found 0x%08X\n",
dev->rd_msg_hdr);
ret = -EBADMSG;
--
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