linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Konstantin Khlebnikov <khlebnikov@openvz.org>
To: linux-kernel@vger.kernel.org
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>, linux-media@vger.kernel.org
Subject: [PATCH 06/12] media/rc: fix oops on unloading module rc-core
Date: Fri, 14 Dec 2012 15:02:48 +0400	[thread overview]
Message-ID: <20121214110248.11019.36202.stgit@zurg> (raw)
In-Reply-To: <20121214110229.11019.63713.stgit@zurg>

During modiles initialization rc-core schedules work which calls
request_module() several times to load ir-*-decoder modules, but
it does not wait or cancel this work on module unloading.

rc-core should use request_module_nowait() instead, because it
anyway cannot load modules synchronously or cancel/wait pending
work on unloading, because this leads to deadlock on modules_mutex
between several "modprobe" processes.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: linux-media@vger.kernel.org
---
 drivers/media/rc/ir-raw.c       |   17 +----------------
 drivers/media/rc/rc-core-priv.h |   16 ++++++++--------
 2 files changed, 9 insertions(+), 24 deletions(-)

diff --git a/drivers/media/rc/ir-raw.c b/drivers/media/rc/ir-raw.c
index 97dc8d1..17c94be 100644
--- a/drivers/media/rc/ir-raw.c
+++ b/drivers/media/rc/ir-raw.c
@@ -31,11 +31,6 @@ static DEFINE_MUTEX(ir_raw_handler_lock);
 static LIST_HEAD(ir_raw_handler_list);
 static u64 available_protocols;
 
-#ifdef MODULE
-/* Used to load the decoders */
-static struct work_struct wq_load;
-#endif
-
 static int ir_raw_event_thread(void *data)
 {
 	struct ir_raw_event ev;
@@ -347,8 +342,7 @@ void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler)
 }
 EXPORT_SYMBOL(ir_raw_handler_unregister);
 
-#ifdef MODULE
-static void init_decoders(struct work_struct *work)
+void ir_raw_init(void)
 {
 	/* Load the decoder modules */
 
@@ -365,12 +359,3 @@ static void init_decoders(struct work_struct *work)
 	   it is needed to change the CONFIG_MODULE test at rc-core.h
 	 */
 }
-#endif
-
-void ir_raw_init(void)
-{
-#ifdef MODULE
-	INIT_WORK(&wq_load, init_decoders);
-	schedule_work(&wq_load);
-#endif
-}
diff --git a/drivers/media/rc/rc-core-priv.h b/drivers/media/rc/rc-core-priv.h
index 96f0a8b..5d87287 100644
--- a/drivers/media/rc/rc-core-priv.h
+++ b/drivers/media/rc/rc-core-priv.h
@@ -165,56 +165,56 @@ void ir_raw_init(void);
 
 /* from ir-nec-decoder.c */
 #ifdef CONFIG_IR_NEC_DECODER_MODULE
-#define load_nec_decode()	request_module("ir-nec-decoder")
+#define load_nec_decode()	request_module_nowait("ir-nec-decoder")
 #else
 static inline void load_nec_decode(void) { }
 #endif
 
 /* from ir-rc5-decoder.c */
 #ifdef CONFIG_IR_RC5_DECODER_MODULE
-#define load_rc5_decode()	request_module("ir-rc5-decoder")
+#define load_rc5_decode()	request_module_nowait("ir-rc5-decoder")
 #else
 static inline void load_rc5_decode(void) { }
 #endif
 
 /* from ir-rc6-decoder.c */
 #ifdef CONFIG_IR_RC6_DECODER_MODULE
-#define load_rc6_decode()	request_module("ir-rc6-decoder")
+#define load_rc6_decode()	request_module_nowait("ir-rc6-decoder")
 #else
 static inline void load_rc6_decode(void) { }
 #endif
 
 /* from ir-jvc-decoder.c */
 #ifdef CONFIG_IR_JVC_DECODER_MODULE
-#define load_jvc_decode()	request_module("ir-jvc-decoder")
+#define load_jvc_decode()	request_module_nowait("ir-jvc-decoder")
 #else
 static inline void load_jvc_decode(void) { }
 #endif
 
 /* from ir-sony-decoder.c */
 #ifdef CONFIG_IR_SONY_DECODER_MODULE
-#define load_sony_decode()	request_module("ir-sony-decoder")
+#define load_sony_decode()	request_module_nowait("ir-sony-decoder")
 #else
 static inline void load_sony_decode(void) { }
 #endif
 
 /* from ir-sanyo-decoder.c */
 #ifdef CONFIG_IR_SANYO_DECODER_MODULE
-#define load_sanyo_decode()	request_module("ir-sanyo-decoder")
+#define load_sanyo_decode()	request_module_nowait("ir-sanyo-decoder")
 #else
 static inline void load_sanyo_decode(void) { }
 #endif
 
 /* from ir-mce_kbd-decoder.c */
 #ifdef CONFIG_IR_MCE_KBD_DECODER_MODULE
-#define load_mce_kbd_decode()	request_module("ir-mce_kbd-decoder")
+#define load_mce_kbd_decode()	request_module_nowait("ir-mce_kbd-decoder")
 #else
 static inline void load_mce_kbd_decode(void) { }
 #endif
 
 /* from ir-lirc-codec.c */
 #ifdef CONFIG_IR_LIRC_CODEC_MODULE
-#define load_lirc_codec()	request_module("ir-lirc-codec")
+#define load_lirc_codec()	request_module_nowait("ir-lirc-codec")
 #else
 static inline void load_lirc_codec(void) { }
 #endif


  parent reply	other threads:[~2012-12-14 11:02 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-14 11:02 [PATCH 01/12] tools/testing/modules: introduce test which loads/unloads random modules Konstantin Khlebnikov
2012-12-14 11:02 ` [PATCH 02/12] driver core: add debug-objects debug for device-drivers Konstantin Khlebnikov
2012-12-14 11:02 ` [PATCH 03/12] mISDN: fix race in timer canceling on module unloading Konstantin Khlebnikov
2012-12-14 18:16   ` David Miller
2012-12-14 11:02 ` [PATCH 04/12] pps: pps_parport: fix oops " Konstantin Khlebnikov
2012-12-14 11:02 ` [PATCH 05/12] staging: vme_pio2: " Konstantin Khlebnikov
2012-12-17 12:01   ` Martyn Welch
2012-12-14 11:02 ` Konstantin Khlebnikov [this message]
2012-12-14 11:02 ` [PATCH 07/12] stmmac: fix platform driver unregistering Konstantin Khlebnikov
2012-12-14 18:16   ` David Miller
2012-12-14 11:02 ` [PATCH 08/12] bonding: do not cancel works in bond_uninit() Konstantin Khlebnikov
2012-12-14 18:16   ` David Miller
2012-12-14 11:02 ` [PATCH 09/12] pps: fix device destruction ordering Konstantin Khlebnikov
2012-12-14 11:03 ` [PATCH 10/12] mac802154: fix destructon ordering for ieee802154 devices Konstantin Khlebnikov
2012-12-14 18:16   ` David Miller
2012-12-14 11:03 ` [PATCH 11/12] firmware/dmi-sysfs: fix sysfs warning on module unload Konstantin Khlebnikov
2012-12-14 11:03 ` [PATCH 12/12] edac: fix kernel panic on module unloading Konstantin Khlebnikov
2012-12-14 11:26   ` Alan Cox
2012-12-14 11:50     ` Borislav Petkov
2012-12-14 11:55     ` Konstantin Khlebnikov
2012-12-14 13:26       ` Alan Cox
2012-12-15 17:53   ` Borislav Petkov

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20121214110248.11019.36202.stgit@zurg \
    --to=khlebnikov@openvz.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-media@vger.kernel.org \
    --cc=mchehab@redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).