From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, syzbot <syzkaller@googlegroups.com>,
Takashi Iwai <tiwai@suse.de>
Subject: [PATCH 3.18 22/28] ALSA: seq: Avoid invalid lockdep class warning
Date: Mon, 13 Nov 2017 13:55:16 +0100 [thread overview]
Message-ID: <20171113125402.849564257@linuxfoundation.org> (raw)
In-Reply-To: <20171113125400.803506921@linuxfoundation.org>
3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Takashi Iwai <tiwai@suse.de>
commit 3510c7aa069aa83a2de6dab2b41401a198317bdc upstream.
The recent fix for adding rwsem nesting annotation was using the given
"hop" argument as the lock subclass key. Although the idea itself
works, it may trigger a kernel warning like:
BUG: looking up invalid subclass: 8
....
since the lockdep has a smaller number of subclasses (8) than we
currently allow for the hops there (10).
The current definition is merely a sanity check for avoiding the too
deep delivery paths, and the 8 hops are already enough. So, as a
quick fix, just follow the max hops as same as the max lockdep
subclasses.
Fixes: 1f20f9ff57ca ("ALSA: seq: Fix nested rwsem annotation for lockdep splat")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/sound/seq_kernel.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/include/sound/seq_kernel.h
+++ b/include/sound/seq_kernel.h
@@ -55,7 +55,8 @@ typedef union snd_seq_timestamp snd_seq_
#define SNDRV_SEQ_DEFAULT_CLIENT_EVENTS 200
/* max delivery path length */
-#define SNDRV_SEQ_MAX_HOPS 10
+/* NOTE: this shouldn't be greater than MAX_LOCKDEP_SUBCLASSES */
+#define SNDRV_SEQ_MAX_HOPS 8
/* max size of event size */
#define SNDRV_SEQ_MAX_EVENT_LEN 0x3fffffff
next prev parent reply other threads:[~2017-11-13 12:56 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-11-13 12:54 [PATCH 3.18 00/28] 3.18.81-stable review Greg Kroah-Hartman
2017-11-13 12:54 ` [PATCH 3.18 01/28] video: fbdev: pmag-ba-fb: Remove bad `__init annotation Greg Kroah-Hartman
2017-11-13 12:54 ` [PATCH 3.18 02/28] xen/netback: set default upper limit of tx/rx queues to 8 Greg Kroah-Hartman
2017-11-13 12:54 ` [PATCH 3.18 03/28] ARM: dts: imx53-qsb-common: fix FEC pinmux config Greg Kroah-Hartman
2017-11-16 4:08 ` Patrick Brünn
2017-11-13 12:54 ` [PATCH 3.18 05/28] ARM: omap2plus_defconfig: Fix probe errors on UARTs 5 and 6 Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 06/28] iio: trigger: free trigger resource correctly Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 07/28] dt-bindings: Add LEGO MINDSTORMS EV3 compatible specification Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 08/28] dt-bindings: Add vendor prefix for LEGO Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 10/28] serial: sh-sci: Fix register offsets for the IRDA serial port Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 11/28] usb: hcd: initialize hcd->flags to 0 when rm hcd Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 12/28] IPsec: do not ignore crypto err in ah4 input Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 13/28] Input: mpr121 - handle multiple bits change of status register Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 14/28] Input: mpr121 - set missing event capability Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 15/28] IB/ipoib: Change list_del to list_del_init in the tx object Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 16/28] KEYS: trusted: sanitize all key material Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 17/28] KEYS: trusted: fix writing past end of buffer in trusted_read() Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 18/28] crypto: x86/sha1-mb - fix panic due to unaligned access Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 19/28] KEYS: fix NULL pointer dereference during ASN.1 parsing [ver #2] Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 20/28] ARM: 8720/1: ensure dump_instr() checks addr_limit Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 21/28] ALSA: seq: Fix OSS sysex delivery in OSS emulation Greg Kroah-Hartman
2017-11-13 12:55 ` Greg Kroah-Hartman [this message]
2017-11-13 12:55 ` [PATCH 3.18 23/28] MIPS: microMIPS: Fix incorrect mask in insn_table_MM Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 24/28] MIPS: Fix CM region target definitions Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 25/28] MIPS: AR7: Ensure that serial ports are properly set up Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 26/28] rbd: use GFP_NOIO for parent stat and data requests Greg Kroah-Hartman
2017-11-13 12:55 ` [PATCH 3.18 28/28] x86/oprofile/ppro: Do not use __this_cpu*() in preemptible context Greg Kroah-Hartman
2017-11-13 21:50 ` [PATCH 3.18 00/28] 3.18.81-stable review Shuah Khan
2017-11-14 7:43 ` Greg Kroah-Hartman
2017-11-13 22:27 ` Guenter Roeck
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