linux/net
Peter Zijlstra 700f9672c9 [IRDA]: Lockdep fix.
On Sat, 2006-11-18 at 16:12 +0300, Andrey Borzenkov wrote:

> =============================================
> [ INFO: possible recursive locking detected ]
> 2.6.19-rc5-2avb #2
> - ---------------------------------------------
> pppd/26425 is trying to acquire lock:
>  (&hashbin->hb_spinlock){....}, at: [<dfdea87a>] irlmp_slsap_inuse+0x5a/0x170
> [irda]
>
> but task is already holding lock:
>  (&hashbin->hb_spinlock){....}, at: [<dfdea857>] irlmp_slsap_inuse+0x37/0x170
> [irda]
>
> other info that might help us debug this:
> 1 lock held by pppd/26425:
>  #0:  (&hashbin->hb_spinlock){....}, at: [<dfdea857>]
> irlmp_slsap_inuse+0x37/0x170 [irda]
>
> stack backtrace:
>  [<c010413c>] dump_trace+0x1cc/0x200
>  [<c010418a>] show_trace_log_lvl+0x1a/0x30
>  [<c01047f2>] show_trace+0x12/0x20
>  [<c01048c9>] dump_stack+0x19/0x20
>  [<c01346ca>] __lock_acquire+0x8fa/0xc20
>  [<c0134d2d>] lock_acquire+0x5d/0x80
>  [<c02a851c>] _spin_lock+0x2c/0x40
>  [<dfdea87a>] irlmp_slsap_inuse+0x5a/0x170 [irda]
>  [<dfdebab2>] irlmp_open_lsap+0x62/0x180 [irda]
>  [<dfdf35d1>] irttp_open_tsap+0x181/0x230 [irda]
>  [<dfdc0c3d>] ircomm_open_tsap+0x5d/0xa0 [ircomm]
>  [<dfdc05d8>] ircomm_open+0xb8/0xd0 [ircomm]
>  [<dfdd0477>] ircomm_tty_open+0x4f7/0x570 [ircomm_tty]
>  [<c020bbe4>] tty_open+0x174/0x340
>  [<c016bd69>] chrdev_open+0x89/0x170
>  [<c0167bd6>] __dentry_open+0xa6/0x1d0
>  [<c0167da5>] nameidata_to_filp+0x35/0x40
>  [<c0167df9>] do_filp_open+0x49/0x50
>  [<c0167e47>] do_sys_open+0x47/0xd0
>  [<c0167f0c>] sys_open+0x1c/0x20
>  [<c010307d>] sysenter_past_esp+0x56/0x8d
>  [<b7f86410>] 0xb7f86410
>  =======================

The comment at the nesting lock says:

	/* Careful for priority inversions here !
	 * irlmp->links is never taken while another IrDA
	 * spinlock is held, so we are safe. Jean II */

So, under the assumption the author was right, it just needs a lockdep
annotation.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-11-21 17:33:01 -08:00
..
802 [TR]: endiannness annotations 2006-09-28 17:53:59 -07:00
8021q [PATCH] Finish annotations of struct vlan_ethhdr 2006-10-10 16:15:34 -07:00
appletalk [APPLETALK]: Fix potential OOPS in atalk_sendmsg(). 2006-10-30 15:24:34 -08:00
atm [ATM]: handle sysfs errors 2006-10-21 19:55:22 -07:00
ax25 [NET]: Conversions from kmalloc+memset to k(z|c)alloc. 2006-07-21 14:51:30 -07:00
bluetooth [BLUETOOTH]: Fix unaligned access in hci_send_to_sock. 2006-11-21 16:17:41 -08:00
bridge [NETFILTER]: silence a warning in ebtables 2006-11-01 18:07:27 -08:00
core [NET]: Set truesize in pskb_copy 2006-11-07 15:10:14 -08:00
dccp [DCCP]: fix printk format warnings 2006-10-30 15:24:37 -08:00
decnet [DECNET]: Endianess fixes (try #2) 2006-11-07 15:10:17 -08:00
econet [NET]: Conversions from kmalloc+memset to k(z|c)alloc. 2006-07-21 14:51:30 -07:00
ethernet [NET]: Annotate dst_ops protocol 2006-09-28 18:02:58 -07:00
ieee80211 [PATCH] ieee80211: don't flood log with errors 2006-10-31 22:15:38 -05:00
ipv4 [TCP]: Fix up sysctl_tcp_mem initialization. 2006-11-15 21:18:51 -08:00
ipv6 [IPV6] IP6TUNNEL: Add missing nf_reset() on input path. 2006-11-21 16:16:27 -08:00
ipx [IPX]: Annotate and fix IPX checksum 2006-11-05 14:11:25 -08:00
irda [IRDA]: Lockdep fix. 2006-11-21 17:33:01 -08:00
key IPsec: correct semantics for SELinux policy matching 2006-10-11 23:59:37 -07:00
lapb [LAPB]: Fix windowsize check 2006-08-05 21:15:58 -07:00
llc [LLC]: multicast receive device match 2006-08-13 18:56:26 -07:00
netfilter [NETFILTER]: Use pskb_trim in {ip,ip6,nfnetlink}_queue 2006-11-15 21:18:48 -08:00
netlabel [NETLABEL]: Fix build failure. 2006-11-05 16:44:06 -08:00
netlink [NET]: fix uaccess handling 2006-10-30 15:24:41 -08:00
netrom [NETROM] lockdep: fix false positive 2006-07-12 13:59:02 -07:00
packet [NET]: Fix sk->sk_filter field access 2006-09-22 15:18:47 -07:00
rose [ROSE] lockdep: fix false positive 2006-07-12 13:58:59 -07:00
rxrpc [PATCH] kmemdup: some users 2006-10-01 00:39:19 -07:00
sched [PKT_SCHED] sch_htb: Use hlist_del_init(). 2006-11-07 15:10:12 -08:00
sctp [SCTP]: Remove temporary associations from backlog and hash. 2006-10-30 18:55:11 -08:00
sunrpc [PATCH] sunrpc: add missing spin_unlock 2006-11-06 01:46:23 -08:00
tipc [TIPC] net/tipc/port.c: fix NULL dereference 2006-11-01 15:42:33 -08:00
unix [AF_UNIX]: Change max_dgram_qlen sysctl to __read_mostly 2006-09-22 15:18:42 -07:00
wanrouter [NET]: Conversions from kmalloc+memset to k(z|c)alloc. 2006-07-21 14:51:30 -07:00
x25 Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
xfrm [XFRM]: nlmsg length not computed correctly in the presence of subpolicies 2006-11-21 16:16:35 -08:00
compat.c [NET]: File descriptor loss while receiving SCM_RIGHTS 2006-10-11 23:59:48 -07:00
Kconfig [NETLABEL]: Fix build failure. 2006-11-05 16:44:06 -08:00
Makefile [NetLabel]: core NetLabel subsystem 2006-09-22 14:53:34 -07:00
nonet.c [PATCH] Make most file operations structs in fs/ const 2006-03-28 09:16:06 -08:00
socket.c [PATCH] file: modify struct fown_struct to use a struct pid 2006-10-02 07:57:14 -07:00
sysctl_net.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
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