Most recent kernel where this bug did not occur: 2.6.14.5
Distribution: fedora core 4 with updates
Hardware Environment: amd64
Software Environment: ppp 2.4.2-7
Problem Description: when use ppp with wvdial ppp doesn't work and in dmesg
CSLIP: code copyright 1989 Regents of the University of California
PPP generic driver version 2.4.2
skb_over_panic: text:ffffffff88052ce1 len:1 put:1 head:ffff81003e875000
data:ffff81013e875002 tail:ffff81013e875003 end:ffff81003e875600
dev:<NULL>----------- [cut here ] --------- [please bite here ] ---------
Kernel BUG at net/core/skbuff.c:94
invalid operand: 0000 [1]
CPU 0
Modules linked in: ppp_async ppp_generic slhc ohci_hcd ehci_hcd 8139too ne2k_pci
8390 usbcore sata_nv libata
Pid: 3, comm: events/0 Not tainted 2.6.15 #18
RIP: 0010:[<ffffffff802618fb>] <ffffffff802618fb>{skb_over_panic+75}
RSP: 0018:ffff81003fea9de8  EFLAGS: 00010092
RAX: 000000000000009a RBX: ffff81013e875002 RCX: ffffffff80311290
RDX: ffffffff80311290 RSI: 0000000000000001 RDI: ffff81003f978240
RBP: ffff810039b09800 R08: 0000000036357068 R09: ffff810037d410c0
R10: 0000000000000010 R11: 0000000000000010 R12: ffff8100396265d6
R13: ffff8100396261d6 R14: 0000000000000001 R15: 0000000000000003
FS:  00002aaaaaac19c0(0000) GS:ffffffff8039f800(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000003a30691c30 CR3: 0000000039ae9000 CR4: 00000000000006e0
Process events/0 (pid: 3, threadinfo ffff81003fea8000, task ffff81003ff80710)
Stack: ffff81013e875003 ffff81003e875600 ffffffff802d8be3 ffff81013e875003
       ffff81013e875003 ffffffff88052ce9 0000000000000b2b ffff810039626000
       0000000000000202 ffff810039626000
Call Trace:<ffffffff88052ce9>{:ppp_async:ppp_asynctty_receive+496}
       <ffffffff80137db1>{worker_thread+0} <ffffffff80227e99>{flush_to_ldisc+192}
       <ffffffff80137f08>{worker_thread+343}
<ffffffff801280d1>{default_wake_function+0}
       <ffffffff80137db1>{worker_thread+0} <ffffffff8013b2c2>{kthread+205}
       <ffffffff8010df5a>{child_rip+8} <ffffffff8013b1f5>{kthread+0}
       <ffffffff8010df52>{child_rip+0}

Code: 0f 0b 68 16 4f 2e 80 c2 5e 00 48 83 c4 28 c3 51 49 89 d2 48
RIP <ffffffff802618fb>{skb_over_panic+75} RSP <ffff81003fea9de8>
 <6>

Steps to reproduce: use wvdial with ppp and kernel 2.6.15, with 2.6.14.5 it work
correctly