On Mon, Mar 11, 2013 at 10:55 AM, Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > On Mon, Mar 11, 2013 at 10:17:13AM +0800, Gao feng wrote: >> I get the below stack when I execute the shell program >> >> #!/bin/bash >> >> while :; >> do >> modprobe 8139too& >> rmmod 8139too& >> done >> >> I trust it is not the problem of 8139too, the other modules have the same problems too. >> Is this an already known problem? >> >> [ 53.328212] 8139too: 8139too Fast Ethernet driver 0.9.28 >> [ 53.368029] 8139too: module is already loaded >> [ 53.456339] 8139too: 8139too Fast Ethernet driver 0.9.28 >> [ 53.510611] 8139too: 8139too Fast Ethernet driver 0.9.28 >> [ 53.551713] ------------[ cut here ]------------ >> [ 53.551721] WARNING: at include/linux/kref.h:42 kobject_get+0x33/0x40() >> [ 53.551722] Hardware name: Bochs >> [ 53.551723] Modules linked in: 8139too(+) ebtable_nat ipt_MASQUERADE nf_conntrack_netbios_ns nf_conntrack_broadcast ip6table_mangle ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 iptable_nat nf_nat >> iptable_mangle nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack ebtable_filter bnep ebtables bluetooth rfkill ip6table_filter ip6_tables be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 >> cxgb3i cxgb3 mdio libcxgbi ib_iser rdma_cm ib_addr iw_cm ib_cm ib_sa ib_mad ib_core iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi snd_hda_intel snd_hda_codec snd_hwdep snd_seq snd_seq_device >> snd_pcm snd_page_alloc snd_timer microcode snd i2c_piix4 virtio_balloon 8139cp soundcore mii i2c_core uinput [last unloaded: 8139too] >> [ 53.551757] Pid: 1158, comm: modprobe Not tainted 3.6.10-4.fc18.x86_64 #1 > > Does this happen on a kernel.org kernel release? > > There's nothing I can do with a fedora kernel, sorry. > The comment says /** * kref_put - decrement refcount for object. * @kref: object. * @release: pointer to the function that will clean up the object when the * last reference to the object is released. * This pointer is required, and it is not acceptable to pass kfree * in as this function. If the caller does pass kfree to this * function, you will be publicly mocked mercilessly by the kref * maintainer, and anyone else who happens to notice it. You have * been warned. * * Decrement the refcount, and if 0, call release(). * Return 1 if the object was removed, otherwise return 0. Beware, if this * function returns 0, you still can not count on the kref from remaining in * memory. Only use the return value if you want to see if the kref is now * gone, not present. */ and the release callback is called too late since we have to /* remove the kobject from its kset's list */ even if refcount drops to zero. Hillf -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>