linux-stable.git/drivers/net/dummy.c, branch linux-3.4.y Linux kernel stable tree dummy: fix oops when loading the dummy failed 2013-07-28T23:26:07+00:00 dingtianhong dingtianhong@huawei.com 2013-07-11T11:04:02+00:00 7f6d8ea02c762b788ba38d4f084ad18b6e569813 [ Upstream commit 2c8a01894a12665d8059fad8f0a293c98a264121 ] We rename the dummy in modprobe.conf like this: install dummy0 /sbin/modprobe -o dummy0 --ignore-install dummy install dummy1 /sbin/modprobe -o dummy1 --ignore-install dummy We got oops when we run the command: modprobe dummy0 modprobe dummy1 ------------[ cut here ]------------ [ 3302.187584] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 3302.195411] IP: [<ffffffff813fe62a>] __rtnl_link_unregister+0x9a/0xd0 [ 3302.201844] PGD 85c94a067 PUD 8517bd067 PMD 0 [ 3302.206305] Oops: 0002 [#1] SMP [ 3302.299737] task: ffff88105ccea300 ti: ffff880eba4a0000 task.ti: ffff880eba4a0000 [ 3302.307186] RIP: 0010:[<ffffffff813fe62a>] [<ffffffff813fe62a>] __rtnl_link_unregister+0x9a/0xd0 [ 3302.316044] RSP: 0018:ffff880eba4a1dd8 EFLAGS: 00010246 [ 3302.321332] RAX: 0000000000000000 RBX: ffffffff81a9d738 RCX: 0000000000000002 [ 3302.328436] RDX: 0000000000000000 RSI: ffffffffa04d602c RDI: ffff880eba4a1dd8 [ 3302.335541] RBP: ffff880eba4a1e18 R08: dead000000200200 R09: dead000000100100 [ 3302.342644] R10: 0000000000000080 R11: 0000000000000003 R12: ffffffff81a9d788 [ 3302.349748] R13: ffffffffa04d7020 R14: ffffffff81a9d670 R15: ffff880eba4a1dd8 [ 3302.364910] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3302.370630] CR2: 0000000000000008 CR3: 000000085e15e000 CR4: 00000000000427e0 [ 3302.377734] DR0: 0000000000000003 DR1: 00000000000000b0 DR2: 0000000000000001 [ 3302.384838] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 3302.391940] Stack: [ 3302.393944] ffff880eba4a1dd8 ffff880eba4a1dd8 ffff880eba4a1e18 ffffffffa04d70c0 [ 3302.401350] 00000000ffffffef ffffffffa01a8000 0000000000000000 ffffffff816111c8 [ 3302.408758] ffff880eba4a1e48 ffffffffa01a80be ffff880eba4a1e48 ffffffffa04d70c0 [ 3302.416164] Call Trace: [ 3302.418605] [<ffffffffa01a8000>] ? 0xffffffffa01a7fff [ 3302.423727] [<ffffffffa01a80be>] dummy_init_module+0xbe/0x1000 [dummy0] [ 3302.430405] [<ffffffffa01a8000>] ? 0xffffffffa01a7fff [ 3302.435535] [<ffffffff81000322>] do_one_initcall+0x152/0x1b0 [ 3302.441263] [<ffffffff810ab24b>] do_init_module+0x7b/0x200 [ 3302.446824] [<ffffffff810ad3d2>] load_module+0x4e2/0x530 [ 3302.452215] [<ffffffff8127ae40>] ? ddebug_dyndbg_boot_param_cb+0x60/0x60 [ 3302.458979] [<ffffffff810ad5f1>] SyS_init_module+0xd1/0x130 [ 3302.464627] [<ffffffff814b9652>] system_call_fastpath+0x16/0x1b [ 3302.490090] RIP [<ffffffff813fe62a>] __rtnl_link_unregister+0x9a/0xd0 [ 3302.496607] RSP <ffff880eba4a1dd8> [ 3302.500084] CR2: 0000000000000008 [ 3302.503466] ---[ end trace 8342d49cd49f78ed ]--- The reason is that when loading dummy, if __rtnl_link_register() return failed, the init_module should return and avoid take the wrong path. Signed-off-by: Tan Xiaojun <tanxiaojun@huawei.com> Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 2c8a01894a12665d8059fad8f0a293c98a264121 ]

We rename the dummy in modprobe.conf like this:

install dummy0 /sbin/modprobe -o dummy0 --ignore-install dummy
install dummy1 /sbin/modprobe -o dummy1 --ignore-install dummy

We got oops when we run the command:

modprobe dummy0
modprobe dummy1

------------[ cut here ]------------

[ 3302.187584] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[ 3302.195411] IP: [<ffffffff813fe62a>] __rtnl_link_unregister+0x9a/0xd0
[ 3302.201844] PGD 85c94a067 PUD 8517bd067 PMD 0
[ 3302.206305] Oops: 0002 [#1] SMP
[ 3302.299737] task: ffff88105ccea300 ti: ffff880eba4a0000 task.ti: ffff880eba4a0000
[ 3302.307186] RIP: 0010:[<ffffffff813fe62a>]  [<ffffffff813fe62a>] __rtnl_link_unregister+0x9a/0xd0
[ 3302.316044] RSP: 0018:ffff880eba4a1dd8  EFLAGS: 00010246
[ 3302.321332] RAX: 0000000000000000 RBX: ffffffff81a9d738 RCX: 0000000000000002
[ 3302.328436] RDX: 0000000000000000 RSI: ffffffffa04d602c RDI: ffff880eba4a1dd8
[ 3302.335541] RBP: ffff880eba4a1e18 R08: dead000000200200 R09: dead000000100100
[ 3302.342644] R10: 0000000000000080 R11: 0000000000000003 R12: ffffffff81a9d788
[ 3302.349748] R13: ffffffffa04d7020 R14: ffffffff81a9d670 R15: ffff880eba4a1dd8
[ 3302.364910] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3302.370630] CR2: 0000000000000008 CR3: 000000085e15e000 CR4: 00000000000427e0
[ 3302.377734] DR0: 0000000000000003 DR1: 00000000000000b0 DR2: 0000000000000001
[ 3302.384838] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 3302.391940] Stack:
[ 3302.393944]  ffff880eba4a1dd8 ffff880eba4a1dd8 ffff880eba4a1e18 ffffffffa04d70c0
[ 3302.401350]  00000000ffffffef ffffffffa01a8000 0000000000000000 ffffffff816111c8
[ 3302.408758]  ffff880eba4a1e48 ffffffffa01a80be ffff880eba4a1e48 ffffffffa04d70c0
[ 3302.416164] Call Trace:
[ 3302.418605]  [<ffffffffa01a8000>] ? 0xffffffffa01a7fff
[ 3302.423727]  [<ffffffffa01a80be>] dummy_init_module+0xbe/0x1000 [dummy0]
[ 3302.430405]  [<ffffffffa01a8000>] ? 0xffffffffa01a7fff
[ 3302.435535]  [<ffffffff81000322>] do_one_initcall+0x152/0x1b0
[ 3302.441263]  [<ffffffff810ab24b>] do_init_module+0x7b/0x200
[ 3302.446824]  [<ffffffff810ad3d2>] load_module+0x4e2/0x530
[ 3302.452215]  [<ffffffff8127ae40>] ? ddebug_dyndbg_boot_param_cb+0x60/0x60
[ 3302.458979]  [<ffffffff810ad5f1>] SyS_init_module+0xd1/0x130
[ 3302.464627]  [<ffffffff814b9652>] system_call_fastpath+0x16/0x1b
[ 3302.490090] RIP  [<ffffffff813fe62a>] __rtnl_link_unregister+0x9a/0xd0
[ 3302.496607]  RSP <ffff880eba4a1dd8>
[ 3302.500084] CR2: 0000000000000008
[ 3302.503466] ---[ end trace 8342d49cd49f78ed ]---

The reason is that when loading dummy, if __rtnl_link_register() return failed,
the init_module should return and avoid take the wrong path.

Signed-off-by: Tan Xiaojun <tanxiaojun@huawei.com>
Signed-off-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dummy: fix rcu_sched self-detected stalls 2012-07-16T16:03:47+00:00 Eric Dumazet edumazet@google.com 2012-06-10T21:11:57+00:00 09838df9d2ff31252a69a8393ea96a9734eba7e8 [ Upstream commit 16b0dc29c1af9df341428f4c49ada4f626258082 ] Trying to "modprobe dummy numdummies=30000" triggers : INFO: rcu_sched self-detected stall on CPU { 8} (t=60000 jiffies) After this splat, RTNL is locked and reboot is needed. We must call cond_resched() to avoid this, even holding RTNL. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 16b0dc29c1af9df341428f4c49ada4f626258082 ]

Trying to "modprobe dummy numdummies=30000" triggers :

INFO: rcu_sched self-detected stall on CPU { 8} (t=60000 jiffies)

After this splat, RTNL is locked and reboot is needed.

We must call cond_resched() to avoid this, even holding RTNL.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dummy: Add ndo_uninit(). 2012-04-17T03:56:36+00:00 Hiroaki SHIMODA shimoda.hiroaki@gmail.com 2012-04-15T13:26:01+00:00 890fdf2a0cb88202d1427589db2cf29c1bdd3c1d In register_netdevice(), when ndo_init() is successful and later some error occurred, ndo_uninit() will be called. So dummy deivce is desirable to implement ndo_uninit() method to free percpu stats for this case. And, ndo_uninit() is also called along with dev->destructor() when device is unregistered, so in order to prevent dev->dstats from being freed twice, dev->destructor is modified to free_netdev(). Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
In register_netdevice(), when ndo_init() is successful and later
some error occurred, ndo_uninit() will be called.
So dummy deivce is desirable to implement ndo_uninit() method
to free percpu stats for this case.
And, ndo_uninit() is also called along with dev->destructor() when
device is unregistered, so in order to prevent dev->dstats from
being freed twice, dev->destructor is modified to free_netdev().

Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: use eth_hw_addr_random() and reset addr_assign_type 2012-02-15T20:34:17+00:00 Danny Kukawka danny.kukawka@bisect.de 2012-02-15T06:45:40+00:00 7ce5d222190cb3ce3ae88bafde7c4fa52a5103e0 Use eth_hw_addr_random() instead of calling random_ether_addr() to set addr_assign_type correctly to NET_ADDR_RANDOM. Reset the state to NET_ADDR_PERM as soon as the MAC get changed via .ndo_set_mac_address. v2: adapt to renamed eth_hw_addr_random() Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de> Signed-off-by: David S. Miller <davem@davemloft.net> 
Use eth_hw_addr_random() instead of calling random_ether_addr()
to set addr_assign_type correctly to NET_ADDR_RANDOM.

Reset the state to NET_ADDR_PERM as soon as the MAC get
changed via .ndo_set_mac_address.

v2: adapt to renamed eth_hw_addr_random()

Signed-off-by: Danny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: remove NETIF_F_NO_CSUM feature bit 2011-11-16T22:43:12+00:00 Michał Mirosław mirq-linux@rere.qmqm.pl 2011-11-15T15:29:55+00:00 34324dc2bf27c1773045fea63cb11f7e2a6ad2b9 Only distinct use is checking if NETIF_F_NOCACHE_COPY should be enabled by default. The check heuristics is altered a bit here, so it hits other people than before. The default shouldn't be trusted for performance-critical cases anyway. For all other uses NETIF_F_NO_CSUM is equivalent to NETIF_F_HW_CSUM. Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net> 
Only distinct use is checking if NETIF_F_NOCACHE_COPY should be
enabled by default. The check heuristics is altered a bit here,
so it hits other people than before. The default shouldn't be
trusted for performance-critical cases anyway.

For all other uses NETIF_F_NO_CSUM is equivalent to NETIF_F_HW_CSUM.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: remove use of ndo_set_multicast_list in drivers 2011-08-18T03:22:03+00:00 Jiri Pirko jpirko@redhat.com 2011-08-16T06:29:01+00:00 afc4b13df143122f99a0eb10bfefb216c2806de0 replace it by ndo_set_rx_mode Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
replace it by ndo_set_rx_mode

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: call dev_alloc_name from register_netdevice 2011-05-05T17:57:45+00:00 Jiri Pirko jpirko@redhat.com 2011-04-30T01:21:32+00:00 1c5cae815d19ffe02bdfda1260949ef2b1806171 Force dev_alloc_name() to be called from register_netdevice() by dev_get_valid_name(). That allows to remove multiple explicit dev_alloc_name() calls. The possibility to call dev_alloc_name in advance remains. This also fixes veth creation regresion caused by 84c49d8c3e4abefb0a41a77b25aa37ebe8d6b743 Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Force dev_alloc_name() to be called from register_netdevice() by
dev_get_valid_name(). That allows to remove multiple explicit
dev_alloc_name() calls.

The possibility to call dev_alloc_name in advance remains.

This also fixes veth creation regresion caused by
84c49d8c3e4abefb0a41a77b25aa37ebe8d6b743

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
dummy: percpu stats and lockless xmit 2010-09-29T20:23:30+00:00 Eric Dumazet eric.dumazet@gmail.com 2010-09-27T20:50:33+00:00 6d81f41c58c69ddde497e9e640ba5805aa26e78c Converts dummy network device driver to : - percpu stats - 64bit stats - lockless xmit (NETIF_F_LLTX) - performance features added (NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_TSO | NETIF_F_NO_CSUM | NETIF_F_HIGHDMA) Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Converts dummy network device driver to :

- percpu stats

- 64bit stats

- lockless xmit (NETIF_F_LLTX)

- performance features added (NETIF_F_SG | NETIF_F_FRAGLIST |
NETIF_F_TSO | NETIF_F_NO_CSUM | NETIF_F_HIGHDMA)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netdev: convert pseudo drivers to netdev_tx_t 2009-09-01T08:13:40+00:00 Stephen Hemminger shemminger@vyatta.com 2009-08-31T19:50:51+00:00 424efe9caf6047ffbcd6b383ff4d2347254aabf1 These are all drivers that don't touch real hardware. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
These are all drivers that don't touch real hardware.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: use NETDEV_TX_OK instead of 0 in ndo_start_xmit() functions 2009-07-06T02:16:04+00:00 Patrick McHardy kaber@trash.net 2009-06-23T06:03:08+00:00 6ed106549d17474ca17a16057f4c0ed4eba5a7ca This patch is the result of an automatic spatch transformation to convert all ndo_start_xmit() return values of 0 to NETDEV_TX_OK. Some occurences are missed by the automatic conversion, those will be handled in a seperate patch. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.

Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>