Fix userspace_device list corruption. The corruption was caused by clients not being removed when adapters with such clients were themselves removed. Something like the following would trigger it (assuming i2c-stub gets adapter number 3):
# modprobe i2c-stub chip_addr=0x50 # echo 24c08 0x50 > /sys/bus/i2c/devices/i2c-3/new_device # rmmod i2c-stub # modprobe i2c-stub chip_addr=0x50 # echo 24c08 0x50 > /sys/bus/i2c/devices/i2c-3/new_device For the records, the stack trace in the kernel logs look like this: kernel: WARNING: at lib/list_debug.c:30 __list_add+0x8b/0x90() kernel: Hardware name: (...) kernel: list_add corruption. prev->next should be next (c137fc84), but was (null). (prev=f57111b8). kernel: Modules linked in: (...) kernel: Pid: 4669, comm: bash Not tainted 2.6.32-rc8 #259 kernel: Call Trace: kernel: [<c111eb8b>] ? __list_add+0x8b/0x90 kernel: [<c111eb8b>] ? __list_add+0x8b/0x90 kernel: [<c103265c>] warn_slowpath_common+0x6c/0xc0 kernel: [<c111eb8b>] ? __list_add+0x8b/0x90 kernel: [<c10326f6>] warn_slowpath_fmt+0x26/0x30 kernel: [<c111eb8b>] __list_add+0x8b/0x90 kernel: [<c11ba165>] i2c_sysfs_new_device+0x1c5/0x250 kernel: [<c10861be>] ? might_fault+0x2e/0x80 kernel: [<c11b9fa0>] ? i2c_sysfs_new_device+0x0/0x250 kernel: [<c118c625>] dev_attr_store+0x25/0x30 kernel: [<c10e305c>] sysfs_write_file+0x9c/0xf0 kernel: [<c109d35c>] vfs_write+0x9c/0x160 kernel: [<c10e2fc0>] ? sysfs_write_file+0x0/0xf0 kernel: [<c109d4dd>] sys_write+0x3d/0x70 kernel: [<c1002ed8>] sysenter_do_call+0x12/0x36 Signed-off-by: Jean Delvare <[email protected]> --- drivers/i2c/i2c-core.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- linux-2.6.32-rc8.orig/drivers/i2c/i2c-core.c 2009-11-19 13:05:47.000000000 +0100 +++ linux-2.6.32-rc8/drivers/i2c/i2c-core.c 2009-11-22 14:45:53.000000000 +0100 @@ -762,6 +762,7 @@ int i2c_del_adapter(struct i2c_adapter * { int res = 0; struct i2c_adapter *found; + struct i2c_client *client, *next; /* First make sure that this adapter was ever added */ mutex_lock(&core_lock); @@ -781,6 +782,16 @@ int i2c_del_adapter(struct i2c_adapter * if (res) return res; + /* Remove devices instantiated from sysfs */ + list_for_each_entry_safe(client, next, &userspace_devices, detected) { + if (client->adapter == adap) { + dev_dbg(&adap->dev, "Removing %s at 0x%x\n", + client->name, client->addr); + list_del(&client->detected); + i2c_unregister_device(client); + } + } + /* Detach any active clients. This can't fail, thus we do not checking the returned value. */ res = device_for_each_child(&adap->dev, NULL, __unregister_client); -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
