Re: [Bugme-new] [Bug 8957] New: Exported functions and variables should not be reachable by the outside of the module until module_init finishes

[Robert Hancock <hancockr@shaw.ca>]

Andrew Morton wrote:
> On Wed, 29 Aug 2007 11:33:06 -0700 (PDT) bugme-daemon@bugzilla.kernel.org wrote:
> 
>> http://bugzilla.kernel.org/show_bug.cgi?id=8957
>>
>>            Summary: Exported functions and variables should not be reachable
>>                     by the outside of the module until module_init finishes
>>            Product: Other
>>            Version: 2.5
>>      KernelVersion: 2.6.23-rc4
>>           Platform: All
>>         OS/Version: Linux
>>               Tree: Mainline
>>             Status: NEW
>>           Severity: normal
>>           Priority: P1
>>          Component: Modules
>>         AssignedTo: other_modules@kernel-bugs.osdl.org
>>         ReportedBy: mattilinnanvuori@yahoo.com
>>
>>
>> Problem Description: a module's exported functions can be called before before
>> they are properly initialized by the module_init function.
>>
>> Steps to reproduce: write a module that exports functions that require
>> initialization by the module_init function to work correctly.
>>
>> E.g. spin lock variables are no longer allowed to be initialized by C
>> initializers of the module but only by spin_lock_init that can be called by the
>> module_init function. If an exported function calls spin_lock before it is
>> initialized, it deadlocks.
>>
> 
> ooh, nice bug ;)

Under what circumstances is this actually happening? What are these 
functions that are being called?

Normally things are set up such that this isn't a problem, i.e. if 
module A depends on module B, module A can't load until module B is 
finished loading.

-- 
Robert Hancock      Saskatoon, SK, Canada
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