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Date: Sat, 31 Mar 2007 21:18:00 -0400 (EDT)
From: Stuart Anderson <anderson@netsweng.com>
Subject: Re: [Qemu-devel] [PATCH] semaphore syscalls - refresh
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To: Thiemo Seufer <ths@networkno.de>
Cc: qemu-devel@nongnu.org

On Sat, 31 Mar 2007, Thiemo Seufer wrote:

>> +    switch( cmd ) {
>> +	case GETALL:
>> +	case SETALL:
>> +	case IPC_STAT:
>> +	case IPC_SET:
>> +           lock_user_struct(target_su, target_addr, 1);
>> +	   target_to_host_semid_ds(ds,target_su->buf);
>> +	   host_su->buf = ds;
>> +           unlock_user_struct(target_su, target_addr, 0);
>> +	   break;
>
> I don't see how this can work with target_su being an uninitialized pointer.

#define lock_user_struct(host_ptr, guest_addr, copy) \
     host_ptr = lock_user(guest_addr, sizeof(*host_ptr), copy)

target_su is the left hand side of the assignment. The macro just hides it.


                                 Stuart

Stuart R. Anderson                               anderson@netsweng.com
Network & Software Engineering                   http://www.netsweng.com/
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