Re: [Qemu-devel] [Bug 1363641] Re: Build of v2.1.0 fails on armv7l due to undeclared __NR_select

["Michael R. Hines" <mrhines@linux.vnet.ibm.com>]

On 09/09/2014 02:09 AM, Dr. David Alan Gilbert wrote:
> (cc'ing Michael Hines who owns and knows the RDMA code)
>
> * Karl-Philipp Richter (krichter722@aol.de) wrote:
>> ** Description changed:
>>
>>    After `make clean` and `git clean -x -f -d` `git checkout v2.1.0 &&
>>    configure --prefix=/home/user/prefix-qemu-2.1.0 && make` fails due to
>>    missing declarations
>>
>>        CC    qemu-seccomp.o
>>        qemu-seccomp.c:28:1: error: '__NR_select' undeclared here (not in a function)
>>        qemu-seccomp.c:36:1: error: '__NR_mmap' undeclared here (not in a function)
>>        qemu-seccomp.c:57:1: error: '__NR_getrlimit' undeclared here (not in a function)
>>        qemu-seccomp.c:96:1: error: '__NR_time' undeclared here (not in a function)
>>          GEN   qmp-marshal.c
>>        qemu-seccomp.c:186:1: error: '__NR_alarm' undeclared here (not in a function)
>>        make: *** [qemu-seccomp.o] Error 1
>>
>>    Same errors for master 8b3030114a449e66c68450acaac4b66f26d91416.
>>    `configure`should not succeed for a failing build. `config.log` for
>>    v2.1.0 and 8b303011... attached. The content is mostly compiler output
>>    which I think is unusual for `config.log`, but see for yourself.
>>
>>    I'm building on a debian 7.6 chroot on Synology DSM 5.0. `uname -a` says
>>    `Linux diskstatation 3.2.40 #4493 SMP Thu Aug 21 21:43:02 CST 2014
>>    armv7l GNU/Linux`.
>> +
>> + After installing some of the missing header files (-> configure should
>> + fail at the right point with a good error message), i.e. `apt-get
>> + install liblzo2-dev libbsd-dev syslinux-common libhwloc-dev librdmacm-
>> + dev libsnappy-dev libibverbs-dev valgrind linux-headers-3.2.0-4-common`
>> + I'm getting
>> +
>> +      CC    migration-rdma.o
>> +     migration-rdma.c: In function 'ram_chunk_start':
>> +     migration-rdma.c:523:12: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
> is that:
>      return (uint8_t *) (((uintptr_t) rdma_ram_block->local_host_addr)
>                                      + (i << RDMA_REG_CHUNK_SHIFT));
>
> 244:    uint8_t  *local_host_addr; /* local virtual address */
>
> in which case I think the problem is the 'i' which is a uint64_t.
>
>> +     migration-rdma.c: In function '__qemu_rdma_add_block':
>> +     migration-rdma.c:556:49: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:557:49: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c: In function '__qemu_rdma_delete_block':
>> +     migration-rdma.c:664:45: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:699:49: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c: In function 'qemu_rdma_search_ram_block':
>> +     migration-rdma.c:1113:49: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c: In function 'qemu_rdma_register_and_get_keys':
>> +     migration-rdma.c:1176:50: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c:1177:29: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c:1177:51: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c:1178:29: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c: In function 'qemu_rdma_post_send_control':
>> +     migration-rdma.c:1562:36: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c: In function 'qemu_rdma_post_recv_control':
>> +     migration-rdma.c:1616:37: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c: In function 'qemu_rdma_write_one':
>> +     migration-rdma.c:1864:16: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c:1868:53: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:1922:52: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:1923:50: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:1977:49: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:1998:49: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c:2010:58: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
>> +     migration-rdma.c: In function 'qemu_rdma_registration_handle':
>> +     migration-rdma.c:3027:21: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     migration-rdma.c:3092:41: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
>> +     cc1: all warnings being treated as errors
>> +     make: *** [migration-rdma.o] Error 1
> There's lots of stuff there; I think it's one for Michael because it involves understanding the structures
> and which ones get passed over the wire etc.
> (The quick fix would probably to guard the RDMA configure with a test for 32bit pointers)
>
> Dave
>
>


I could use some advice from the community on this: In particular, I 
have *zero* 32-bit machine to
fix this on........ now, I could easily create a 32-bit machine, but I 
simply don't have any RDMA hardware
for which to run the 32-bit virtual machine against.

So, what are my options? Can I just submit a patch that completely 
disables RDMA in 32-bit environments?

Is that a bad thing?

- Michael