Re: raw disks no longer work in latest kvm (kvm-88 was fine)

[Avi Kivity <avi@redhat.com>]

On 03/07/2010 09:07 PM, Antoine Martin wrote:
>>>> Antoine, can you check this?  ltrace may help,
>>> This the only part that looked slightly relevant:
>>> [pid 26883] __xstat64(1, "./vm/media_fs", 0x7fff92e40500) = 0
>>> [pid 26883] malloc(48)                           = 0x2a38d60
>>> [pid 26883] memset(0x2a38d60, '\000', 48)        = 0x2a38d60
>>> [pid 26883] open64("./vm/media_fs", 540674, 00)  = 12
>>> [pid 26883] posix_memalign(0x7fff92e40560, 512, 16384, -1, 48) = 0
>>> [pid 26883] lseek64(12, 0, 2, 0x7f404f2f3e60, 4) = 0x133c4820600
>>
>>
>> Where's pread/preadv?  Did you use -f?
>
> Yes I did.
> ltrace -f bash ./vm/start.sh >& trace.log

Well, some variant of pread should have shown up.  Maybe it's the ltrace 
-f race.

>>>> or run 'strings libc.so | grep pread'.
>>>>
>>> strings /lib/libc.so.6 | grep pread
>>> preadv
>>> preadv64
>>> pread
>>> __pread64_chk
>>> __pread64
>>> __pread_chk
>>>
>>
>> So it does seem glibc emulates preadv.
>>
>> Perhaps https://bugzilla.redhat.com/show_bug.cgi?id=563103 ?
> This a gentoo box... but yes, this does look similar doesn't it?

What version of glibc do you have installed?

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.