(2010/11/05 2:03), Chris Wright wrote: > * Hidetoshi Seto (seto.hidetoshi@xxxxxxxxxxxxxx) wrote: >> (2010/10/14 4:11), Blue Swirl wrote: >>> On Wed, Oct 13, 2010 at 8:00 AM, Hidetoshi Seto >>> <seto.hidetoshi@xxxxxxxxxxxxxx> wrote: >>>> (Add CC to kvm@vger) >>>> >>>> (2010/10/12 10:52), Hao, Xudong wrote: >>>>> Hi, >>>>> Currently qemu-kvm build fail on RHEL5 with gcc 4.1.2, build can pass on Fedora11 with gcc 4.4.1, can anybody look on RHEL5 system? >>>>> >>>>> Gcc: 4.1.2 >>>>> system: RHEL5.1 >>>>> qemu-kvm: 85566812a4f8cae721fea0224e05a7e75c08c5dd >>>>> >>>>> ... >>>>> LINK qemu-img >>>>> LINK qemu-io >>>>> CC libhw64/virtio-9p-local.o >>>>> cc1: warnings being treated as errors >>>>> /home/source/qemu-kvm/hw/virtio-9p-local.c: In function 'local_utimensat': >>>>> /home/source/qemu-kvm/hw/virtio-9p-local.c:479: warning: implicit declaration of function 'utimensat' >>>>> /home/source/qemu-kvm/hw/virtio-9p-local.c:479: warning: nested extern declaration of 'utimensat' >>>>> make[1]: *** [virtio-9p-local.o] Error 1 >>>>> make: *** [subdir-libhw64] Error 2 >>>>> >>>>> >>>>> Best Regards, >>>>> Xudong Hao >>>> >>>> It seems that this issue is caused by the old glibc. >>>> Though I don't know well about virtio-9p and suppose there >>>> should be better fix, I confirmed that following change >>>> removed the warnings. >>> >>> But then the system call will be made blindly without checking if the >>> kernel supports utimensat(). At the minimum, there should be a sane >>> response to ENOSYS error. >> >> Yes. But I'm not sure how this virtio-9p should behave if there is >> no utimensat. I think it will be better to fix this warning first >> to allow fellows using RHEL5 to restart contribute on qemu-kvm, >> and change this issue to virtio-9p specific problem to allow >> specialists of virtio-9p to have discussion for fix without >> bothering other developers. > > One way to workaround this is to simply not install libattr-devel > (effecitvely disabling virtio-9p). > > But I agree with Blue Swirl, need a better fallback plan. A qemu local > implementation of something like qemu_utimensat() that simply uses > glibc/kernel interface when available and falls back to using utimes() > makes sense to me. Then the worst case is loss of resolution from ns to > us. According to the commit 74bc02b2d2272dc88fb98d43e631eb154717f517, the title "Do not reset atime" can tell us that the original motivation to use utimensat() is not for the resolution. Anyway, I agree to have something like qemu_utimensat(). I made a patch for the first step, and will post it next to this reply. Thanks, H.Seto -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
