Re: [Qemu-devel] qemu-kvm build issue on RHEL5.1

2010-11-05 Thread Hidetoshi Seto 
(2010/11/05 2:03), Chris Wright wrote:
 * Hidetoshi Seto (seto.hideto...@jp.fujitsu.com) wrote:
 (2010/10/14 4:11), Blue Swirl wrote:
 On Wed, Oct 13, 2010 at 8:00 AM, Hidetoshi Seto
 seto.hideto...@jp.fujitsu.com wrote:
 (Add CC to k...@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
   CClibhw64/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

Re: [Qemu-devel] qemu-kvm build issue on RHEL5.1

2010-10-13 Thread Hidetoshi Seto 
(Add CC to k...@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
   CClibhw64/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.

Thanks,
H.Seto

=

[PATCH] virtio-9p: fix build on !CONFIG_UTIMENSAT

This removes following warnings on RHEL5, which has utimensat syscall
but has old glibc that doesn't have support for it:

hw/virtio-9p-local.c: In function 'local_utimensat':
hw/virtio-9p-local.c:479: warning: implicit declaration of function 'utimensat'
hw/virtio-9p-local.c:479: warning: nested extern declaration of 'utimensat'

and

hw/virtio-9p.c: In function 'v9fs_setattr_post_chmod':
hw/virtio-9p.c:1410: error: 'UTIME_NOW' undeclared (first use in this function)
hw/virtio-9p.c:1410: error: (Each undeclared identifier is reported only once
hw/virtio-9p.c:1410: error: for each function it appears in.)
hw/virtio-9p.c:1413: error: 'UTIME_OMIT' undeclared (first use in this function)
hw/virtio-9p.c: In function 'v9fs_wstat_post_chmod':
hw/virtio-9p.c:2905: error: 'UTIME_OMIT' undeclared (first use in this function)

Signed-off-by: Hidetoshi Seto seto.hideto...@jp.fujitsu.com
---
 hw/virtio-9p-local.c |8 
 hw/virtio-9p.c   |9 +
 2 files changed, 17 insertions(+), 0 deletions(-)

diff --git a/hw/virtio-9p-local.c b/hw/virtio-9p-local.c
index 57f9243..e075c27 100644
--- a/hw/virtio-9p-local.c
+++ b/hw/virtio-9p-local.c
@@ -18,6 +18,9 @@
 #include sys/socket.h
 #include sys/un.h
 #include attr/xattr.h
+#ifndef CONFIG_UTIMENSAT
+#include syscall.h
+#endif
 
 static const char *rpath(FsContext *ctx, const char *path)
 {
@@ -476,7 +479,12 @@ static int local_chown(FsContext *fs_ctx, const char 
*path, FsCred *credp)
 static int local_utimensat(FsContext *s, const char *path,
   const struct timespec *buf)
 {
+#ifndef CONFIG_UTIMENSAT
+return syscall(SYS_utimensat, AT_FDCWD, rpath(s, path), buf,
+   AT_SYMLINK_NOFOLLOW);
+#else
 return utimensat(AT_FDCWD, rpath(s, path), buf, AT_SYMLINK_NOFOLLOW);
+#endif
 }
 
 static int local_remove(FsContext *ctx, const char *path)
diff --git a/hw/virtio-9p.c b/hw/virtio-9p.c
index 32fa3bc..efe5c51 100644
--- a/hw/virtio-9p.c
+++ b/hw/virtio-9p.c
@@ -1393,6 +1393,15 @@ out:
 qemu_free(vs);
 }
 
+#ifndef CONFIG_UTIMENSAT
+#ifndef UTIME_NOW
+# define UTIME_NOW ((1l  30) - 1l)
+#endif
+#ifndef UTIME_OMIT
+# define UTIME_OMIT((1l  30) - 2l)
+#endif
+#endif
+
 static void v9fs_setattr_post_chmod(V9fsState *s, V9fsSetattrState *vs, int 
err)
 {
 if (err == -1) {
-- 
1.7.3.1

RE: [Qemu-devel] qemu-kvm build issue on RHEL5.1

2010-10-13 Thread Hao, Xudong 
Hidetoshi Seto wrote:
 (Add CC to k...@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
   CClibhw64/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.
 
 Thanks,
 H.Seto
 
 =
 
 [PATCH] virtio-9p: fix build on !CONFIG_UTIMENSAT
 
 This removes following warnings on RHEL5, which has utimensat syscall
 but has old glibc that doesn't have support for it:
 
 hw/virtio-9p-local.c: In function 'local_utimensat':
 hw/virtio-9p-local.c:479: warning: implicit declaration of function
 'utimensat' hw/virtio-9p-local.c:479: warning: nested extern
 declaration of 'utimensat' 
 
 and
 
 hw/virtio-9p.c: In function 'v9fs_setattr_post_chmod':
 hw/virtio-9p.c:1410: error: 'UTIME_NOW' undeclared (first use in this
 function) hw/virtio-9p.c:1410: error: (Each undeclared identifier is
 reported only once hw/virtio-9p.c:1410: error: for each function it
 appears in.) 
 hw/virtio-9p.c:1413: error: 'UTIME_OMIT' undeclared (first use in
 this function) hw/virtio-9p.c: In function 'v9fs_wstat_post_chmod':
 hw/virtio-9p.c:2905: error: 'UTIME_OMIT' undeclared (first use in
 this function) 
 
 Signed-off-by: Hidetoshi Seto seto.hideto...@jp.fujitsu.com
 ---
  hw/virtio-9p-local.c |8 
  hw/virtio-9p.c   |9 +
  2 files changed, 17 insertions(+), 0 deletions(-)
 
 diff --git a/hw/virtio-9p-local.c b/hw/virtio-9p-local.c
 index 57f9243..e075c27 100644
 --- a/hw/virtio-9p-local.c
 +++ b/hw/virtio-9p-local.c
 @@ -18,6 +18,9 @@
  #include sys/socket.h
  #include sys/un.h
  #include attr/xattr.h
 +#ifndef CONFIG_UTIMENSAT
 +#include syscall.h
 +#endif
 
  static const char *rpath(FsContext *ctx, const char *path)
  {
 @@ -476,7 +479,12 @@ static int local_chown(FsContext *fs_ctx, const
  char *path, FsCred *credp) static int local_utimensat(FsContext *s,
  const char *path, const struct timespec *buf)
  {
 +#ifndef CONFIG_UTIMENSAT
 +return syscall(SYS_utimensat, AT_FDCWD, rpath(s, path), buf,
 +   AT_SYMLINK_NOFOLLOW);
 +#else
  return utimensat(AT_FDCWD, rpath(s, path), buf,
 AT_SYMLINK_NOFOLLOW); +#endif
  }
 
  static int local_remove(FsContext *ctx, const char *path)
 diff --git a/hw/virtio-9p.c b/hw/virtio-9p.c
 index 32fa3bc..efe5c51 100644
 --- a/hw/virtio-9p.c
 +++ b/hw/virtio-9p.c
 @@ -1393,6 +1393,15 @@ out:
  qemu_free(vs);
  }
 
 +#ifndef CONFIG_UTIMENSAT
 +#ifndef UTIME_NOW
 +# define UTIME_NOW   ((1l  30) - 1l)
 +#endif
 +#ifndef UTIME_OMIT
 +# define UTIME_OMIT  ((1l  30) - 2l)
 +#endif
 +#endif
 +
  static void v9fs_setattr_post_chmod(V9fsState *s, V9fsSetattrState
  *vs, int err) {
  if (err == -1) {

Seto, your patch works fine for me, verified on my RHEL5 system.

Thanks,
Xudong

Re: [Qemu-devel] qemu-kvm build issue on RHEL5.1

2010-10-13 Thread Blue Swirl 
On Wed, Oct 13, 2010 at 8:00 AM, Hidetoshi Seto
seto.hideto...@jp.fujitsu.com wrote:
 (Add CC to k...@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.

What happens if the system headers do not define SYS_utimensat?

Re: [Qemu-devel] qemu-kvm build issue on RHEL5.1

2010-10-13 Thread Hidetoshi Seto 
(2010/10/14 4:11), Blue Swirl wrote:
 On Wed, Oct 13, 2010 at 8:00 AM, Hidetoshi Seto
 seto.hideto...@jp.fujitsu.com wrote:
 (Add CC to k...@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
   CClibhw64/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. 

... Or is it better to put abort() here instead of syscall?

 
 What happens if the system headers do not define SYS_utimensat?

I suppose build will fail, say, we might need incremental patch
named fix build on RHEL4 or so.
But I have no idea, whether there could be a workaround if there
is no utimensat, whether we could provide something like wrapper
named compat_utimensat or qemu_utimensat, and/or whether it makes
sense if virtio-9p have dependency with presence of utimensat.


Thanks,
H.Seto

[Qemu-devel] qemu-kvm build issue on RHEL5.1

2010-10-11 Thread Hao, Xudong 
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
  CClibhw64/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