diff options
author | Michael Tokarev <mjt@tls.msk.ru> | 2010-06-02 14:33:01 -0300 |
---|---|---|
committer | Anthony Liguori <aliguori@us.ibm.com> | 2010-06-22 15:15:30 -0500 |
commit | 91ca60e01277da2184d9c3f992c440cb5aa264c4 (patch) | |
tree | e86d8211635f69f90b6bbbeec9856cbbb6807cc1 /net/tap-linux.c | |
parent | 49b586a922c1818cbd9f576600f72bff182bc257 (diff) | |
download | qemu-91ca60e01277da2184d9c3f992c440cb5aa264c4.zip qemu-91ca60e01277da2184d9c3f992c440cb5aa264c4.tar.gz qemu-91ca60e01277da2184d9c3f992c440cb5aa264c4.tar.bz2 |
give some useful error messages when tap open
In net/tap-linux.c, when manipulation of /dev/net/tun fails, it prints
(with fprintf) something like this:
warning: could not open /dev/net/tun: no virtual network emulation
this has 2 issues:
1) it is not a warning really, it's a fatal error (kvm exits after
that),
2) there's no indication as of what's actually wrong: printing errno there
is helpful.
The patch below removes the "warning" prefix, uses %m (since it's linux,
%m is available as format modifier), and changes fprintf() to %qemu_error().
Now it prints something like this instead:
could not configure /dev/net/tun: Device or resource busy
(there are 2 messages like that in the same function)
This fixes Debian bug #578154, see
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578154
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'net/tap-linux.c')
-rw-r--r-- | net/tap-linux.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/net/tap-linux.c b/net/tap-linux.c index 03b8301..c92983c 100644 --- a/net/tap-linux.c +++ b/net/tap-linux.c @@ -33,14 +33,16 @@ #include "qemu-common.h" #include "qemu-error.h" +#define PATH_NET_TUN "/dev/net/tun" + int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required) { struct ifreq ifr; int fd, ret; - TFR(fd = open("/dev/net/tun", O_RDWR)); + TFR(fd = open(PATH_NET_TUN, O_RDWR)); if (fd < 0) { - fprintf(stderr, "warning: could not open /dev/net/tun: no virtual network emulation\n"); + error_report("could not open %s: %m", PATH_NET_TUN); return -1; } memset(&ifr, 0, sizeof(ifr)); @@ -71,7 +73,7 @@ int tap_open(char *ifname, int ifname_size, int *vnet_hdr, int vnet_hdr_required pstrcpy(ifr.ifr_name, IFNAMSIZ, "tap%d"); ret = ioctl(fd, TUNSETIFF, (void *) &ifr); if (ret != 0) { - fprintf(stderr, "warning: could not configure /dev/net/tun: no virtual network emulation\n"); + error_report("could not configure %s (%s): %m", PATH_NET_TUN, ifr.ifr_name); close(fd); return -1; } |