Message ID | 1455288410-27046-1-git-send-email-berrange@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
On 12/02/2016 15:46, Daniel P. Berrange wrote: > If io_channel_send_full gets QIO_CHANNEL_ERR_BLOCK it > and has already sent some of the data, it should return > that amount of data, not EAGAIN, as that would cause > the caller to re-try already sent data. > > Unfortunately due to a previous rebase conflict resolution > error, the code for dealing with this was in the wrong > part of the conditional, and so mistakenly ran on other > I/O errors. > > This be seen running > > qemu-system-x86_64 -monitor stdio > > and entering 'info mtree', when running on a slow console > (eg a slow remote ssh session). The monitor would get into > an indefinite loop writing the same data until it managed > to send it all without getting EAGAIN. > > Reported-by: Igor Mammedov <imammedo@redhat.com> > Signed-off-by: Daniel P. Berrange <berrange@redhat.com> > --- > qemu-char.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/qemu-char.c b/qemu-char.c > index 1b7d5da..c2e24a5 100644 > --- a/qemu-char.c > +++ b/qemu-char.c > @@ -896,13 +896,13 @@ static int io_channel_send_full(QIOChannel *ioc, > ioc, &iov, 1, > fds, nfds, NULL); > if (ret == QIO_CHANNEL_ERR_BLOCK) { > - errno = EAGAIN; > - return -1; > - } else if (ret < 0) { > if (offset) { > return offset; > } > > + errno = EAGAIN; > + return -1; > + } else if (ret < 0) { > errno = EINVAL; > return -1; > } > Queued, thanks. Paolo
diff --git a/qemu-char.c b/qemu-char.c index 1b7d5da..c2e24a5 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -896,13 +896,13 @@ static int io_channel_send_full(QIOChannel *ioc, ioc, &iov, 1, fds, nfds, NULL); if (ret == QIO_CHANNEL_ERR_BLOCK) { - errno = EAGAIN; - return -1; - } else if (ret < 0) { if (offset) { return offset; } + errno = EAGAIN; + return -1; + } else if (ret < 0) { errno = EINVAL; return -1; }
If io_channel_send_full gets QIO_CHANNEL_ERR_BLOCK it and has already sent some of the data, it should return that amount of data, not EAGAIN, as that would cause the caller to re-try already sent data. Unfortunately due to a previous rebase conflict resolution error, the code for dealing with this was in the wrong part of the conditional, and so mistakenly ran on other I/O errors. This be seen running qemu-system-x86_64 -monitor stdio and entering 'info mtree', when running on a slow console (eg a slow remote ssh session). The monitor would get into an indefinite loop writing the same data until it managed to send it all without getting EAGAIN. Reported-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Daniel P. Berrange <berrange@redhat.com> --- qemu-char.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)