Use common qemu_set_blocking() instead.
Note that pre-patch the behavior of Win32 and Linux realizations
are inconsistent: we ignore failure for Win32, and assert success
for Linux.
How do we convert the callers?
1. Most of callers call qemu_socket_set_nonblock() on a
freshly created socket fd, in conditions when we may simply
report an error. Seems correct switching to error handling
both for Windows (pre-patch error is ignored) and Linux
(pre-patch we assert success). Anyway, we normally don't
expect errors in these cases.
Still in tests let's use &error_abort for simplicity.
What are exclusions?
2. hw/virtio/vhost-user.c - we are inside #ifdef CONFIG_LINUX,
so no damage in switching to error handling from assertion.
3. io/channel-socket.c: here we convert both old calls to
qemu_socket_set_nonblock() and qemu_socket_set_block() to
one new call. Pre-patch we assert success for Linux in
qemu_socket_set_nonblock(), and ignore all other errors here.
Still, all callers pass errp=NULL to qio_channel_set_blocking(),
so after patch we ignore all errors. Switching from assertion
to ignoring may be not very good, but still acceptable, keeping
in mind that all callers of qio_channel_set_blocking() do
explicitly ignore the error.
4. util/vhost-user-server - compiled only for Linux (see
util/meson.build), so we are safe, switching from assertion to
&error_abort.
Note: In qga/channel-posix.c we use g_warning(), where g_printerr()
would actually be a better choice. Still let's for now follow
common style of qga, where g_warning() is commonly used to print
such messages, and no call to g_printerr(). Converting everything
to use g_printerr() should better be another series.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Peter Xu <peterx@redhat.com>
---
contrib/ivshmem-server/ivshmem-server.c | 6 +++++-
hw/hyperv/syndbg.c | 4 +++-
hw/virtio/vhost-user.c | 5 ++++-
include/qemu/sockets.h | 1 -
io/channel-socket.c | 7 +++----
net/dgram.c | 16 +++++++++++++---
net/l2tpv3.c | 5 +++--
net/socket.c | 20 ++++++++++++++++----
qga/channel-posix.c | 7 ++++++-
tests/unit/socket-helpers.c | 5 ++++-
tests/unit/test-crypto-tlssession.c | 8 ++++----
util/oslib-posix.c | 7 -------
util/oslib-win32.c | 5 -----
util/vhost-user-server.c | 4 ++--
14 files changed, 63 insertions(+), 37 deletions(-)
diff --git a/contrib/ivshmem-server/ivshmem-server.c b/contrib/ivshmem-server/ivshmem-server.c
index 2f3c7320a6..a65943d0b8 100644
--- a/contrib/ivshmem-server/ivshmem-server.c
+++ b/contrib/ivshmem-server/ivshmem-server.c
@@ -146,9 +146,13 @@ ivshmem_server_handle_new_conn(IvshmemServer *server)
return -1;
}
- qemu_socket_set_nonblock(newfd);
IVSHMEM_SERVER_DEBUG(server, "accept()=%d\n", newfd);
+ if (!qemu_set_blocking(newfd, false, NULL)) {
+ close(newfd);
+ return -1;
+ }
+
/* allocate new structure for this peer */
peer = g_malloc0(sizeof(*peer));
peer->sock_fd = newfd;
diff --git a/hw/hyperv/syndbg.c b/hw/hyperv/syndbg.c
index ac7e15f6f1..bcdfdf6af7 100644
--- a/hw/hyperv/syndbg.c
+++ b/hw/hyperv/syndbg.c
@@ -338,7 +338,9 @@ static void hv_syndbg_realize(DeviceState *dev, Error **errp)
return;
}
- qemu_socket_set_nonblock(syndbg->socket);
+ if (!qemu_set_blocking(syndbg->socket, false, errp)) {
+ return;
+ }
syndbg->servaddr.sin_port = htons(syndbg->host_port);
syndbg->servaddr.sin_family = AF_INET;
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 1e1d6b0d6e..36c9c2e04d 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -2039,7 +2039,10 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp)
error_setg(errp, "%s: Failed to get ufd", __func__);
return -EIO;
}
- qemu_socket_set_nonblock(ufd);
+ if (!qemu_set_blocking(ufd, false, errp)) {
+ close(ufd);
+ return -EINVAL;
+ }
/* register ufd with userfault thread */
u->postcopy_fd.fd = ufd;
diff --git a/include/qemu/sockets.h b/include/qemu/sockets.h
index c562690d89..6477f90b9e 100644
--- a/include/qemu/sockets.h
+++ b/include/qemu/sockets.h
@@ -48,7 +48,6 @@ int socket_set_cork(int fd, int v);
int socket_set_nodelay(int fd);
void qemu_socket_set_block(int fd);
int qemu_socket_try_set_nonblock(int fd);
-void qemu_socket_set_nonblock(int fd);
int socket_set_fast_reuse(int fd);
#ifdef WIN32
diff --git a/io/channel-socket.c b/io/channel-socket.c
index 21f8f2e0c5..f7e3cb9742 100644
--- a/io/channel-socket.c
+++ b/io/channel-socket.c
@@ -825,11 +825,10 @@ qio_channel_socket_set_blocking(QIOChannel *ioc,
{
QIOChannelSocket *sioc = QIO_CHANNEL_SOCKET(ioc);
- if (enabled) {
- qemu_socket_set_block(sioc->fd);
- } else {
- qemu_socket_set_nonblock(sioc->fd);
+ if (!qemu_set_blocking(sioc->fd, enabled, errp)) {
+ return -1;
}
+
return 0;
}
diff --git a/net/dgram.c b/net/dgram.c
index 48f653bceb..fb9ded30df 100644
--- a/net/dgram.c
+++ b/net/dgram.c
@@ -226,7 +226,10 @@ static int net_dgram_mcast_create(struct sockaddr_in *mcastaddr,
}
}
- qemu_socket_set_nonblock(fd);
+ if (!qemu_set_blocking(fd, false, errp)) {
+ goto fail;
+ }
+
return fd;
fail:
if (fd >= 0) {
@@ -504,7 +507,11 @@ int net_init_dgram(const Netdev *netdev, const char *name,
close(fd);
return -1;
}
- qemu_socket_set_nonblock(fd);
+
+ if (!qemu_set_blocking(fd, false, errp)) {
+ close(fd);
+ return -1;
+ }
dest_len = sizeof(raddr_in);
dest_addr = g_malloc(dest_len);
@@ -551,7 +558,10 @@ int net_init_dgram(const Netdev *netdev, const char *name,
close(fd);
return -1;
}
- qemu_socket_set_nonblock(fd);
+ if (!qemu_set_blocking(fd, false, errp)) {
+ close(fd);
+ return -1;
+ }
dest_len = sizeof(raddr_un);
dest_addr = g_malloc(dest_len);
diff --git a/net/l2tpv3.c b/net/l2tpv3.c
index b5547cb917..cdfc641aa6 100644
--- a/net/l2tpv3.c
+++ b/net/l2tpv3.c
@@ -648,6 +648,9 @@ int net_init_l2tpv3(const Netdev *netdev,
error_setg(errp, "could not bind socket err=%i", errno);
goto outerr;
}
+ if (!qemu_set_blocking(fd, false, errp)) {
+ goto outerr;
+ }
freeaddrinfo(result);
@@ -709,8 +712,6 @@ int net_init_l2tpv3(const Netdev *netdev,
s->vec = g_new(struct iovec, MAX_L2TPV3_IOVCNT);
s->header_buf = g_malloc(s->header_size);
- qemu_socket_set_nonblock(fd);
-
s->fd = fd;
s->counter = 0;
diff --git a/net/socket.c b/net/socket.c
index 784dda686f..db25e3d9ae 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -295,7 +295,10 @@ static int net_socket_mcast_create(struct sockaddr_in *mcastaddr,
}
}
- qemu_socket_set_nonblock(fd);
+ if (!qemu_set_blocking(fd, false, errp)) {
+ goto fail;
+ }
+
return fd;
fail:
if (fd >= 0)
@@ -508,7 +511,10 @@ static int net_socket_listen_init(NetClientState *peer,
error_setg_errno(errp, errno, "can't create stream socket");
return -1;
}
- qemu_socket_set_nonblock(fd);
+ if (!qemu_set_blocking(fd, false, errp)) {
+ close(fd);
+ return -1;
+ }
socket_set_fast_reuse(fd);
@@ -556,7 +562,10 @@ static int net_socket_connect_init(NetClientState *peer,
error_setg_errno(errp, errno, "can't create stream socket");
return -1;
}
- qemu_socket_set_nonblock(fd);
+ if (!qemu_set_blocking(fd, false, errp)) {
+ close(fd);
+ return -1;
+ }
connected = 0;
for(;;) {
@@ -671,7 +680,10 @@ static int net_socket_udp_init(NetClientState *peer,
close(fd);
return -1;
}
- qemu_socket_set_nonblock(fd);
+ if (!qemu_set_blocking(fd, false, errp)) {
+ close(fd);
+ return -1;
+ }
s = net_socket_fd_init_dgram(peer, model, name, fd, 0, NULL, errp);
if (!s) {
diff --git a/qga/channel-posix.c b/qga/channel-posix.c
index 465d688ecb..9ccc8b7bd1 100644
--- a/qga/channel-posix.c
+++ b/qga/channel-posix.c
@@ -28,6 +28,7 @@ static gboolean ga_channel_listen_accept(GIOChannel *channel,
GAChannel *c = data;
int ret, client_fd;
bool accepted = false;
+ Error *err = NULL;
g_assert(channel != NULL);
@@ -36,7 +37,11 @@ static gboolean ga_channel_listen_accept(GIOChannel *channel,
g_warning("error converting fd to gsocket: %s", strerror(errno));
goto out;
}
- qemu_socket_set_nonblock(client_fd);
+ if (!qemu_set_blocking(client_fd, false, &err)) {
+ g_warning("%s", error_get_pretty(err));
+ error_free(err);
+ goto out;
+ }
ret = ga_channel_client_add(c, client_fd);
if (ret) {
g_warning("error setting up connection");
diff --git a/tests/unit/socket-helpers.c b/tests/unit/socket-helpers.c
index 37db24f72a..1b7e283f24 100644
--- a/tests/unit/socket-helpers.c
+++ b/tests/unit/socket-helpers.c
@@ -88,7 +88,10 @@ static int socket_can_bind_connect(const char *hostname, int family)
goto cleanup;
}
- qemu_socket_set_nonblock(cfd);
+ if (!qemu_set_blocking(cfd, false, NULL)) {
+ goto cleanup;
+ }
+
if (connect(cfd, (struct sockaddr *)&ss, sslen) < 0) {
if (errno == EINPROGRESS) {
check_soerr = true;
diff --git a/tests/unit/test-crypto-tlssession.c b/tests/unit/test-crypto-tlssession.c
index 554054e934..61311cbe6e 100644
--- a/tests/unit/test-crypto-tlssession.c
+++ b/tests/unit/test-crypto-tlssession.c
@@ -112,8 +112,8 @@ static void test_crypto_tls_session_psk(void)
* thread, so we need these non-blocking to avoid deadlock
* of ourselves
*/
- qemu_socket_set_nonblock(channel[0]);
- qemu_socket_set_nonblock(channel[1]);
+ qemu_set_blocking(channel[0], false, &error_abort);
+ qemu_set_blocking(channel[1], false, &error_abort);
clientCreds = test_tls_creds_psk_create(
QCRYPTO_TLS_CREDS_ENDPOINT_CLIENT,
@@ -264,8 +264,8 @@ static void test_crypto_tls_session_x509(const void *opaque)
* thread, so we need these non-blocking to avoid deadlock
* of ourselves
*/
- qemu_socket_set_nonblock(channel[0]);
- qemu_socket_set_nonblock(channel[1]);
+ qemu_set_blocking(channel[0], false, &error_abort);
+ qemu_set_blocking(channel[1], false, &error_abort);
#define CLIENT_CERT_DIR "tests/test-crypto-tlssession-client/"
#define SERVER_CERT_DIR "tests/test-crypto-tlssession-server/"
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index c737701075..599993d40d 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -275,13 +275,6 @@ int qemu_socket_try_set_nonblock(int fd)
return g_unix_set_fd_nonblocking(fd, true, NULL) ? 0 : -errno;
}
-void qemu_socket_set_nonblock(int fd)
-{
- int f;
- f = qemu_socket_try_set_nonblock(fd);
- assert(f == 0);
-}
-
int socket_set_fast_reuse(int fd)
{
int val = 1, ret;
diff --git a/util/oslib-win32.c b/util/oslib-win32.c
index 03044f5b59..1566eb57e7 100644
--- a/util/oslib-win32.c
+++ b/util/oslib-win32.c
@@ -211,11 +211,6 @@ int qemu_socket_try_set_nonblock(int fd)
return 0;
}
-void qemu_socket_set_nonblock(int fd)
-{
- (void)qemu_socket_try_set_nonblock(fd);
-}
-
int socket_set_fast_reuse(int fd)
{
/* Enabling the reuse of an endpoint that was used by a socket still in
diff --git a/util/vhost-user-server.c b/util/vhost-user-server.c
index b19229074a..8dcd32dc65 100644
--- a/util/vhost-user-server.c
+++ b/util/vhost-user-server.c
@@ -78,7 +78,7 @@ static void vmsg_unblock_fds(VhostUserMsg *vmsg)
}
for (i = 0; i < vmsg->fd_num; i++) {
- qemu_socket_set_nonblock(vmsg->fds[i]);
+ qemu_set_blocking(vmsg->fds[i], false, &error_abort);
}
}
@@ -303,7 +303,7 @@ set_watch(VuDev *vu_dev, int fd, int vu_evt,
vu_fd_watch->fd = fd;
vu_fd_watch->cb = cb;
- qemu_socket_set_nonblock(fd);
+ qemu_set_blocking(fd, false, &error_abort);
aio_set_fd_handler(server->ctx, fd, kick_handler,
NULL, NULL, NULL, vu_fd_watch);
vu_fd_watch->vu_dev = vu_dev;
--
2.48.1On Thu, Sep 11, 2025 at 12:20:02PM +0300, Vladimir Sementsov-Ogievskiy wrote:
> Use common qemu_set_blocking() instead.
>
> Note that pre-patch the behavior of Win32 and Linux realizations
> are inconsistent: we ignore failure for Win32, and assert success
> for Linux.
>
> How do we convert the callers?
> 3. io/channel-socket.c: here we convert both old calls to
> qemu_socket_set_nonblock() and qemu_socket_set_block() to
> one new call. Pre-patch we assert success for Linux in
> qemu_socket_set_nonblock(), and ignore all other errors here.
> Still, all callers pass errp=NULL to qio_channel_set_blocking(),
> so after patch we ignore all errors. Switching from assertion
> to ignoring may be not very good, but still acceptable, keeping
> in mind that all callers of qio_channel_set_blocking() do
> explicitly ignore the error.
This is a bit questionable. IMHO the reason why nearly all
callers pass errp=NULL is laziness based on the assumption
that the code actually asserts, and no one thinking to check
the win impl which didn't asset.
IOW, I think we need a prior patch that sets the 'errp'
in all these callers, either to &error_abort, or to
propage the error if practical.
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> Reviewed-by: Peter Xu <peterx@redhat.com>
> ---
> contrib/ivshmem-server/ivshmem-server.c | 6 +++++-
> hw/hyperv/syndbg.c | 4 +++-
> hw/virtio/vhost-user.c | 5 ++++-
> include/qemu/sockets.h | 1 -
> io/channel-socket.c | 7 +++----
> net/dgram.c | 16 +++++++++++++---
> net/l2tpv3.c | 5 +++--
> net/socket.c | 20 ++++++++++++++++----
> qga/channel-posix.c | 7 ++++++-
> tests/unit/socket-helpers.c | 5 ++++-
> tests/unit/test-crypto-tlssession.c | 8 ++++----
> util/oslib-posix.c | 7 -------
> util/oslib-win32.c | 5 -----
> util/vhost-user-server.c | 4 ++--
> 14 files changed, 63 insertions(+), 37 deletions(-)
>
> diff --git a/contrib/ivshmem-server/ivshmem-server.c b/contrib/ivshmem-server/ivshmem-server.c
> index 2f3c7320a6..a65943d0b8 100644
> --- a/contrib/ivshmem-server/ivshmem-server.c
> +++ b/contrib/ivshmem-server/ivshmem-server.c
> @@ -146,9 +146,13 @@ ivshmem_server_handle_new_conn(IvshmemServer *server)
> return -1;
> }
>
> - qemu_socket_set_nonblock(newfd);
> IVSHMEM_SERVER_DEBUG(server, "accept()=%d\n", newfd);
>
> + if (!qemu_set_blocking(newfd, false, NULL)) {
&error_warn here so we diagnose the reason we're returning -1
to the caller ?
> + close(newfd);
> + return -1;
> + }
> +
> /* allocate new structure for this peer */
> peer = g_malloc0(sizeof(*peer));
> peer->sock_fd = newfd;
> diff --git a/tests/unit/socket-helpers.c b/tests/unit/socket-helpers.c
> index 37db24f72a..1b7e283f24 100644
> --- a/tests/unit/socket-helpers.c
> +++ b/tests/unit/socket-helpers.c
> @@ -88,7 +88,10 @@ static int socket_can_bind_connect(const char *hostname, int family)
> goto cleanup;
> }
>
> - qemu_socket_set_nonblock(cfd);
> + if (!qemu_set_blocking(cfd, false, NULL)) {
&error_abort here.
> + goto cleanup;
> + }
> +
> if (connect(cfd, (struct sockaddr *)&ss, sslen) < 0) {
> if (errno == EINPROGRESS) {
> check_soerr = true;
With regards,
Daniel
--
|: https://berrange.com -o- https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org -o- https://fstop138.berrange.com :|
|: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|
On 12.09.25 19:59, Daniel P. Berrangé wrote: > On Thu, Sep 11, 2025 at 12:20:02PM +0300, Vladimir Sementsov-Ogievskiy wrote: >> Use common qemu_set_blocking() instead. >> >> Note that pre-patch the behavior of Win32 and Linux realizations >> are inconsistent: we ignore failure for Win32, and assert success >> for Linux. >> >> How do we convert the callers? >> 3. io/channel-socket.c: here we convert both old calls to >> qemu_socket_set_nonblock() and qemu_socket_set_block() to >> one new call. Pre-patch we assert success for Linux in >> qemu_socket_set_nonblock(), and ignore all other errors here. >> Still, all callers pass errp=NULL to qio_channel_set_blocking(), >> so after patch we ignore all errors. Switching from assertion >> to ignoring may be not very good, but still acceptable, keeping >> in mind that all callers of qio_channel_set_blocking() do >> explicitly ignore the error. > This is a bit questionable. IMHO the reason why nearly all > callers pass errp=NULL is laziness based on the assumption > that the code actually asserts, and no one thinking to check > the win impl which didn't asset. > > IOW, I think we need a prior patch that sets the 'errp' > in all these callers, either to &error_abort, or to > propage the error if practical. To be honest, I thought about it. I'll try. -- Best regards, Vladimir
On 12.09.25 19:59, Daniel P. Berrangé wrote:
> On Thu, Sep 11, 2025 at 12:20:02PM +0300, Vladimir Sementsov-Ogievskiy wrote:
>> Use common qemu_set_blocking() instead.
>>
>> Note that pre-patch the behavior of Win32 and Linux realizations
>> are inconsistent: we ignore failure for Win32, and assert success
>> for Linux.
>>
>> How do we convert the callers?
>
>> 3. io/channel-socket.c: here we convert both old calls to
>> qemu_socket_set_nonblock() and qemu_socket_set_block() to
>> one new call. Pre-patch we assert success for Linux in
>> qemu_socket_set_nonblock(), and ignore all other errors here.
>> Still, all callers pass errp=NULL to qio_channel_set_blocking(),
>> so after patch we ignore all errors. Switching from assertion
>> to ignoring may be not very good, but still acceptable, keeping
>> in mind that all callers of qio_channel_set_blocking() do
>> explicitly ignore the error.
>
> This is a bit questionable. IMHO the reason why nearly all
> callers pass errp=NULL is laziness based on the assumption
> that the code actually asserts, and no one thinking to check
> the win impl which didn't asset.
>
> IOW, I think we need a prior patch that sets the 'errp'
> in all these callers, either to &error_abort, or to
> propage the error if practical.
>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
>> Reviewed-by: Peter Xu <peterx@redhat.com>
>> ---
>> contrib/ivshmem-server/ivshmem-server.c | 6 +++++-
>> hw/hyperv/syndbg.c | 4 +++-
>> hw/virtio/vhost-user.c | 5 ++++-
>> include/qemu/sockets.h | 1 -
>> io/channel-socket.c | 7 +++----
>> net/dgram.c | 16 +++++++++++++---
>> net/l2tpv3.c | 5 +++--
>> net/socket.c | 20 ++++++++++++++++----
>> qga/channel-posix.c | 7 ++++++-
>> tests/unit/socket-helpers.c | 5 ++++-
>> tests/unit/test-crypto-tlssession.c | 8 ++++----
>> util/oslib-posix.c | 7 -------
>> util/oslib-win32.c | 5 -----
>> util/vhost-user-server.c | 4 ++--
>> 14 files changed, 63 insertions(+), 37 deletions(-)
>>
>> diff --git a/contrib/ivshmem-server/ivshmem-server.c b/contrib/ivshmem-server/ivshmem-server.c
>> index 2f3c7320a6..a65943d0b8 100644
>> --- a/contrib/ivshmem-server/ivshmem-server.c
>> +++ b/contrib/ivshmem-server/ivshmem-server.c
>> @@ -146,9 +146,13 @@ ivshmem_server_handle_new_conn(IvshmemServer *server)
>> return -1;
>> }
>>
>> - qemu_socket_set_nonblock(newfd);
>> IVSHMEM_SERVER_DEBUG(server, "accept()=%d\n", newfd);
>>
>> + if (!qemu_set_blocking(newfd, false, NULL)) {
>
> &error_warn here so we diagnose the reason we're returning -1
> to the caller ?
O, I missed we have error_warn already. It was always my dream to implement it, but never got around to it.
Ok
>
>> + close(newfd);
>> + return -1;
>> + }
>> +
>> /* allocate new structure for this peer */
>> peer = g_malloc0(sizeof(*peer));
>> peer->sock_fd = newfd;
>
>> diff --git a/tests/unit/socket-helpers.c b/tests/unit/socket-helpers.c
>> index 37db24f72a..1b7e283f24 100644
>> --- a/tests/unit/socket-helpers.c
>> +++ b/tests/unit/socket-helpers.c
>> @@ -88,7 +88,10 @@ static int socket_can_bind_connect(const char *hostname, int family)
>> goto cleanup;
>> }
>>
>> - qemu_socket_set_nonblock(cfd);
>> + if (!qemu_set_blocking(cfd, false, NULL)) {
>
> &error_abort here.
Ok
>
>> + goto cleanup;
>> + }
>> +
>> if (connect(cfd, (struct sockaddr *)&ss, sslen) < 0) {
>> if (errno == EINPROGRESS) {
>> check_soerr = true;
>
> With regards,
> Daniel
--
Best regards,
Vladimir
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