From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:35655) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1goXf6-0004tN-3q for qemu-devel@nongnu.org; Tue, 29 Jan 2019 12:59:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1goXf5-0002OY-AK for qemu-devel@nongnu.org; Tue, 29 Jan 2019 12:59:04 -0500 From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= Date: Tue, 29 Jan 2019 18:53:58 +0100 Message-Id: <20190129175403.18017-14-philmd@redhat.com> In-Reply-To: <20190129175403.18017-1-philmd@redhat.com> References: <20190129175403.18017-1-philmd@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] [RFC PATCH v2 13/18] oslib-posix: Ignore fcntl("/dev/null", F_SETFL, O_NONBLOCK) failure List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Brad Smith , qemu-devel@nongnu.org Cc: Stefan Hajnoczi , qemu-block@nongnu.org, Igor Mammedov , Paolo Bonzini , Eric Blake , Peter Maydell , =?UTF-8?q?Alex=20Benn=C3=A9e?= , Kevin Wolf , Max Reitz , Markus Armbruster , Fam Zheng , =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , "Michael S. Tsirkin" , Kamil Rytarowski Previous to OpenBSD 6.3 [1], fcntl(F_SETFL) is not permitted on memory devices. Trying this call sets errno to ENODEV ("not a memory device"): 19 ENODEV Operation not supported by device. An attempt was made to apply an inappropriate function to a device, for example, trying to read a write-only device such as a printer. Do not assert fcntl failures in this specific case (errno set to ENODEV) on OpenBSD. This fixes: $ lm32-softmmu/qemu-system-lm32 assertion "f !=3D -1" failed: file "util/oslib-posix.c", line 247, func= tion "qemu_set_nonblock" Abort trap (core dumped) [1] The fix seems https://github.com/openbsd/src/commit/c2a35b387f9d3c "fcntl(F_SETFL) invokes the FIONBIO and FIOASYNC ioctls internally, so the memory devices (/dev/null, /dev/zero, etc) need to permit them." Signed-off-by: Philippe Mathieu-Daud=C3=A9 --- util/oslib-posix.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/util/oslib-posix.c b/util/oslib-posix.c index 4ce1ba9ca4..2f0f27e6d9 100644 --- a/util/oslib-posix.c +++ b/util/oslib-posix.c @@ -244,7 +244,17 @@ void qemu_set_nonblock(int fd) f =3D fcntl(fd, F_GETFL); assert(f !=3D -1); f =3D fcntl(fd, F_SETFL, f | O_NONBLOCK); +#ifdef __OpenBSD__ + if (f =3D=3D -1) { + /* + * Previous to OpenBSD 6.3, fcntl(F_SETFL) is not permitted on + * memory devices and sets errno to ENODEV. + */ + assert(errno =3D=3D ENODEV); + } +#else assert(f !=3D -1); +#endif } =20 int socket_set_fast_reuse(int fd) --=20 2.20.1