similar to: [PATCH v3] virtio-rng: return available data with O_NONBLOCK

On 28/08/2020 23:34, Martin Wilck wrote: > On Wed, 2020-08-26 at 08:26 -0400, Michael S. Tsirkin wrote: >> On Tue, Aug 11, 2020 at 04:42:32PM +0200, Laurent Vivier wrote: >>> On 11/08/2020 16:28, mwilck at suse.com wrote: >>>> From: Martin Wilck <mwilck at suse.com> >>>> >>>> If a program opens /dev/hwrng with O_NONBLOCK and uses poll()

On Wed, Jul 15, 2020 at 03:32:55PM +0200, mwilck at suse.com wrote: > From: Martin Wilck <mwilck at suse.com> > > If a program opens /dev/hwrng with O_NONBLOCK and uses poll() and > non-blocking read() to retrieve random data, it ends up in a tight > loop with poll() always returning POLLIN and read() returning EAGAIN. > This repeats forever until some process makes a

On 11/08/2020 12:37, Philippe Mathieu-Daud? wrote: > You Cc'ed qemu-devel, so Cc'ing the virtio-rng maintainers. > > On 7/15/20 3:32 PM, mwilck at suse.com wrote: >> From: Martin Wilck <mwilck at suse.com> >> >> If a program opens /dev/hwrng with O_NONBLOCK and uses poll() and >> non-blocking read() to retrieve random data, it ends up in a tight

On 11/08/2020 14:53, Martin Wilck wrote: > On Tue, 2020-08-11 at 14:39 +0200, Laurent Vivier wrote: >> On 11/08/2020 14:22, Martin Wilck wrote: >>> On Tue, 2020-08-11 at 14:02 +0200, Laurent Vivier wrote: >>>>>> drivers/char/hw_random/virtio-rng.c | 14 ++++++++++++++ >>>>>> 1 file changed, 14 insertions(+) >>>>>>

On 11/08/2020 14:53, Martin Wilck wrote: > On Tue, 2020-08-11 at 14:39 +0200, Laurent Vivier wrote: >> On 11/08/2020 14:22, Martin Wilck wrote: >>> On Tue, 2020-08-11 at 14:02 +0200, Laurent Vivier wrote: >>>>>> drivers/char/hw_random/virtio-rng.c | 14 ++++++++++++++ >>>>>> 1 file changed, 14 insertions(+) >>>>>>

On 11/08/2020 15:14, Michael S. Tsirkin wrote: > On Tue, Aug 11, 2020 at 03:00:14PM +0200, Laurent Vivier wrote: >> No problem. This code is tricky and it took me several months to really >> start to understand it ... > > Oh great, we actually have someone who understands the code! > Maybe you can help me understand: virtio_read > takes the buf pointer and puts it in

On 11/08/2020 15:14, Michael S. Tsirkin wrote: > On Tue, Aug 11, 2020 at 03:00:14PM +0200, Laurent Vivier wrote: >> No problem. This code is tricky and it took me several months to really >> start to understand it ... > > Oh great, we actually have someone who understands the code! > Maybe you can help me understand: virtio_read > takes the buf pointer and puts it in

Current hwrng core supports to register multiple hwrng devices, and there is only one device really works in the same time. QEMU alsu supports to have multiple virtio-rng backends. This patch changes virtio-rng driver to support multiple virtio-rng devices. ]# cat /sys/class/misc/hw_random/rng_available virtio_rng.0 virtio_rng.1 ]# cat /sys/class/misc/hw_random/rng_current virtio_rng.0 ]# echo

Current hwrng core supports to register multiple hwrng devices, and there is only one device really works in the same time. QEMU alsu supports to have multiple virtio-rng backends. This patch changes virtio-rng driver to support multiple virtio-rng devices. ]# cat /sys/class/misc/hw_random/rng_available virtio_rng.0 virtio_rng.1 ]# cat /sys/class/misc/hw_random/rng_current virtio_rng.0 ]# echo

Hi Rusty, These are a few fixes for the virtio-rng driver. These were tested using the not-yet-upstream virtio-rng device patch to qemu: http://thread.gmane.org/gmane.comp.emulators.qemu/152668 Please apply. Amit Shah (5): virtio ids: fix comment for virtio-rng virtio: rng: allow tasks to be killed that are waiting for rng input virtio: rng: don't wait on host when module is going

Hi Rusty, These are a few fixes for the virtio-rng driver. These were tested using the not-yet-upstream virtio-rng device patch to qemu: http://thread.gmane.org/gmane.comp.emulators.qemu/152668 Please apply. Amit Shah (5): virtio ids: fix comment for virtio-rng virtio: rng: allow tasks to be killed that are waiting for rng input virtio: rng: don't wait on host when module is going

On (Wed) 06 Aug 2014 [16:05:41], Amos Kong wrote: > On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > > the device can't be hot-removed. Because virtio-rng driver hangs at > > wait_for_completion_killable(). > > > > This patch fixed the hang by completing have_data completion

On (Wed) 06 Aug 2014 [16:05:41], Amos Kong wrote: > On Wed, Aug 06, 2014 at 01:35:15AM +0800, Amos Kong wrote: > > When we try to hot-remove a busy virtio-rng device from QEMU monitor, > > the device can't be hot-removed. Because virtio-rng driver hangs at > > wait_for_completion_killable(). > > > > This patch fixed the hang by completing have_data completion

v2: - this now separates both the patches; the virtio-rng fix is self-contained - re-work hwrng core to fetch randomness at device init time if ->init() is registered by the device, instead of not calling it at all. - virtio-rng: introduce a probe_done bool to ensure we don't ask host for data before successful probe Hi, When booting a recent kernel under KVM with the virtio-rng

v2: - this now separates both the patches; the virtio-rng fix is self-contained - re-work hwrng core to fetch randomness at device init time if ->init() is registered by the device, instead of not calling it at all. - virtio-rng: introduce a probe_done bool to ensure we don't ask host for data before successful probe Hi, When booting a recent kernel under KVM with the virtio-rng

A bit late to a party, but: On Mon, Dec 8, 2014 at 12:50 AM, Amos Kong <akong at redhat.com> wrote: > From: Rusty Russell <rusty at rustcorp.com.au> > > There's currently a big lock around everything, and it means that we > can't query sysfs (eg /sys/devices/virtual/misc/hw_random/rng_current) > while the rng is reading. This is a real problem when the rng is

A bit late to a party, but: On Mon, Dec 8, 2014 at 12:50 AM, Amos Kong <akong at redhat.com> wrote: > From: Rusty Russell <rusty at rustcorp.com.au> > > There's currently a big lock around everything, and it means that we > can't query sysfs (eg /sys/devices/virtual/misc/hw_random/rng_current) > while the rng is reading. This is a real problem when the rng is

Hi, This series enables virtio-rng to service the early randomness requests made by the hwrng core (patch 2), with Herbert's idea of using the scan routine. Patch 3 reverts the previous restriction, which no longer applies, to not send read requests to the host before successful probe. Patch 1 is a minor cleanup. Please review and apply, Amit Shah (3): virtio: rng: remove unused struct

Hi, This series enables virtio-rng to service the early randomness requests made by the hwrng core (patch 2), with Herbert's idea of using the scan routine. Patch 3 reverts the previous restriction, which no longer applies, to not send read requests to the host before successful probe. Patch 1 is a minor cleanup. Please review and apply, Amit Shah (3): virtio: rng: remove unused struct

Hello, This series introduces a way to allow devices to contribute to initial system randomness after a certain delay. Specifically, the virtio-rng device can contribute initial randomness only after a successful probe(). A delayed workqueue item is queued in the system queue to fetch this randomness if the device indicates it's capable of contributing only after a delay, via the new