search for: hw_random

...g only after a delay, via the new HWRNG_DELAY_READ_AT_INIT flag. This series is intended for the next merge window. I've marked it as RFC because the last revert doesn't yet have a linux.git sha1. I'll re-post when the previous series gets committed. Please review, Amit Shah (3): hw_random: allow RNG devices to give early randomness after a delay virtio: rng: only accept delayed early randomness requests Revert "virtio: rng: ensure reads happen after successful probe" drivers/char/hw_random/core.c | 26 +++++++++++++++++++------- drivers/char/hw_random/virtio-rn...

...g only after a delay, via the new HWRNG_DELAY_READ_AT_INIT flag. This series is intended for the next merge window. I've marked it as RFC because the last revert doesn't yet have a linux.git sha1. I'll re-post when the previous series gets committed. Please review, Amit Shah (3): hw_random: allow RNG devices to give early randomness after a delay virtio: rng: only accept delayed early randomness requests Revert "virtio: rng: ensure reads happen after successful probe" drivers/char/hw_random/core.c | 26 +++++++++++++++++++------- drivers/char/hw_random/virtio-rn...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V5: reset cleanup_done...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V5: reset cleanup_done...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V4: update patch 4 to...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V4: update patch 4 to...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V5: reset cleanup_done...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V5: reset cleanup_done...

...host before successful probe. Patch 1 is a minor cleanup. Please review and apply, Amit Shah (3): virtio: rng: remove unused struct element virtio: rng: delay hwrng_register() till driver is ready Revert "hwrng: virtio - ensure reads happen after successful probe" drivers/char/hw_random/core.c | 6 ------ drivers/char/hw_random/virtio-rng.c | 35 +++++++++++++++-------------------- 2 files changed, 15 insertions(+), 26 deletions(-) -- 1.9.3

...host before successful probe. Patch 1 is a minor cleanup. Please review and apply, Amit Shah (3): virtio: rng: remove unused struct element virtio: rng: delay hwrng_register() till driver is ready Revert "hwrng: virtio - ensure reads happen after successful probe" drivers/char/hw_random/core.c | 6 ------ drivers/char/hw_random/virtio-rng.c | 35 +++++++++++++++-------------------- 2 files changed, 15 insertions(+), 26 deletions(-) -- 1.9.3

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V2: added patch 2 to f...

...test 1: | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 2: | guest) # dd if=/dev/random of=/dev/null & | hotunplug rng device from qemu monitor | | test 4: | guest) # dd if=/dev/hwrng of=/dev/null & | cat /sys/devices/virtual/misc/hw_random/rng_* | | test 5: | guest) # dd if=/dev/hwrng of=/dev/null | cancel dd process after 10 seconds | guest) # dd if=/dev/hwrng of=/dev/null & | hotunplug rng device from qemu monitor | | test 6: | use a fifo as rng backend, execute test 0 ~ 5 with no input of fifo V2: added patch 2 to f...

...at redhat.com> writes: > I started a QEMU (non-smp) guest with one virtio-rng device, and read > random data from /dev/hwrng by dd: > > # dd if=/dev/hwrng of=/dev/null & > > In the same time, if I check hwrng attributes from sysfs by cat: > > # cat /sys/class/misc/hw_random/rng_* > > The cat process always gets stuck with slow backend (5 k/s), if we > use a quick backend (1.2 M/s), the cat process will cost 1 to 2 > minutes. The stuck doesn't exist for smp guest. > > Reading syscall enters kernel and call rng_dev_read(), it's user > contex...

...at redhat.com> writes: > I started a QEMU (non-smp) guest with one virtio-rng device, and read > random data from /dev/hwrng by dd: > > # dd if=/dev/hwrng of=/dev/null & > > In the same time, if I check hwrng attributes from sysfs by cat: > > # cat /sys/class/misc/hw_random/rng_* > > The cat process always gets stuck with slow backend (5 k/s), if we > use a quick backend (1.2 M/s), the cat process will cost 1 to 2 > minutes. The stuck doesn't exist for smp guest. > > Reading syscall enters kernel and call rng_dev_read(), it's user > contex...

...) to always schedule 10 jiffies after release mutex lock, then cat process can have chance to get the lock and execute protected code without stuck. Thanks. V2: update commitlog to describe PATCH 2, split second patch. Amos Kong (3): virtio-rng cleanup: move some code out of mutex protection hw_random: fix stuck in catting hwrng attributes hw_random: increase schedule timeout in rng_dev_read() drivers/char/hw_random/core.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) -- 1.9.3

...) to always schedule 10 jiffies after release mutex lock, then cat process can have chance to get the lock and execute protected code without stuck. Thanks. V2: update commitlog to describe PATCH 2, split second patch. Amos Kong (3): virtio-rng cleanup: move some code out of mutex protection hw_random: fix stuck in catting hwrng attributes hw_random: increase schedule timeout in rng_dev_read() drivers/char/hw_random/core.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) -- 1.9.3

...re, seems like the best idea, since quite a few drivers need to initialize their devices before data is fetched off them. Please review and apply if appropriate, Amit Shah (2): hwrng: don't fetch rng from sources without init virtio: rng: introduce an init fn for hwrng core drivers/char/hw_random/core.c | 8 +++++--- drivers/char/hw_random/virtio-rng.c | 11 +++++++++++ 2 files changed, 16 insertions(+), 3 deletions(-) -- 1.9.3

...core. The second bug is virtio can't communicate with the host without the device probe is successfully completed. Please review and apply if appropriate, Amit Shah (2): hwrng: fetch randomness only after device init virtio: rng: ensure reads happen after successful probe drivers/char/hw_random/core.c | 37 +++++++++++++++++++++++++++++++------ drivers/char/hw_random/virtio-rng.c | 10 ++++++++++ 2 files changed, 41 insertions(+), 6 deletions(-) -- 1.9.3

...re, seems like the best idea, since quite a few drivers need to initialize their devices before data is fetched off them. Please review and apply if appropriate, Amit Shah (2): hwrng: don't fetch rng from sources without init virtio: rng: introduce an init fn for hwrng core drivers/char/hw_random/core.c | 8 +++++--- drivers/char/hw_random/virtio-rng.c | 11 +++++++++++ 2 files changed, 16 insertions(+), 3 deletions(-) -- 1.9.3

...core. The second bug is virtio can't communicate with the host without the device probe is successfully completed. Please review and apply if appropriate, Amit Shah (2): hwrng: fetch randomness only after device init virtio: rng: ensure reads happen after successful probe drivers/char/hw_random/core.c | 37 +++++++++++++++++++++++++++++++------ drivers/char/hw_random/virtio-rng.c | 10 ++++++++++ 2 files changed, 41 insertions(+), 6 deletions(-) -- 1.9.3