search for: add_device_randomness

...rivers/char/hw_random/core.c > @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) > INIT_LIST_HEAD(&rng->list); > list_add_tail(&rng->list, &rng_list); > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > - if (bytes_read > 0) > - add_device_randomness(bytes, bytes_read); > + if (!rng->init) { > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > + if (bytes_read > 0) > + add_device_randomness(bytes, bytes_read); > + } afaict, this is redundant at initialization time. current_rng shouldn't be set yet, so hw...

...rivers/char/hw_random/core.c > @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) > INIT_LIST_HEAD(&rng->list); > list_add_tail(&rng->list, &rng_list); > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > - if (bytes_read > 0) > - add_device_randomness(bytes, bytes_read); > + if (!rng->init) { > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > + if (bytes_read > 0) > + add_device_randomness(bytes, bytes_read); > + } afaict, this is redundant at initialization time. current_rng shouldn't be set yet, so hw...

Hi, When booting a recent kernel under KVM with the virtio-rng device enabled, the boot process was stalling. Bisect pointed to a commit made during the 3.15 window to fetch randomness from newly-registered devices in the hwrng core. The details are in the patches. I considered a couple of approaches, but basing on the init() function being registered, as is done in patch 1 here, seems like

Hi, When booting a recent kernel under KVM with the virtio-rng device enabled, the boot process was stalling. Bisect pointed to a commit made during the 3.15 window to fetch randomness from newly-registered devices in the hwrng core. The details are in the patches. I considered a couple of approaches, but basing on the init() function being registered, as is done in patch 1 here, seems like

...gt; @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) > > INIT_LIST_HEAD(&rng->list); > > list_add_tail(&rng->list, &rng_list); > > > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > - if (bytes_read > 0) > > - add_device_randomness(bytes, bytes_read); > > + if (!(rng->flags & HWRNG_NO_READ_AT_PROBE)) { > > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > + if (bytes_read > 0) > > + add_device_randomness(bytes, bytes_read); > > + } > > But this has the inverse pr...

...gt; @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) > > INIT_LIST_HEAD(&rng->list); > > list_add_tail(&rng->list, &rng_list); > > > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > - if (bytes_read > 0) > > - add_device_randomness(bytes, bytes_read); > > + if (!(rng->flags & HWRNG_NO_READ_AT_PROBE)) { > > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > + if (bytes_read > 0) > > + add_device_randomness(bytes, bytes_read); > > + } > > But this has the inverse pr...

...ivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) INIT_LIST_HEAD(&rng->list); list_add_tail(&rng->list, &rng_list); - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); - if (bytes_read > 0) - add_device_randomness(bytes, bytes_read); + if (!(rng->flags & HWRNG_NO_READ_AT_PROBE)) { + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); + if (bytes_read > 0) + add_device_randomness(bytes, bytes_read); + } out_unlock: mutex_unlock(&rng_mutex); out: diff --git a/include/linux/hw_random....

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

...gt; @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) > > INIT_LIST_HEAD(&rng->list); > > list_add_tail(&rng->list, &rng_list); > > > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > - if (bytes_read > 0) > > - add_device_randomness(bytes, bytes_read); > > + if (!rng->init) { > > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > + if (bytes_read > 0) > > + add_device_randomness(bytes, bytes_read); > > + } > > afaict, this is redundant at initialization time. current_...

...rivers/char/hw_random/core.c > @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) > INIT_LIST_HEAD(&rng->list); > list_add_tail(&rng->list, &rng_list); > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > - if (bytes_read > 0) > - add_device_randomness(bytes, bytes_read); > + if (!(rng->flags & HWRNG_NO_READ_AT_PROBE)) { > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > + if (bytes_read > 0) > + add_device_randomness(bytes, bytes_read); > + } But this has the inverse problem: if there are two hwrngs in t...

...ivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -347,9 +347,11 @@ int hwrng_register(struct hwrng *rng) INIT_LIST_HEAD(&rng->list); list_add_tail(&rng->list, &rng_list); - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); - if (bytes_read > 0) - add_device_randomness(bytes, bytes_read); + if (!rng->init) { + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); + if (bytes_read > 0) + add_device_randomness(bytes, bytes_read); + } out_unlock: mutex_unlock(&rng_mutex); out: -- 1.9.3

...ait); + static size_t rng_buffer_size(void) { return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES; } +static void add_early_randomness(struct hwrng *rng) +{ + unsigned char bytes[16]; + int bytes_read; + + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); + if (bytes_read > 0) + add_device_randomness(bytes, bytes_read); +} + static inline int hwrng_init(struct hwrng *rng) { + int ret; + if (!rng->init) return 0; - return rng->init(rng); + + ret = rng->init(rng); + if (ret) + return ret; + + add_early_randomness(rng); + return ret; } static inline void hwrng_cleanup(struct...

...ait); + static size_t rng_buffer_size(void) { return SMP_CACHE_BYTES < 32 ? 32 : SMP_CACHE_BYTES; } +static void add_early_randomness(struct hwrng *rng) +{ + unsigned char bytes[16]; + int bytes_read; + + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); + if (bytes_read > 0) + add_device_randomness(bytes, bytes_read); +} + static inline int hwrng_init(struct hwrng *rng) { - if (!rng->init) - return 0; - return rng->init(rng); + if (rng->init) { + int ret; + + ret = rng->init(rng); + if (ret) + return ret; + } + add_early_randomness(rng); + return 0; } static inline vo...

...32 : SMP_CACHE_BYTES; > } > > -static void add_early_randomness(struct hwrng *rng) > +static void get_early_randomness(struct hwrng *rng) > { > unsigned char bytes[16]; > int bytes_read; > @@ -79,6 +79,21 @@ static void add_early_randomness(struct hwrng *rng) > add_device_randomness(bytes, bytes_read); > } > > +static void sched_init_random(struct work_struct *work) > +{ > + struct hwrng *rng = container_of(work, struct hwrng, dwork.work); > + > + get_early_randomness(rng); > +} > + > +static void add_early_randomness(struct hwrng *rng) The ad...

...ster(struct hwrng *rng) >> > INIT_LIST_HEAD(&rng->list); >> > list_add_tail(&rng->list, &rng_list); >> > >> > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); >> > - if (bytes_read > 0) >> > - add_device_randomness(bytes, bytes_read); >> > + if (!(rng->flags & HWRNG_NO_READ_AT_PROBE)) { >> > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); >> > + if (bytes_read > 0) >> > + add_device_randomness(bytes, bytes_read);...

...32 : SMP_CACHE_BYTES; > } > > -static void add_early_randomness(struct hwrng *rng) > +static void get_early_randomness(struct hwrng *rng) > { > unsigned char bytes[16]; > int bytes_read; > @@ -79,6 +79,21 @@ static void add_early_randomness(struct hwrng *rng) > add_device_randomness(bytes, bytes_read); > } > > +static void sched_init_random(struct work_struct *work) > +{ > + struct hwrng *rng = container_of(work, struct hwrng, dwork.work); > + > + get_early_randomness(rng); > +} > + > +static void add_early_randomness(struct hwrng *rng) The ad...

...wrng_register(struct hwrng *rng) > > > INIT_LIST_HEAD(&rng->list); > > > list_add_tail(&rng->list, &rng_list); > > > > > > - bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > > - if (bytes_read > 0) > > > - add_device_randomness(bytes, bytes_read); > > > + if (!(rng->flags & HWRNG_NO_READ_AT_PROBE)) { > > > + bytes_read = rng_get_data(rng, bytes, sizeof(bytes), 1); > > > + if (bytes_read > 0) > > > + add_device_randomness(bytes, bytes_read); > > > + } > > &g...

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

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