diff options
Diffstat (limited to 'drivers/char/random.c')
| -rw-r--r-- | drivers/char/random.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 87fe61295ea1..c12f906e05d6 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -281,8 +281,15 @@ static void crng_reseed(struct work_struct *work) * former to arrive at the latter. Use smp_store_release so that this * is ordered with the write above to base_crng.generation. Pairs with * the smp_rmb() before the syscall in the vDSO code. + * + * Cast to unsigned long for 32-bit architectures, since atomic 64-bit + * operations are not supported on those architectures. This is safe + * because base_crng.generation is a 32-bit value. On big-endian + * architectures it will be stored in the upper 32 bits, but that's okay + * because the vDSO side only checks whether the value changed, without + * actually using or interpreting the value. */ - smp_store_release(&_vdso_rng_data.generation, next_gen + 1); + smp_store_release((unsigned long *)&_vdso_rng_data.generation, next_gen + 1); #endif if (!static_branch_likely(&crng_is_ready)) crng_init = CRNG_READY; |