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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-07-26 20:03:53 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-07-26 20:03:53 +0300 |
| commit | 5de64d44968e4ae66ebdb0a2d08b443f189d3651 (patch) | |
| tree | cb77a416574ee71ec0d09c01e7d6239408d4ba34 | |
| parent | cdb281e63874086a650552d36c504ea717a0e0cb (diff) | |
| parent | 918e75f77af7d2e049bb70469ec0a2c12782d96a (diff) | |
| download | linux-5de64d44968e4ae66ebdb0a2d08b443f189d3651.tar.xz | |
Merge tag 's390-5.19-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fix from Alexander GordeevL
- Prevent relatively slow PRNO TRNG random number operation from being
called from interrupt context. That could for example cause some
network loads to timeout.
* tag 's390-5.19-7' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/archrandom: prevent CPACF trng invocations in interrupt context
| -rw-r--r-- | arch/s390/include/asm/archrandom.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/s390/include/asm/archrandom.h b/arch/s390/include/asm/archrandom.h index 2c6e1c6ecbe7..4120c428dc37 100644 --- a/arch/s390/include/asm/archrandom.h +++ b/arch/s390/include/asm/archrandom.h @@ -2,7 +2,7 @@ /* * Kernel interface for the s390 arch_random_* functions * - * Copyright IBM Corp. 2017, 2020 + * Copyright IBM Corp. 2017, 2022 * * Author: Harald Freudenberger <freude@de.ibm.com> * @@ -14,6 +14,7 @@ #ifdef CONFIG_ARCH_RANDOM #include <linux/static_key.h> +#include <linux/preempt.h> #include <linux/atomic.h> #include <asm/cpacf.h> @@ -32,7 +33,8 @@ static inline bool __must_check arch_get_random_int(unsigned int *v) static inline bool __must_check arch_get_random_seed_long(unsigned long *v) { - if (static_branch_likely(&s390_arch_random_available)) { + if (static_branch_likely(&s390_arch_random_available) && + in_task()) { cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v)); atomic64_add(sizeof(*v), &s390_arch_random_counter); return true; @@ -42,7 +44,8 @@ static inline bool __must_check arch_get_random_seed_long(unsigned long *v) static inline bool __must_check arch_get_random_seed_int(unsigned int *v) { - if (static_branch_likely(&s390_arch_random_available)) { + if (static_branch_likely(&s390_arch_random_available) && + in_task()) { cpacf_trng(NULL, 0, (u8 *)v, sizeof(*v)); atomic64_add(sizeof(*v), &s390_arch_random_counter); return true; |