diff options
authorGuenter Roeck <linux@roeck-us.net>2020-08-07 07:45:21 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-08-11 15:35:42 +0200
commitab5dd525532ea1246395c88337b9451224874a60 (patch)
parent4efe0ff1c84660710d45e00a52d07a1d9fde0de7 (diff)
arm64: kaslr: Use standard early random function
commit 9bceb80b3cc483e6763c39a4928402fa82815d3e upstream. Commit 585524081ecd ("random: random.h should include archrandom.h, not the other way around") tries to fix a problem with recursive inclusion of linux/random.h and arch/archrandom.h for arm64. Unfortunately, this results in the following compile error if ARCH_RANDOM is disabled. arch/arm64/kernel/kaslr.c: In function 'kaslr_early_init': arch/arm64/kernel/kaslr.c:128:6: error: implicit declaration of function '__early_cpu_has_rndr'; did you mean '__early_pfn_to_nid'? [-Werror=implicit-function-declaration] if (__early_cpu_has_rndr()) { ^~~~~~~~~~~~~~~~~~~~ __early_pfn_to_nid arch/arm64/kernel/kaslr.c:131:7: error: implicit declaration of function '__arm64_rndr' [-Werror=implicit-function-declaration] if (__arm64_rndr(&raw)) ^~~~~~~~~~~~ The problem is that arch/archrandom.h is only included from linux/random.h if ARCH_RANDOM is enabled. If not, __arm64_rndr() and __early_cpu_has_rndr() are undeclared, causing the problem. Use arch_get_random_seed_long_early() instead of arm64 specific functions to solve the problem. Reported-by: Qian Cai <cai@lca.pw> Fixes: 585524081ecd ("random: random.h should include archrandom.h, not the other way around") Cc: Qian Cai <cai@lca.pw> Cc: Mark Brown <broonie@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Mark Brown <broonie@kernel.org> Tested-by: Mark Brown <broonie@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Sedat Dilek <sedat.dilek@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1 files changed, 5 insertions, 7 deletions
diff --git a/arch/arm64/kernel/kaslr.c b/arch/arm64/kernel/kaslr.c
index e2101440c314..b892670293a9 100644
--- a/arch/arm64/kernel/kaslr.c
+++ b/arch/arm64/kernel/kaslr.c
@@ -84,6 +84,7 @@ u64 __init kaslr_early_init(u64 dt_phys)
void *fdt;
u64 seed, offset, mask, module_range;
const u8 *cmdline, *str;
+ unsigned long raw;
int size;
@@ -122,15 +123,12 @@ u64 __init kaslr_early_init(u64 dt_phys)
- * Mix in any entropy obtainable architecturally, open coded
- * since this runs extremely early.
+ * Mix in any entropy obtainable architecturally if enabled
+ * and supported.
- if (__early_cpu_has_rndr()) {
- unsigned long raw;
- if (__arm64_rndr(&raw))
- seed ^= raw;
- }
+ if (arch_get_random_seed_long_early(&raw))
+ seed ^= raw;
if (!seed) {
kaslr_status = KASLR_DISABLED_NO_SEED;