From e1e3a0ab69c64eedaf53dce9306f8a090bf038f0 Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Wed, 19 Aug 2026 14:43:21 -0700 Subject: [PATCH] ARM: Fix get_cycles() after delay_read_timer() conversion After commit dfc256dac54c ("calibrate: Rework delay timer calibration"), certain ARM configurations (such as multi_v5_defconfig) hang during boot. The use of read_current_timer() in arch/arm's get_cycles() was improperly converted to delay_read_timer(), resulting in get_cycles() returning 0 even when the timer has been read or an uninitialized stack value when delay_read_timer() returns false. Flip the branches of the ternary condition to fix get_cycles(). Fixes: dfc256dac54c ("calibrate: Rework delay timer calibration") Signed-off-by: Nathan Chancellor Signed-off-by: Thomas Gleixner Reviewed-by: Jinjie Ruan Cc: Thomas Gleixner Cc: linux-arm-kernel@lists.infradead.org Link: https://patch.msgid.link/20260819-fix-arm-get_cycles-v1-1-208bf07ac540@kernel.org --- arch/arm/include/asm/timex.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/include/asm/timex.h b/arch/arm/include/asm/timex.h index 94e40c19cfc5..4d31eab9dba2 100644 --- a/arch/arm/include/asm/timex.h +++ b/arch/arm/include/asm/timex.h @@ -13,7 +13,7 @@ typedef unsigned long cycles_t; // Temporary workaround until timex.h is cleaned up bool delay_read_timer(unsigned long *t); -#define get_cycles() ({ cycles_t c; delay_read_timer(&c) ? 0 : c; }) +#define get_cycles() ({ cycles_t c; delay_read_timer(&c) ? c : 0; }) #define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback()) #endif