From: Mark Brown <broonie@kernel.org> As we do for pseudo NMIs don't call preempt_schedule_irq() when architechted NMIs are masked. If they are masked then we are calling from a preempting context so skip preemption. Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Jie Liu <liujie375@h-partners.com> --- arch/arm64/include/asm/sysreg.h | 3 +++ arch/arm64/kernel/process.c | 9 +++++++++ 2 files changed, 12 insertions(+) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 3da501312196..521f2c6cce86 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -202,6 +202,8 @@ #define SYS_SPSR_EL1 sys_reg(3, 0, 4, 0, 0) #define SYS_ELR_EL1 sys_reg(3, 0, 4, 0, 1) +#define SYS_ALLINT sys_reg(3, 0, 4, 3, 0) + #define SYS_ICC_PMR_EL1 sys_reg(3, 0, 4, 6, 0) #define SYS_AFSR0_EL1 sys_reg(3, 0, 5, 1, 0) @@ -226,6 +228,7 @@ #define ID_AA64PFR1_NMI_MASK GENMASK(39, 36) #define HCRX_EL2_TALLINT BIT(6) #define HCRX_EL2_TALLINT_MASK GENMASK(6, 6) +#define ALLINT_ALLINT BIT(13) /*** Statistical Profiling Extension ***/ /* ID registers */ diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 9bc43e35e87f..0b9193dff1e2 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -693,6 +693,15 @@ core_initcall(tagged_addr_init); asmlinkage void __sched arm64_preempt_schedule_irq(void) { + /* + * Architected NMIs are unmasked prior to handling regular + * IRQs and masked while handling FIQs. If ALLINT is set then + * we are in a NMI or other preempting context so skip + * preemption. + */ + if (system_uses_nmi() && (read_sysreg_s(SYS_ALLINT) & ALLINT_ALLINT)) + return; + lockdep_assert_irqs_disabled(); /* -- 2.25.1