[PATCH v8 13/26] arm64: daifflags: Include PMR in daifflags restore operations
From: Julien Thierry <hidden>
Date: 2019-01-08 14:09:53
Also in:
lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
The addition of PMR should not bypass the semantics of daifflags. When DA_F are set, I bit is also set as no interrupts (even of higher priority) is allowed. When DA_F are cleared, I bit is cleared and interrupt enabling/disabling goes through ICC_PMR_EL1. Signed-off-by: Julien Thierry <redacted> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <redacted> Cc: James Morse <james.morse@arm.com> --- arch/arm64/include/asm/daifflags.h | 31 +++++++++++++++++++++++++++---- 1 file changed, 27 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/asm/daifflags.h b/arch/arm64/include/asm/daifflags.h
index 546bc39..1fd390e 100644
--- a/arch/arm64/include/asm/daifflags.h
+++ b/arch/arm64/include/asm/daifflags.h@@ -18,6 +18,8 @@ #include <linux/irqflags.h> +#include <asm/cpufeature.h> + #define DAIF_PROCCTX 0 #define DAIF_PROCCTX_NOIRQ PSR_I_BIT
@@ -36,7 +38,13 @@ static inline unsigned long local_daif_save(void) { unsigned long flags; - flags = arch_local_save_flags(); + flags = read_sysreg(daif); + + if (system_uses_irq_prio_masking()) { + /* If IRQs are masked with PMR, reflect it in the flags */ + if (read_sysreg_s(SYS_ICC_PMR_EL1) <= GIC_PRIO_IRQOFF) + flags |= PSR_I_BIT; + } local_daif_mask();
@@ -45,12 +53,27 @@ static inline unsigned long local_daif_save(void) static inline void local_daif_restore(unsigned long flags) { - if (!arch_irqs_disabled_flags(flags)) + bool irq_disabled = flags & PSR_I_BIT; + + if (!irq_disabled) { trace_hardirqs_on(); - arch_local_irq_restore(flags); + if (system_uses_irq_prio_masking()) + arch_local_irq_enable(); + } else if (!(flags & PSR_A_BIT)) { + /* + * If interrupts are disabled but we can take + * asynchronous errors, we can take NMIs + */ + if (system_uses_irq_prio_masking()) { + flags &= ~PSR_I_BIT; + arch_local_irq_disable(); + } + } + + write_sysreg(flags, daif); - if (arch_irqs_disabled_flags(flags)) + if (irq_disabled) trace_hardirqs_off(); }
--
1.9.1
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