| Message ID | 20240618103803.40578-1-luxu.kernel@bytedance.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | riscv: Fix local irq restore when flags indicates irq disabled | expand |
On Tue, Jun 18, 2024 at 06:38:03PM +0800, Xu Lu wrote: > When arch_local_irq_restore() is called with flags indicating irqs > disabled, we need to clear SR_IE bit in CSR_STATUS, whereas current > implementation based on csr_set() function only sets SR_IE bit of > CSR_STATUS when SR_IE bit of flags is high and does nothing when > SR_IE bit of flags is low. That shouldn't matter; arch_local_irq_restore() should *never* be called from a context with IRQs enabled, and so arch_local_irq_restore() never needs to disable IRQs. Either it enables IRQs or it leaves IRQs disabled, but it never needs to explicitly disable IRQs. See CONFIG_DEBUG_IRQFLAGS and the commit that introduced it: 997acaf6b4b59c6a ("lockdep: report broken irq restoration") I don't believe this patch is necessary. Mark. > > This commit supplies csr clear operation when calling irq restore > function with flags indicating irq disabled. > > Fixes: 6d60b6ee0c97 ("RISC-V: Device, timer, IRQs, and the SBI") > Signed-off-by: Xu Lu <luxu.kernel@bytedance.com> > --- > arch/riscv/include/asm/irqflags.h | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/arch/riscv/include/asm/irqflags.h b/arch/riscv/include/asm/irqflags.h > index 6fd8cbfcfcc7..f3aad7bfadb7 100644 > --- a/arch/riscv/include/asm/irqflags.h > +++ b/arch/riscv/include/asm/irqflags.h > @@ -48,7 +48,10 @@ static inline int arch_irqs_disabled(void) > /* set interrupt enabled status */ > static inline void arch_local_irq_restore(unsigned long flags) > { > - csr_set(CSR_STATUS, flags & SR_IE); > + if (flags & SR_IE) > + csr_set(CSR_STATUS, SR_IE); > + else > + csr_clear(CSR_STATUS, SR_IE); > } > > #endif /* _ASM_RISCV_IRQFLAGS_H */ > -- > 2.20.1 > >
diff --git a/arch/riscv/include/asm/irqflags.h b/arch/riscv/include/asm/irqflags.h index 6fd8cbfcfcc7..f3aad7bfadb7 100644 --- a/arch/riscv/include/asm/irqflags.h +++ b/arch/riscv/include/asm/irqflags.h @@ -48,7 +48,10 @@ static inline int arch_irqs_disabled(void) /* set interrupt enabled status */ static inline void arch_local_irq_restore(unsigned long flags) { - csr_set(CSR_STATUS, flags & SR_IE); + if (flags & SR_IE) + csr_set(CSR_STATUS, SR_IE); + else + csr_clear(CSR_STATUS, SR_IE); } #endif /* _ASM_RISCV_IRQFLAGS_H */
When arch_local_irq_restore() is called with flags indicating irqs disabled, we need to clear SR_IE bit in CSR_STATUS, whereas current implementation based on csr_set() function only sets SR_IE bit of CSR_STATUS when SR_IE bit of flags is high and does nothing when SR_IE bit of flags is low. This commit supplies csr clear operation when calling irq restore function with flags indicating irq disabled. Fixes: 6d60b6ee0c97 ("RISC-V: Device, timer, IRQs, and the SBI") Signed-off-by: Xu Lu <luxu.kernel@bytedance.com> --- arch/riscv/include/asm/irqflags.h | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)