A few more

interrupts/interrupts-10.md

@@ -398,7 +398,7 @@ static inline void generic_handle_irq_desc(unsigned int irq, struct irq_desc *de
 }
 ```
 
-But stop... What is it `handle_irq` and why do we call our interrupt handler from the interrupt descriptor when we know that `irqaction` points to the actual interrupt handler? Actually the `irq_desc->handle_irq` is a high level API for the calling interrupt handler routine. It setups during initialization of the [device tree](https://en.wikipedia.org/wiki/Device_tree) and [APIC](https://en.wikipedia.org/wiki/Advanced_Programmable_Interrupt_Controller) initialization. The kernel selects correct function and call chain of the `irq->action(s)` there. In this way, the `serial21285_tx_chars` or the `serial21285_rx_chars` function will be executed after an interrupt will occur.
+But stop... What is it `handle_irq` and why do we call our interrupt handler from the interrupt descriptor when we know that `irqaction` points to the actual interrupt handler? Actually the `irq_desc->handle_irq` is a high-level API for the calling interrupt handler routine. It setups during initialization of the [device tree](https://en.wikipedia.org/wiki/Device_tree) and [APIC](https://en.wikipedia.org/wiki/Advanced_Programmable_Interrupt_Controller) initialization. The kernel selects correct function and call chain of the `irq->action(s)` there. In this way, the `serial21285_tx_chars` or the `serial21285_rx_chars` function will be executed after an interrupt will occur.
 
 In the end of the `do_IRQ` function we call the `irq_exit` function that will exit from the interrupt context, the `set_irq_regs` with the old userspace registers and return:
 
@@ -408,12 +408,12 @@ set_irq_regs(old_regs);
 return 1;
 ```
 
-We already knwo that when an `IRQ` finishes its work, deferred interrupts will be executed if they exist.
+We already know that when an `IRQ` finishes its work, deferred interrupts will be executed if they exist.
 
 Exit from interrupt
 --------------------------------------------------------------------------------
 
-Ok, the interrupt handler finsihed its execution and now we must return from the interrupt. When the work of the `do_IRQ` function will be finsihed, we will return back to the assembler code in the [arch/x86/entry/entry_64.S](https://github.com/torvalds/linux/blob/master/arch/x86/entry_entry_64.S) to the `ret_from_intr` label. First of all we disable interrupts with the `DISABLE_INTERRUPTS` macro that expands to the `cli` instruction and decrement value of the `irq_count` [per-cpu](http://0xax.gitbooks.io/linux-insides/content/Concepts/per-cpu.html) variable. Remember, this variable had value - `1`, when we was in interrupt context:
+Ok, the interrupt handler finished its execution and now we must return from the interrupt. When the work of the `do_IRQ` function will be finsihed, we will return back to the assembler code in the [arch/x86/entry/entry_64.S](https://github.com/torvalds/linux/blob/master/arch/x86/entry_entry_64.S) to the `ret_from_intr` label. First of all we disable interrupts with the `DISABLE_INTERRUPTS` macro that expands to the `cli` instruction and decrement value of the `irq_count` [per-cpu](http://0xax.gitbooks.io/linux-insides/content/Concepts/per-cpu.html) variable. Remember, this variable had value - `1`, when we were in interrupt context:
 
 ```assembly
 DISABLE_INTERRUPTS(CLBR_NONE)