Commit 4f44b8f0 authored Apr 14, 2019 by Andy Lutomirski Committed by Borislav Petkov Apr 17, 2019

x86/irq/64: Remove a hardcoded irq_stack_union access



stack_overflow_check() is using both irq_stack_ptr and irq_stack_union
to find the IRQ stack. That's going to break when vmapped irq stacks are
introduced.

Change it to just use irq_stack_ptr.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190414160143.872549191@linutronix.de

parent fa332154

arch/x86/kernel/irq_64.c

+1 −2

Original line number	Diff line number	Diff line
		@@ -55,9 +55,8 @@ static inline void stack_overflow_check(struct pt_regs *regs)
		regs->sp <= curbase + THREAD_SIZE)
		return;

		irq_stack_top = (u64)this_cpu_ptr(irq_stack_union.irq_stack) +
		STACK_TOP_MARGIN;
		irq_stack_bottom = (u64)__this_cpu_read(irq_stack_ptr);
		irq_stack_top = irq_stack_bottom - IRQ_STACK_SIZE + STACK_TOP_MARGIN;
		if (regs->sp >= irq_stack_top && regs->sp <= irq_stack_bottom)
		return;

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