The following commit has been merged into the x86/entry branch of tip: Commit-ID: 4c74d51dab3dd655062a4740af150c1835e19cff Gitweb: https://git.kernel.org/tip/4c74d51dab3dd655062a4740af150c1835e19cff Author: Vitaly Kuznetsov <vkuzn...@redhat.com> AuthorDate: Tue, 28 Apr 2020 11:38:23 +02:00 Committer: Thomas Gleixner <t...@linutronix.de> CommitterDate: Wed, 13 May 2020 21:13:54 +02:00
x86/idt: Annotate alloc_intr_gate() with __init There seems to be no reason to allocate interrupt gates after init. Mark alloc_intr_gate() as __init and add WARN_ON() checks making sure it is only used before idt_setup_apic_and_irq_gates() finalizes IDT setup and maps all un-allocated entries to spurious entries. Suggested-by: Thomas Gleixner <t...@linutronix.de> Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Link: https://lkml.kernel.org/r/20200428093824.1451532-3-vkuzn...@redhat.com --- arch/x86/kernel/idt.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 98bcb50..0e92051 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -51,6 +51,9 @@ struct idt_data { #define TSKG(_vector, _gdt) \ G(_vector, NULL, DEFAULT_STACK, GATE_TASK, DPL0, _gdt << 3) + +static bool idt_setup_done __initdata; + /* * Early traps running on the DEFAULT_STACK because the other interrupt * stacks work only after cpu_init(). @@ -323,6 +326,7 @@ void __init idt_setup_apic_and_irq_gates(void) set_intr_gate(i, entry); } #endif + idt_setup_done = true; } /** @@ -352,6 +356,7 @@ void idt_invalidate(void *addr) load_idt(&idt); } +/* This goes away once ASYNC_PF is sanitized */ void __init update_intr_gate(unsigned int n, const void *addr) { if (WARN_ON_ONCE(!test_bit(n, system_vectors))) @@ -359,9 +364,14 @@ void __init update_intr_gate(unsigned int n, const void *addr) set_intr_gate(n, addr); } -void alloc_intr_gate(unsigned int n, const void *addr) +void __init alloc_intr_gate(unsigned int n, const void *addr) { - BUG_ON(n < FIRST_SYSTEM_VECTOR); - if (!test_and_set_bit(n, system_vectors)) + if (WARN_ON(n < FIRST_SYSTEM_VECTOR)) + return; + + if (WARN_ON(idt_setup_done)) + return; + + if (!WARN_ON(test_and_set_bit(n, system_vectors))) set_intr_gate(n, addr); }
