From b6c96c0214138186f495e3ee73737c6fc5e4efa2 Mon Sep 17 00:00:00 2001 From: Stratos Psomadakis Date: Thu, 12 Jan 2012 15:44:47 +1030 Subject: lguest: Make sure interrupt is allocated ok by lguest_setup_irq Make sure the interrupt is allocated correctly by lguest_setup_irq (check the return value of irq_alloc_desc_at for -ENOMEM) Signed-off-by: Stratos Psomadakis Signed-off-by: Rusty Russell (cleanups and commentry) --- arch/x86/lguest/boot.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'arch') diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c index cf4603ba866f..642d8805bc1b 100644 --- a/arch/x86/lguest/boot.c +++ b/arch/x86/lguest/boot.c @@ -856,18 +856,23 @@ static void __init lguest_init_IRQ(void) } /* - * With CONFIG_SPARSE_IRQ, interrupt descriptors are allocated as-needed, so - * rather than set them in lguest_init_IRQ we are called here every time an - * lguest device needs an interrupt. - * - * FIXME: irq_alloc_desc_at() can fail due to lack of memory, we should - * pass that up! + * Interrupt descriptors are allocated as-needed, but low-numbered ones are + * reserved by the generic x86 code. So we ignore irq_alloc_desc_at if it + * tells us the irq is already used: other errors (ie. ENOMEM) we take + * seriously. */ -void lguest_setup_irq(unsigned int irq) +int lguest_setup_irq(unsigned int irq) { - irq_alloc_desc_at(irq, 0); + int err; + + /* Returns -ve error or vector number. */ + err = irq_alloc_desc_at(irq, 0); + if (err < 0 && err != -EEXIST) + return err; + irq_set_chip_and_handler_name(irq, &lguest_irq_controller, handle_level_irq, "level"); + return 0; } /* -- cgit v1.2.3-58-ga151