From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kenji Kaneshige Date: Fri, 01 Jul 2005 09:53:10 +0000 Subject: [patch 2.6.13-rc1] assign_irq_vector() should not panic Message-Id: <42C51286.5020507@jp.fujitsu.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Hi, This is the updated version of the patch I've posted at: http://marc.theaimsgroup.com/?l=linux-ia64&m1803534229544&w=2 Tony, could you consider applying this? Thanks, Kenji Kaneshige Current assign_irq_vector() will panic if interrupt vectors is running out. But I think how to handle the case of lack of interrupt vectors should be handled by the caller of this function. For example, some PCI devices can raise the interrupt signal via both MSI and I/O APIC. So even if the driver for these device fails to allocate a vector for MSI, the driver still has a chance to use I/O APIC based interrupt. But currently there is no chance for these driver to use I/O APIC based interrupt because kernel will panic when assign_irq_vector() fails to allocate interrupt vector. The following patch changes assign_irq_vector() for ia64 to return negative value on error instead of panic. Signed-off-by: Kenji Kaneshige --- linux-2.6.13-rc1-kanesige/arch/ia64/kernel/iosapic.c | 13 +++++++++---- linux-2.6.13-rc1-kanesige/arch/ia64/kernel/irq_ia64.c | 13 +------------ linux-2.6.13-rc1-kanesige/include/asm-ia64/hw_irq.h | 1 - 3 files changed, 10 insertions(+), 17 deletions(-) diff -puN arch/ia64/kernel/iosapic.c~remove-panic-assign_irq_vector-ia64 arch/ia64/kernel/iosapic.c --- linux-2.6.13-rc1/arch/ia64/kernel/iosapic.c~remove-panic-assign_irq_vector-ia64 2005-06-30 15:26:19.000000000 +0900 +++ linux-2.6.13-rc1-kanesige/arch/ia64/kernel/iosapic.c 2005-06-30 15:27:16.000000000 +0900 @@ -489,8 +489,6 @@ static int iosapic_find_sharable_vector } } } - if (vector < 0) - panic("%s: out of interrupt vectors!\n", __FUNCTION__); return vector; } @@ -506,6 +504,8 @@ iosapic_reassign_vector (int vector) if (!list_empty(&iosapic_intr_info[vector].rtes)) { new_vector = assign_irq_vector(AUTO_ASSIGN); + if (new_vector < 0) + panic("%s: out of interrupt vectors!\n", __FUNCTION__); printk(KERN_INFO "Reassigning vector %d to %d\n", vector, new_vector); memcpy(&iosapic_intr_info[new_vector], &iosapic_intr_info[vector], sizeof(struct iosapic_intr_info)); @@ -734,9 +734,12 @@ again: spin_unlock_irqrestore(&iosapic_lock, flags); /* If vector is running out, we try to find a sharable vector */ - vector = assign_irq_vector_nopanic(AUTO_ASSIGN); - if (vector < 0) + vector = assign_irq_vector(AUTO_ASSIGN); + if (vector < 0) { vector = iosapic_find_sharable_vector(trigger, polarity); + if (vector < 0) + panic("%s: out of interrupt vectors!\n", __FUNCTION__); + } spin_lock_irqsave(&irq_descp(vector)->lock, flags); spin_lock(&iosapic_lock); @@ -884,6 +887,8 @@ iosapic_register_platform_intr (u32 int_ break; case ACPI_INTERRUPT_INIT: vector = assign_irq_vector(AUTO_ASSIGN); + if (vector < 0) + panic("%s: out of interrupt vectors!\n", __FUNCTION__); delivery = IOSAPIC_INIT; break; case ACPI_INTERRUPT_CPEI: diff -puN arch/ia64/kernel/irq_ia64.c~remove-panic-assign_irq_vector-ia64 arch/ia64/kernel/irq_ia64.c --- linux-2.6.13-rc1/arch/ia64/kernel/irq_ia64.c~remove-panic-assign_irq_vector-ia64 2005-06-30 15:26:19.000000000 +0900 +++ linux-2.6.13-rc1-kanesige/arch/ia64/kernel/irq_ia64.c 2005-06-30 15:26:19.000000000 +0900 @@ -63,7 +63,7 @@ EXPORT_SYMBOL(isa_irq_to_vector_map); static unsigned long ia64_vector_mask[BITS_TO_LONGS(IA64_NUM_DEVICE_VECTORS)]; int -assign_irq_vector_nopanic (int irq) +assign_irq_vector (int irq) { int pos, vector; again: @@ -76,17 +76,6 @@ assign_irq_vector_nopanic (int irq) return vector; } -int -assign_irq_vector (int irq) -{ - int vector = assign_irq_vector_nopanic(irq); - - if (vector < 0) - panic("assign_irq_vector: out of interrupt vectors!"); - - return vector; -} - void free_irq_vector (int vector) { diff -puN include/asm-ia64/hw_irq.h~remove-panic-assign_irq_vector-ia64 include/asm-ia64/hw_irq.h --- linux-2.6.13-rc1/include/asm-ia64/hw_irq.h~remove-panic-assign_irq_vector-ia64 2005-06-30 15:27:55.000000000 +0900 +++ linux-2.6.13-rc1-kanesige/include/asm-ia64/hw_irq.h 2005-06-30 15:28:15.000000000 +0900 @@ -81,7 +81,6 @@ extern __u8 isa_irq_to_vector_map[16]; extern struct hw_interrupt_type irq_type_ia64_lsapic; /* CPU-internal interrupt controller */ -extern int assign_irq_vector_nopanic (int irq); /* allocate a free vector without panic */ extern int assign_irq_vector (int irq); /* allocate a free vector */ extern void free_irq_vector (int vector); extern void ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect); _