From 0e17b560985afb5190e859d5d4609237a91bb732 Mon Sep 17 00:00:00 2001 From: John Keller Date: Wed, 2 May 2007 09:09:18 -0500 Subject: [PATCH] [IA64] - Altix: hotplug after intr redirect can crash system When redirecting a device interrupt on SN, not all links between platform specific structures are being updated. This can result in a system crash if an interrupt redirection is followed by an unplug of that device. The complete fix also requires a prom update. Though, this patch is backward compatable and not dependent on the prom patch. Signed-off-by: John Keller Signed-off-by: Tony Luck --- arch/ia64/sn/kernel/irq.c | 58 ++++++++++++++++++++++++++---------- include/asm-ia64/sn/sn_sal.h | 1 + 2 files changed, 44 insertions(+), 15 deletions(-) diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c index 8d2a1bfbfe7c..7f6d2360a262 100644 --- a/arch/ia64/sn/kernel/irq.c +++ b/arch/ia64/sn/kernel/irq.c @@ -59,6 +59,22 @@ void sn_intr_free(nasid_t local_nasid, int local_widget, (u64) sn_irq_info->irq_cookie, 0, 0); } +u64 sn_intr_redirect(nasid_t local_nasid, int local_widget, + struct sn_irq_info *sn_irq_info, + nasid_t req_nasid, int req_slice) +{ + struct ia64_sal_retval ret_stuff; + ret_stuff.status = 0; + ret_stuff.v0 = 0; + + SAL_CALL_NOLOCK(ret_stuff, (u64) SN_SAL_IOIF_INTERRUPT, + (u64) SAL_INTR_REDIRECT, (u64) local_nasid, + (u64) local_widget, __pa(sn_irq_info), + (u64) req_nasid, (u64) req_slice, 0); + + return ret_stuff.status; +} + static unsigned int sn_startup_irq(unsigned int irq) { return 0; @@ -127,15 +143,8 @@ struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info, struct sn_irq_info *new_irq_info; struct sn_pcibus_provider *pci_provider; - new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC); - if (new_irq_info == NULL) - return NULL; - - memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info)); - - bridge = (u64) new_irq_info->irq_bridge; + bridge = (u64) sn_irq_info->irq_bridge; if (!bridge) { - kfree(new_irq_info); return NULL; /* irq is not a device interrupt */ } @@ -145,8 +154,25 @@ struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info, local_widget = TIO_SWIN_WIDGETNUM(bridge); else local_widget = SWIN_WIDGETNUM(bridge); - vector = sn_irq_info->irq_irq; + + /* Make use of SAL_INTR_REDIRECT if PROM supports it */ + status = sn_intr_redirect(local_nasid, local_widget, sn_irq_info, nasid, slice); + if (!status) { + new_irq_info = sn_irq_info; + goto finish_up; + } + + /* + * PROM does not support SAL_INTR_REDIRECT, or it failed. + * Revert to old method. + */ + new_irq_info = kmalloc(sizeof(struct sn_irq_info), GFP_ATOMIC); + if (new_irq_info == NULL) + return NULL; + + memcpy(new_irq_info, sn_irq_info, sizeof(struct sn_irq_info)); + /* Free the old PROM new_irq_info structure */ sn_intr_free(local_nasid, local_widget, new_irq_info); unregister_intr_pda(new_irq_info); @@ -162,11 +188,18 @@ struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info, return NULL; } + register_intr_pda(new_irq_info); + spin_lock(&sn_irq_info_lock); + list_replace_rcu(&sn_irq_info->list, &new_irq_info->list); + spin_unlock(&sn_irq_info_lock); + call_rcu(&sn_irq_info->rcu, sn_irq_info_free); + + +finish_up: /* Update kernels new_irq_info with new target info */ cpuid = nasid_slice_to_cpuid(new_irq_info->irq_nasid, new_irq_info->irq_slice); new_irq_info->irq_cpuid = cpuid; - register_intr_pda(new_irq_info); pci_provider = sn_pci_provider[new_irq_info->irq_bridge_type]; @@ -178,11 +211,6 @@ struct sn_irq_info *sn_retarget_vector(struct sn_irq_info *sn_irq_info, pci_provider && pci_provider->target_interrupt) (pci_provider->target_interrupt)(new_irq_info); - spin_lock(&sn_irq_info_lock); - list_replace_rcu(&sn_irq_info->list, &new_irq_info->list); - spin_unlock(&sn_irq_info_lock); - call_rcu(&sn_irq_info->rcu, sn_irq_info_free); - #ifdef CONFIG_SMP cpuphys = cpu_physical_id(cpuid); set_irq_affinity_info((vector & 0xff), cpuphys, 0); diff --git a/include/asm-ia64/sn/sn_sal.h b/include/asm-ia64/sn/sn_sal.h index 2c4004eb5a68..291e8ceed6e6 100644 --- a/include/asm-ia64/sn/sn_sal.h +++ b/include/asm-ia64/sn/sn_sal.h @@ -106,6 +106,7 @@ /* interrupt handling */ #define SAL_INTR_ALLOC 1 #define SAL_INTR_FREE 2 +#define SAL_INTR_REDIRECT 3 /* * operations available on the generic SN_SAL_SYSCTL_OP -- 2.20.1