From 46d12f0bcb17b2de89a059114349d472b7eb1783 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Thu, 8 Dec 2011 11:25:45 +0800 Subject: [PATCH] ACPI, APEI, Printk queued error record before panic Because printk is not safe inside NMI handler, the recoverable error records received in NMI handler will be queued to be printked in a delayed IRQ context via irq_work. If a fatal error occurs after the recoverable error and before the irq_work processed, we lost a error report. To solve the issue, the queued error records are printked in NMI handler if system will go panic. Signed-off-by: Huang Ying Signed-off-by: Len Brown --- drivers/acpi/apei/ghes.c | 53 +++++++++++++++++++++++++++++++++------- 1 file changed, 44 insertions(+), 9 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 9dcb2d86aeab..aaf36090de1e 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -740,26 +740,34 @@ static int ghes_notify_sci(struct notifier_block *this, return ret; } +static struct llist_node *llist_nodes_reverse(struct llist_node *llnode) +{ + struct llist_node *next, *tail = NULL; + + while (llnode) { + next = llnode->next; + llnode->next = tail; + tail = llnode; + llnode = next; + } + + return tail; +} + static void ghes_proc_in_irq(struct irq_work *irq_work) { - struct llist_node *llnode, *next, *tail = NULL; + struct llist_node *llnode, *next; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic *generic; struct acpi_hest_generic_status *estatus; u32 len, node_len; + llnode = llist_del_all(&ghes_estatus_llist); /* * Because the time order of estatus in list is reversed, * revert it back to proper order. */ - llnode = llist_del_all(&ghes_estatus_llist); - while (llnode) { - next = llnode->next; - llnode->next = tail; - tail = llnode; - llnode = next; - } - llnode = tail; + llnode = llist_nodes_reverse(llnode); while (llnode) { next = llnode->next; estatus_node = llist_entry(llnode, struct ghes_estatus_node, @@ -779,6 +787,32 @@ static void ghes_proc_in_irq(struct irq_work *irq_work) } } +static void ghes_print_queued_estatus(void) +{ + struct llist_node *llnode; + struct ghes_estatus_node *estatus_node; + struct acpi_hest_generic *generic; + struct acpi_hest_generic_status *estatus; + u32 len, node_len; + + llnode = llist_del_all(&ghes_estatus_llist); + /* + * Because the time order of estatus in list is reversed, + * revert it back to proper order. + */ + llnode = llist_nodes_reverse(llnode); + while (llnode) { + estatus_node = llist_entry(llnode, struct ghes_estatus_node, + llnode); + estatus = GHES_ESTATUS_FROM_NODE(estatus_node); + len = apei_estatus_len(estatus); + node_len = GHES_ESTATUS_NODE_LEN(len); + generic = estatus_node->generic; + ghes_print_estatus(NULL, generic, estatus); + llnode = llnode->next; + } +} + static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) { struct ghes *ghes, *ghes_global = NULL; @@ -804,6 +838,7 @@ static int ghes_notify_nmi(unsigned int cmd, struct pt_regs *regs) if (sev_global >= GHES_SEV_PANIC) { oops_begin(); + ghes_print_queued_estatus(); __ghes_print_estatus(KERN_EMERG, ghes_global->generic, ghes_global->estatus); /* reboot to log the error! */ -- 2.39.5