From 76e6faf7a3a3ad3e18a1b70f9e4cd96cdf58140d Mon Sep 17 00:00:00 2001 From: Linas Vepstas Date: Thu, 3 Nov 2005 18:49:15 -0600 Subject: [PATCH] [PATCH] ppc64: avoid PCI error reporting for empty slots 06-eeh-empty-slot-error.patch Performing PCI config-space reads to empty PCI slots can lead to reports of "permanent failure" from the firmware. Ignore permanent failures on empty slots. Signed-off-by: Linas Vepstas Signed-off-by: Paul Mackerras --- arch/ppc64/kernel/eeh.c | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/arch/ppc64/kernel/eeh.c b/arch/ppc64/kernel/eeh.c index b231594..0060934 100644 --- a/arch/ppc64/kernel/eeh.c +++ b/arch/ppc64/kernel/eeh.c @@ -617,7 +617,32 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) * In any case they must share a common PHB. */ ret = read_slot_reset_state(pdn, rets); - if (!(ret == 0 && rets[1] == 1 && (rets[0] == 2 || rets[0] == 4))) { + + /* If the call to firmware failed, punt */ + if (ret != 0) { + printk(KERN_WARNING "EEH: read_slot_reset_state() failed; rc=%d dn=%s\n", + ret, dn->full_name); + __get_cpu_var(false_positives)++; + return 0; + } + + /* If EEH is not supported on this device, punt. */ + if (rets[1] != 1) { + printk(KERN_WARNING "EEH: event on unsupported device, rc=%d dn=%s\n", + ret, dn->full_name); + __get_cpu_var(false_positives)++; + return 0; + } + + /* If not the kind of error we know about, punt. */ + if (rets[0] != 2 && rets[0] != 4 && rets[0] != 5) { + __get_cpu_var(false_positives)++; + return 0; + } + + /* Note that config-io to empty slots may fail; + * we recognize empty because they don't have children. */ + if ((rets[0] == 5) && (dn->child == NULL)) { __get_cpu_var(false_positives)++; return 0; } @@ -650,7 +675,7 @@ int eeh_dn_check_failure(struct device_node *dn, struct pci_dev *dev) /* Most EEH events are due to device driver bugs. Having * a stack trace will help the device-driver authors figure * out what happened. So print that out. */ - dump_stack(); + if (rets[0] != 5) dump_stack(); schedule_work(&eeh_event_wq); return 0; -- 2.7.4