From: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> io_apic_redir_entries has a huge conceptual bug. It returns the maximum redirection entry not the number of redirection entries. Which simply does not match what the name of the function. This just caught me and it caught Feng Tang, and Len Brown when they wrote sfi_parse_ioapic. Modify io_apic_redir_entries to actually return the number of redirection entries, and fix the callers so that they properly handle receiving the number of the number of redirection table entries, instead of the number of redirection table entries less one. While the usage in sfi.c does not show up in this patch it is fixed by virtue of the fact that io_apic_redir_entries now has the semantics sfi_parse_ioapic most reasonably expects. Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> --- arch/x86/kernel/apic/io_apic.c | 10 +++++++--- 1 files changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 54ba1f7..7e139bb 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -3846,7 +3846,11 @@ int __init io_apic_get_redir_entries (int ioapic) reg_01.raw = io_apic_read(ioapic, 1); raw_spin_unlock_irqrestore(&ioapic_lock, flags); - return reg_01.bits.entries; + /* The register returns the maximum index redir index + * supported, which is one less than the total number of redir + * entries. + */ + return reg_01.bits.entries + 1; } void __init probe_nr_irqs_gsi(void) @@ -3862,7 +3866,7 @@ void __init probe_nr_irqs_gsi(void) nr = 0; for (idx = 0; idx < nr_ioapics; idx++) - nr += io_apic_get_redir_entries(idx) + 1; + nr += io_apic_get_redir_entries(idx); if (nr > nr_irqs_gsi) nr_irqs_gsi = nr; @@ -4297,7 +4301,7 @@ void __init mp_register_ioapic(int id, u32 address, u32 gsi_base) */ mp_gsi_routing[idx].gsi_base = gsi_base; mp_gsi_routing[idx].gsi_end = gsi_base + - io_apic_get_redir_entries(idx); + io_apic_get_redir_entries(idx) - 1; printk(KERN_INFO "IOAPIC[%d]: apic_id %d, version %d, address 0x%x, " "GSI %d-%d\n", idx, mp_ioapics[idx].apicid, -- 1.6.5.2.143.g8cc62 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
