From 7d97277b754d3ee098a5ec69b6aaafb00c94e2f2 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 7 Feb 2009 15:39:41 -0800 Subject: acpi/x86: introduce __apci_map_table, v4 to prevent wrongly overwriting fixmap that still want to use. ACPI used to rely on low mappings being all linearly mapped and grew a habit: it never really unmapped certain kinds of tables after use. This can cause problems - for example the hypothetical case when some spurious access still references it. v2: remove prev_map and prev_size in __apci_map_table v3: let acpi_os_unmap_memory() call early_iounmap too, so remove extral calling to early_acpi_os_unmap_memory v4: fix typo in one acpi_get_table_with_size calling Signed-off-by: Yinghai Lu Acked-by: Len Brown Signed-off-by: Ingo Molnar --- drivers/acpi/tables.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'drivers/acpi/tables.c') diff --git a/drivers/acpi/tables.c b/drivers/acpi/tables.c index a8852952fac4..fec1ae36d431 100644 --- a/drivers/acpi/tables.c +++ b/drivers/acpi/tables.c @@ -181,14 +181,15 @@ acpi_table_parse_entries(char *id, struct acpi_subtable_header *entry; unsigned int count = 0; unsigned long table_end; + acpi_size tbl_size; if (!handler) return -EINVAL; if (strncmp(id, ACPI_SIG_MADT, 4) == 0) - acpi_get_table(id, acpi_apic_instance, &table_header); + acpi_get_table_with_size(id, acpi_apic_instance, &table_header, &tbl_size); else - acpi_get_table(id, 0, &table_header); + acpi_get_table_with_size(id, 0, &table_header, &tbl_size); if (!table_header) { printk(KERN_WARNING PREFIX "%4.4s not present\n", id); @@ -206,8 +207,10 @@ acpi_table_parse_entries(char *id, table_end) { if (entry->type == entry_id && (!max_entries || count++ < max_entries)) - if (handler(entry, table_end)) + if (handler(entry, table_end)) { + early_acpi_os_unmap_memory((char *)table_header, tbl_size); return -EINVAL; + } entry = (struct acpi_subtable_header *) ((unsigned long)entry + entry->length); @@ -217,6 +220,7 @@ acpi_table_parse_entries(char *id, "%i found\n", id, entry_id, count - max_entries, count); } + early_acpi_os_unmap_memory((char *)table_header, tbl_size); return count; } @@ -241,17 +245,19 @@ acpi_table_parse_madt(enum acpi_madt_type id, int __init acpi_table_parse(char *id, acpi_table_handler handler) { struct acpi_table_header *table = NULL; + acpi_size tbl_size; if (!handler) return -EINVAL; if (strncmp(id, ACPI_SIG_MADT, 4) == 0) - acpi_get_table(id, acpi_apic_instance, &table); + acpi_get_table_with_size(id, acpi_apic_instance, &table, &tbl_size); else - acpi_get_table(id, 0, &table); + acpi_get_table_with_size(id, 0, &table, &tbl_size); if (table) { handler(table); + early_acpi_os_unmap_memory(table, tbl_size); return 0; } else return 1; @@ -265,8 +271,9 @@ int __init acpi_table_parse(char *id, acpi_table_handler handler) static void __init check_multiple_madt(void) { struct acpi_table_header *table = NULL; + acpi_size tbl_size; - acpi_get_table(ACPI_SIG_MADT, 2, &table); + acpi_get_table_with_size(ACPI_SIG_MADT, 2, &table, &tbl_size); if (table) { printk(KERN_WARNING PREFIX "BIOS bug: multiple APIC/MADT found," @@ -275,6 +282,7 @@ static void __init check_multiple_madt(void) "If \"acpi_apic_instance=%d\" works better, " "notify linux-acpi@vger.kernel.org\n", acpi_apic_instance ? 0 : 2); + early_acpi_os_unmap_memory(table, tbl_size); } else acpi_apic_instance = 0; -- cgit v1.2.3