From: Yinghai Lu Subject: x2apic, dmar: fix using early fixmap mapping for DMAR table parsing Very early detection of the DMAR tables will setup fixmap mapping. For parsing these tables later (while enabling dma and/or interrupt remapping), early fixmap mapping shouldn't be used. Fix it by calling table detection routines again, which will call generic apci_get_table() for setting up the correct mapping. Signed-off-by: Yinghai Lu Signed-off-by: Suresh Siddha --- Index: tip/drivers/pci/dmar.c =================================================================== --- tip.orig/drivers/pci/dmar.c 2008-09-02 16:04:04.000000000 -0700 +++ tip/drivers/pci/dmar.c 2008-09-02 16:41:31.000000000 -0700 @@ -289,6 +289,24 @@ } } +/** + * dmar_table_detect - checks to see if the platform supports DMAR devices + */ +static int __init dmar_table_detect(void) +{ + acpi_status status = AE_OK; + + /* if we could find DMAR table, then there are DMAR devices */ + status = acpi_get_table(ACPI_SIG_DMAR, 0, + (struct acpi_table_header **)&dmar_tbl); + + if (ACPI_SUCCESS(status) && !dmar_tbl) { + printk (KERN_WARNING PREFIX "Unable to map DMAR\n"); + status = AE_NOT_FOUND; + } + + return (ACPI_SUCCESS(status) ? 1 : 0); +} /** * parse_dmar_table - parses the DMA reporting table @@ -300,6 +318,12 @@ struct acpi_dmar_header *entry_header; int ret = 0; + /* + * Do it again, earlier dmar_tbl mapping could be mapped with + * fixed map. + */ + dmar_table_detect(); + dmar = (struct acpi_table_dmar *)dmar_tbl; if (!dmar) return -ENODEV; @@ -430,30 +454,11 @@ return 0; } -/** - * early_dmar_detect - checks to see if the platform supports DMAR devices - */ -int __init early_dmar_detect(void) -{ - acpi_status status = AE_OK; - - /* if we could find DMAR table, then there are DMAR devices */ - status = acpi_get_table(ACPI_SIG_DMAR, 0, - (struct acpi_table_header **)&dmar_tbl); - - if (ACPI_SUCCESS(status) && !dmar_tbl) { - printk (KERN_WARNING PREFIX "Unable to map DMAR\n"); - status = AE_NOT_FOUND; - } - - return (ACPI_SUCCESS(status) ? 1 : 0); -} - void __init detect_intel_iommu(void) { int ret; - ret = early_dmar_detect(); + ret = dmar_table_detect(); #ifdef CONFIG_DMAR { @@ -479,14 +484,16 @@ " x2apic support\n"); dmar_disabled = 1; - return; + goto end; } if (ret && !no_iommu && !iommu_detected && !swiotlb && !dmar_disabled) iommu_detected = 1; } +end: #endif + dmar_tbl = NULL; } Index: tip/include/linux/dmar.h =================================================================== --- tip.orig/include/linux/dmar.h 2008-09-02 16:04:04.000000000 -0700 +++ tip/include/linux/dmar.h 2008-09-02 16:40:40.000000000 -0700 @@ -45,7 +45,6 @@ list_for_each_entry(drhd, &dmar_drhd_units, list) extern int dmar_table_init(void); -extern int early_dmar_detect(void); extern int dmar_dev_scope_init(void); /* Intel IOMMU detection */ -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/