From 4134b8c8811f23aa8a281db50dcee64dda414736 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Thu, 8 Dec 2011 11:25:50 +0800 Subject: ACPI, APEI, Resolve false conflict between ACPI NVS and APEI Some firmware will access memory in ACPI NVS region via APEI. That is, instructions in APEI ERST/EINJ table will read/write ACPI NVS region. The original resource conflict checking in APEI code will check memory/ioport accessed by APEI via general resource management mech. But ACPI NVS region is marked as busy already, so that the false resource conflict will prevent APEI ERST/EINJ to work. To fix this, this patch excludes ACPI NVS regions when APEI components request resources. So that they will not conflict with ACPI NVS regions. Reported-and-tested-by: Pavel Ivanov Signed-off-by: Huang Ying Signed-off-by: Len Brown --- drivers/acpi/apei/apei-base.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c index f2c5062e2b3..4abb6c74a93 100644 --- a/drivers/acpi/apei/apei-base.c +++ b/drivers/acpi/apei/apei-base.c @@ -449,8 +449,19 @@ int apei_resources_sub(struct apei_resources *resources1, } EXPORT_SYMBOL_GPL(apei_resources_sub); +static int apei_get_nvs_callback(__u64 start, __u64 size, void *data) +{ + struct apei_resources *resources = data; + return apei_res_add(&resources->iomem, start, size); +} + +static int apei_get_nvs_resources(struct apei_resources *resources) +{ + return acpi_nvs_for_each_region(apei_get_nvs_callback, resources); +} + /* - * IO memory/port rersource management mechanism is used to check + * IO memory/port resource management mechanism is used to check * whether memory/port area used by GARs conflicts with normal memory * or IO memory/port of devices. */ @@ -459,12 +470,26 @@ int apei_resources_request(struct apei_resources *resources, { struct apei_res *res, *res_bak = NULL; struct resource *r; + struct apei_resources nvs_resources; int rc; rc = apei_resources_sub(resources, &apei_resources_all); if (rc) return rc; + /* + * Some firmware uses ACPI NVS region, that has been marked as + * busy, so exclude it from APEI resources to avoid false + * conflict. + */ + apei_resources_init(&nvs_resources); + rc = apei_get_nvs_resources(&nvs_resources); + if (rc) + goto res_fini; + rc = apei_resources_sub(resources, &nvs_resources); + if (rc) + goto res_fini; + rc = -EINVAL; list_for_each_entry(res, &resources->iomem, list) { r = request_mem_region(res->start, res->end - res->start, @@ -511,6 +536,8 @@ err_unmap_iomem: break; release_mem_region(res->start, res->end - res->start); } +res_fini: + apei_resources_fini(&nvs_resources); return rc; } EXPORT_SYMBOL_GPL(apei_resources_request); -- cgit v1.2.3