From 867f9d463b82462793ea4610e748be0b04b37fc7 Mon Sep 17 00:00:00 2001 From: Andy Whitcroft Date: Thu, 19 Jun 2014 11:19:16 +0100 Subject: [PATCH] ACPI / resources: only reject zero length resources based at address zero The recently merged change (in v3.14-rc6) to ACPI resource detection (below) causes all zero length ACPI resources to be elided from the table: commit b355cee88e3b1a193f0e9a81db810f6f83ad728b Author: Zhang Rui Date: Thu Feb 27 11:37:15 2014 +0800 ACPI / resources: ignore invalid ACPI device resources This change has caused a regression in (at least) serial port detection for a number of machines (see LP#1313981 [1]). These seem to represent their IO regions (presumably incorrectly) as a zero length region. Reverting the above commit restores these serial devices. Only elide zero length resources which lie at address 0. Fixes: b355cee88e3b (ACPI / resources: ignore invalid ACPI device resources) Signed-off-by: Andy Whitcroft Acked-by: Zhang Rui Cc: 3.14+ # 3.14+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/resource.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c index 0bdacc5e26a3..2ba8f02ced36 100644 --- a/drivers/acpi/resource.c +++ b/drivers/acpi/resource.c @@ -77,7 +77,7 @@ bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res) switch (ares->type) { case ACPI_RESOURCE_TYPE_MEMORY24: memory24 = &ares->data.memory24; - if (!memory24->address_length) + if (!memory24->minimum && !memory24->address_length) return false; acpi_dev_get_memresource(res, memory24->minimum, memory24->address_length, @@ -85,7 +85,7 @@ bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res) break; case ACPI_RESOURCE_TYPE_MEMORY32: memory32 = &ares->data.memory32; - if (!memory32->address_length) + if (!memory32->minimum && !memory32->address_length) return false; acpi_dev_get_memresource(res, memory32->minimum, memory32->address_length, @@ -93,7 +93,7 @@ bool acpi_dev_resource_memory(struct acpi_resource *ares, struct resource *res) break; case ACPI_RESOURCE_TYPE_FIXED_MEMORY32: fixed_memory32 = &ares->data.fixed_memory32; - if (!fixed_memory32->address_length) + if (!fixed_memory32->address && !fixed_memory32->address_length) return false; acpi_dev_get_memresource(res, fixed_memory32->address, fixed_memory32->address_length, @@ -150,7 +150,7 @@ bool acpi_dev_resource_io(struct acpi_resource *ares, struct resource *res) switch (ares->type) { case ACPI_RESOURCE_TYPE_IO: io = &ares->data.io; - if (!io->address_length) + if (!io->minimum && !io->address_length) return false; acpi_dev_get_ioresource(res, io->minimum, io->address_length, @@ -158,7 +158,7 @@ bool acpi_dev_resource_io(struct acpi_resource *ares, struct resource *res) break; case ACPI_RESOURCE_TYPE_FIXED_IO: fixed_io = &ares->data.fixed_io; - if (!fixed_io->address_length) + if (!fixed_io->address && !fixed_io->address_length) return false; acpi_dev_get_ioresource(res, fixed_io->address, fixed_io->address_length, -- 2.34.1