[PATCH V5 1/2] ACPI / EC: Fix broken 64bit big-endian users of 'global_lock'

From: Viresh Kumar
Date: Sat Sep 26 2015 - 18:04:50 EST


global_lock is defined as an unsigned long and accessing only its lower
32 bits from sysfs is incorrect, as we need to consider other 32 bits
for big endian 64-bit systems. There are no such platforms yet, but the
code needs to be robust for such a case.

Fix that by changing type of 'global_lock' to u32.

Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
BCC'd a lot of people (rather than cc'ing them) to make sure
- the series reaches them
- mailing lists do not block the patchset due to long cc list
- and we don't spam the BCC'd people for every reply

V4->V5:
- Switch back to the original solution of making global_lock u32.
---
drivers/acpi/ec_sys.c | 2 +-
drivers/acpi/internal.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c
index b4c216bab22b..bea8e425a8de 100644
--- a/drivers/acpi/ec_sys.c
+++ b/drivers/acpi/ec_sys.c
@@ -128,7 +128,7 @@ static int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe))
goto error;
if (!debugfs_create_bool("use_global_lock", 0444, dev_dir,
- (u32 *)&first_ec->global_lock))
+ &first_ec->global_lock))
goto error;

if (write_support)
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 9e426210c2a8..9db196de003c 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -138,7 +138,7 @@ struct acpi_ec {
unsigned long gpe;
unsigned long command_addr;
unsigned long data_addr;
- unsigned long global_lock;
+ u32 global_lock;
unsigned long flags;
unsigned long reference_count;
struct mutex mutex;
--
2.4.0

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