2022-01-12 18:28:25

by Rafael J. Wysocki

Subject: [PATCH v1 1/2] ACPI: CPPC: Fix up I/O port access in cpc_read()

From: Rafael J. Wysocki <[email protected]>

The code as currently implemented does not work on big endian systems,
so fix it up.

Fixes: a2c8f92bea5f ("ACPI: CPPC: Implement support for SystemIO registers")
Reported-by: Dan Carpenter <[email protected]>
Suggested-by: Dan Carpenter <[email protected]>
Link: https://lore.kernel.org/linux-acpi/20220111092928.GA24968@kili/
Signed-off-by: Rafael J. Wysocki <[email protected]>
---
drivers/acpi/cppc_acpi.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

Index: linux-pm/drivers/acpi/cppc_acpi.c
===================================================================
--- linux-pm.orig/drivers/acpi/cppc_acpi.c
+++ linux-pm/drivers/acpi/cppc_acpi.c
@@ -929,16 +929,18 @@ static int cpc_read(int cpu, struct cpc_

if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
u32 width = 8 << (reg->access_width - 1);
+ u32 val_u32;
acpi_status status;

status = acpi_os_read_port((acpi_io_address)reg->address,
- (u32 *)val, width);
+ &val_u32, width);
if (ACPI_FAILURE(status)) {
pr_debug("Error: Failed to read SystemIO port %llx\n",
reg->address);
return -EFAULT;
}

+ *val = val_u32;
return 0;
} else if (reg->space_id == ACPI_ADR_SPACE_PLATFORM_COMM && pcc_ss_id >= 0)
vaddr = GET_PCC_VADDR(reg->address, pcc_ss_id);

2022-01-13 03:01:05

by Huang Rui

Subject: Re: [PATCH v1 1/2] ACPI: CPPC: Fix up I/O port access in cpc_read()

On Wed, Jan 12, 2022 at 07:26:32PM +0100, Rafael J. Wysocki wrote:
> From: Rafael J. Wysocki <[email protected]>
>
> The code as currently implemented does not work on big endian systems,
> so fix it up.
>
> Fixes: a2c8f92bea5f ("ACPI: CPPC: Implement support for SystemIO registers")
> Reported-by: Dan Carpenter <[email protected]>
> Suggested-by: Dan Carpenter <[email protected]>
> Link: https://lore.kernel.org/linux-acpi/20220111092928.GA24968@kili/
> Signed-off-by: Rafael J. Wysocki <[email protected]>

Acked-by: Huang Rui <[email protected]>

> ---
> drivers/acpi/cppc_acpi.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> Index: linux-pm/drivers/acpi/cppc_acpi.c
> ===================================================================
> --- linux-pm.orig/drivers/acpi/cppc_acpi.c
> +++ linux-pm/drivers/acpi/cppc_acpi.c
> @@ -929,16 +929,18 @@ static int cpc_read(int cpu, struct cpc_
>
> if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
> u32 width = 8 << (reg->access_width - 1);
> + u32 val_u32;
> acpi_status status;
>
> status = acpi_os_read_port((acpi_io_address)reg->address,
> - (u32 *)val, width);
> + &val_u32, width);
> if (ACPI_FAILURE(status)) {
> pr_debug("Error: Failed to read SystemIO port %llx\n",
> reg->address);
> return -EFAULT;
> }
>
> + *val = val_u32;
> return 0;
> } else if (reg->space_id == ACPI_ADR_SPACE_PLATFORM_COMM && pcc_ss_id >= 0)
> vaddr = GET_PCC_VADDR(reg->address, pcc_ss_id);
>
>
>