Since commit 488dac0c9237 ("libfs: fix error cast of negative value in
simple_attr_write()"), the EINJ debugfs interface no longer accepts
negative values as input. Attempt to do so will result in EINVAL.

Signed-off-by: Qifu Zhang <zhangqifu@bytedance.com>
---
 Documentation/firmware-guide/acpi/apei/einj.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/firmware-guide/acpi/apei/einj.rst b/Documentation/firmware-guide/acpi/apei/einj.rst
index 55e2331a6438..d6b61d22f525 100644
--- a/Documentation/firmware-guide/acpi/apei/einj.rst
+++ b/Documentation/firmware-guide/acpi/apei/einj.rst
@@ -168,7 +168,7 @@ An error injection example::
   0x00000008	Memory Correctable
   0x00000010	Memory Uncorrectable non-fatal
   # echo 0x12345000 > param1		# Set memory address for injection
-  # echo $((-1 << 12)) > param2		# Mask 0xfffffffffffff000 - anywhere in this page
+  # echo 0xfffffffffffff000 > param2		# Mask - anywhere in this page
   # echo 0x8 > error_type			# Choose correctable memory error
   # echo 1 > error_inject			# Inject now
 
-- 
2.20.1

On Tue, Jul 19, 2022 at 07:50:13PM +0800, Qifu Zhang wrote:
> Since commit 488dac0c9237 ("libfs: fix error cast of negative value in
> simple_attr_write()"), the EINJ debugfs interface no longer accepts
> negative values as input. Attempt to do so will result in EINVAL.
> 
> Signed-off-by: Qifu Zhang <zhangqifu@bytedance.com>

Reviewed-by: Tony Luck <tony.luck@intel.com>

> ---
>  Documentation/firmware-guide/acpi/apei/einj.rst | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Documentation/firmware-guide/acpi/apei/einj.rst b/Documentation/firmware-guide/acpi/apei/einj.rst
> index 55e2331a6438..d6b61d22f525 100644
> --- a/Documentation/firmware-guide/acpi/apei/einj.rst
> +++ b/Documentation/firmware-guide/acpi/apei/einj.rst
> @@ -168,7 +168,7 @@ An error injection example::
>    0x00000008	Memory Correctable
>    0x00000010	Memory Uncorrectable non-fatal
>    # echo 0x12345000 > param1		# Set memory address for injection
> -  # echo $((-1 << 12)) > param2		# Mask 0xfffffffffffff000 - anywhere in this page
> +  # echo 0xfffffffffffff000 > param2		# Mask - anywhere in this page
>    # echo 0x8 > error_type			# Choose correctable memory error
>    # echo 1 > error_inject			# Inject now
>  
> -- 
> 2.20.1
>

On Tue, Jul 19, 2022 at 7:13 PM Luck, Tony <tony.luck@intel.com> wrote:
>
> On Tue, Jul 19, 2022 at 07:50:13PM +0800, Qifu Zhang wrote:
> > Since commit 488dac0c9237 ("libfs: fix error cast of negative value in
> > simple_attr_write()"), the EINJ debugfs interface no longer accepts
> > negative values as input. Attempt to do so will result in EINVAL.
> >
> > Signed-off-by: Qifu Zhang <zhangqifu@bytedance.com>
>
> Reviewed-by: Tony Luck <tony.luck@intel.com>

Applied as 5.20 material, thanks!