Re: [PATCH v7 7/9] ACPI: APEI: EINJ: Add debugfs files for EINJv2 support

["Luck, Tony" <tony.luck@intel.com>]

On Tue, May 06, 2025 at 02:38:11PM -0700, Zaid Alali wrote:
> Create a debugfs blob file to be used for reading the user
> input for the component array. EINJv2 enables users to inject
> errors to multiple components/devices at the same time using
> component array.
> 
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> Signed-off-by: Zaid Alali <zaidal@os.amperecomputing.com>
> ---
>  drivers/acpi/apei/einj-core.c | 21 ++++++++++++++++++++-
>  1 file changed, 20 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c
> index 60e4f3dc7055..44f9166c3881 100644
> --- a/drivers/acpi/apei/einj-core.c
> +++ b/drivers/acpi/apei/einj-core.c
> @@ -33,6 +33,7 @@
>  #define SLEEP_UNIT_MAX		5000			/* 5ms */
>  /* Firmware should respond within 1 seconds */
>  #define FIRMWARE_TIMEOUT	(1 * USEC_PER_SEC)
> +#define COMP_ARR_SIZE		1024
>  #define ACPI65_EINJV2_SUPP	BIT(30)
>  #define ACPI5_VENDOR_BIT	BIT(31)
>  #define MEM_ERROR_MASK		(ACPI_EINJ_MEMORY_CORRECTABLE | \
> @@ -107,6 +108,8 @@ static struct debugfs_blob_wrapper vendor_blob;
>  static struct debugfs_blob_wrapper vendor_errors;
>  static char vendor_dev[64];
>  
> +static struct debugfs_blob_wrapper einjv2_component_arr;
> +static void *user_input;

Better name for this? "user_input" is too generic.

>  static u32 available_error_type;
>  static u32 available_error_type_v2;
>  
> @@ -689,6 +692,7 @@ static u64 error_param3;
>  static u64 error_param4;
>  static struct dentry *einj_debug_dir;
>  static char einj_buf[32];
> +static bool EINJv2_enabled;
>  static struct { u32 mask; const char *str; } const einj_error_type_string[] = {
>  	{ BIT(0), "Processor Correctable" },
>  	{ BIT(1), "Processor Uncorrectable non-fatal" },
> @@ -718,7 +722,7 @@ static int available_error_type_show(struct seq_file *m, void *v)
>  		if (available_error_type & einj_error_type_string[pos].mask)
>  			seq_printf(m, "0x%08x\t%s\n", einj_error_type_string[pos].mask,
>  				   einj_error_type_string[pos].str);
> -	if (available_error_type & ACPI65_EINJV2_SUPP) {
> +	if ((available_error_type & ACPI65_EINJV2_SUPP) && EINJv2_enabled) {
>  		for (int pos = 0; pos < ARRAY_SIZE(einjv2_error_type_string); pos++) {
>  			if (available_error_type_v2 & einjv2_error_type_string[pos].mask)
>  				seq_printf(m, "V2_0x%08x\t%s\n", einjv2_error_type_string[pos].mask,
> @@ -901,8 +905,22 @@ static int __init einj_probe(struct platform_device *pdev)
>  				   &error_param4);
>  		debugfs_create_x32("notrigger", S_IRUSR | S_IWUSR,
>  				   einj_debug_dir, &notrigger);
> +		if (available_error_type & ACPI65_EINJV2_SUPP) {
> +			user_input = kzalloc(COMP_ARR_SIZE, GFP_KERNEL);
> +			if (!user_input) {
> +				EINJv2_enabled = false;
> +				pr_info("EINJv2 is disabled: not enough memory\n");
> +				goto skip_EINJv2;
> +			}
> +			EINJv2_enabled = true;
> +			einjv2_component_arr.data = user_input;
> +			einjv2_component_arr.size = COMP_ARR_SIZE;
> +			debugfs_create_blob("einjv2_component_array", S_IRUSR | S_IWUSR,
> +					einj_debug_dir, &einjv2_component_arr);
> +		}
>  	}
>  
> +skip_EINJv2:
>  	if (vendor_dev[0]) {
>  		vendor_blob.data = vendor_dev;
>  		vendor_blob.size = strlen(vendor_dev);
> @@ -944,6 +962,7 @@ static void __exit einj_remove(struct platform_device *pdev)
>  		if (vendor_errors.size)
>  			acpi_os_unmap_memory(vendor_errors.data, vendor_errors.size);
>  	}
> +	kfree(user_input);
>  	einj_exec_ctx_init(&ctx);
>  	apei_exec_post_unmap_gars(&ctx);
>  	apei_resources_release(&einj_resources);
> -- 
> 2.43.0
>