RE: [PATCH v6 08/10] tools/testing/cxl: Use injected poison for get poison list

[Dan Williams <dan.j.williams@intel.com>]

alison.schofield@ wrote:
> From: Alison Schofield <alison.schofield@intel.com>
> 
> Prior to poison inject support, the mock of 'Get Poison List'
> returned a poison list containing a single mocked error record.
> 
> Following the addition of poison inject and clear support to the
> mock driver, use the mock_poison_list[], rather than faking an
> error record. Mock_poison_list[] list tracks the actual poison
> inject and clear requests issued by userspace.
> 
> Signed-off-by: Alison Schofield <alison.schofield@intel.com>
> Reviewed-by: Dave Jiang <dave.jiang@intel.com>
> ---
>  tools/testing/cxl/test/mem.c | 59 ++++++++++++++++++++++++------------
>  1 file changed, 40 insertions(+), 19 deletions(-)
> 
> diff --git a/tools/testing/cxl/test/mem.c b/tools/testing/cxl/test/mem.c
> index 3c3909d30d03..cce7ec8f0efb 100644
> --- a/tools/testing/cxl/test/mem.c
> +++ b/tools/testing/cxl/test/mem.c
> @@ -912,31 +912,52 @@ static struct mock_poison {
>  	u64 dpa;
>  } mock_poison_list[MOCK_INJECT_TEST_MAX];
>  
> +static struct cxl_mbox_poison_out
> +*cxl_get_injected_po(struct cxl_dev_state *cxlds, u64 offset, u64 length)
> +{
> +	struct cxl_mbox_poison_out *po;
> +	int nr_records = 0;
> +	u64 dpa;
> +
> +	po = kzalloc(struct_size(po, record, MOCK_INJECT_DEV_MAX), GFP_KERNEL);
> +	if (!po)
> +		return NULL;

I do not see where this is freed.

> +
> +	for (int i = 0; i < MOCK_INJECT_TEST_MAX; i++) {
> +		if (mock_poison_list[i].cxlds != cxlds)
> +			continue;
> +		if (mock_poison_list[i].dpa < offset ||
> +		    mock_poison_list[i].dpa > offset + length - 1)
> +			continue;
> +
> +		dpa = mock_poison_list[i].dpa + CXL_POISON_SOURCE_INJECTED;
> +		po->record[nr_records].address = cpu_to_le64(dpa);
> +		po->record[nr_records].length = cpu_to_le32(1);
> +		nr_records++;
> +		if (nr_records == MOCK_INJECT_DEV_MAX)
> +			break;
> +	}
> +
> +	/* Always return count, even when zero */
> +	po->count = cpu_to_le16(nr_records);
> +
> +	return po;
> +}
> +
>  static int mock_get_poison(struct cxl_dev_state *cxlds,
>  			   struct cxl_mbox_cmd *cmd)
>  {
>  	struct cxl_mbox_poison_in *pi = cmd->payload_in;
> +	struct cxl_mbox_poison_out *po;
> +	u64 offset = le64_to_cpu(pi->offset);
> +	u64 length = le64_to_cpu(pi->length);
> +	int nr_records;
>  
> -	/* Mock one poison record at pi.offset for 64 bytes */
> -	struct {
> -		struct cxl_mbox_poison_out po;
> -		struct cxl_poison_record record;
> -	} __packed mock_plist = {
> -		.po = {
> -			.count = cpu_to_le16(1),
> -		},
> -		.record = {
> -			.length = cpu_to_le32(1),
> -			.address = cpu_to_le64(le64_to_cpu(pi->offset) +
> -					       CXL_POISON_SOURCE_INJECTED),
> -		},
> -	};
> +	po = cxl_get_injected_po(cxlds, offset, length);
> +	nr_records = le16_to_cpu(po->count);

This needs to check for NULL @po before use.

> +	memcpy(cmd->payload_out, po, struct_size(po, record, nr_records));
> +	cmd->size_out = struct_size(po, record, nr_records);

Looks like the kfree wants to be here. I was going to say just make @po
a static allocation, but I see that you make this dynamically sized in a
later patch. I can fix this up on applying.