On 22/3/25 22:50, Francesco Lavra wrote:
On 2025-02-18 at 11:09, Alexey Kardashevskiy wrote:
@@ -601,6 +603,25 @@ struct sev_data_snp_addr {
u64 address; /* In/Out */
} __packed;
+/**
+ * struct sev_data_snp_feature_info - SEV_CMD_SNP_FEATURE_INFO
command params
+ *
+ * @len: length of this struct
+ * @ecx_in: subfunction index of CPUID Fn8000_0024
+ * @feature_info_paddr: physical address of a page with
sev_snp_feature_info
+ */
+#define SNP_FEATURE_FN8000_0024_EBX_X00_SEVTIO 1
According to the SNP firmware ABI spec, support for SEV TIO commands is
indicated by bit 1 (bit 0 is for SEV legacy commands).
well, I wanted a bit number (which is 1) but this is wrong nevertheless:
present = (fi.ebx & SNP_FEATURE_FN8000_0024_EBX_X00_SEVTIO) != 0;
should be:
present = (fi.ebx & BIT(SNP_FEATURE_FN8000_0024_EBX_X00_SEVTIO)) != 0;
good spotting!
+static int snp_get_feature_info(struct sev_device *sev, u32 ecx,
struct sev_snp_feature_info *fi)
+{
+ struct sev_user_data_snp_status status = { 0 };
+ int psp_ret = 0, ret;
+
+ ret = snp_platform_status_locked(sev, &status, &psp_ret);
+ if (ret)
+ return ret;
+ if (ret != SEV_RET_SUCCESS)
s/ret/psp_ret/
yeah I noticed this after posting. Thanks,
+ return -EFAULT;
+ if (!status.feature_info)
+ return -ENOENT;
+
+ ret = snp_feature_info_locked(sev, ecx, fi, &psp_ret);
+ if (ret)
+ return ret;
+ if (ret != SEV_RET_SUCCESS)
Same here
--
Alexey
