Re: [PATCH 1/3] powerpc/pseries: Correct secvar format representation for static key management
From: Andrew Donnellan <hidden>
Date: 2025-05-07 06:17:41
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On Wed, 2025-05-07 at 00:29 +0530, Srish Srinivasan wrote:
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+ rc = plpks_read_fw_var(&var); + if (rc) { + pr_info("Error %ld reading SB_VERSION from firmware\n", rc);We need to check for -ENOENT, otherwise this message is going to be printed every time you boot a machine in static mode.Yes, I agree with your concern. I just want to add that, as per my understanding, we need to check for both -ENOENT and -EPERM, as explained below: As per H_PKS_READ_OBJECT semantics described in the PAPR v10.60 (https://files.openpower.foundation/s/XFgfMaqLMD5Bcm8), * If the object is not world readable, verify that the consumer password matches the stored value in the hypervisor. Else return H_AUTHORITY. * Verify if the object exists, else return H_NOT_FOUND. * Verify if the policy for the object is met, else return H_AUTHORITY. So, the hypervisor returns H_NOT_FOUND only for the authenticated consumer. For unauthenticated consumers, which is the case here, it would return H_AUTHORITY.
We expect SB_VERSION to always be world-readable, I think? In which case it shouldn't return H_AUTHORITY / -EPERM, ever, and if it does that's an error which should be handled as an error. Or am I misinterpreting the spec here? -- Andrew Donnellan OzLabs, ADL Canberra ajd@linux.ibm.com IBM Australia Limited