Re: [PATCH Part1 RFC v4 15/36] x86/mm: Add support to validate memory when changing C-bit

Brijesh Singh
2021-08-17T18:18:54Z

On 8/17/21 1:17 PM, Borislav Petkov wrote:
> On Tue, Aug 17, 2021 at 01:07:40PM -0500, Brijesh Singh wrote:
>>>> + if (!desc)
>>>> + panic("failed to allocate memory");
>>>
>>> Make that error message more distinctive so that *if* it happens, one
>>> can pinpoint the place in the code where the panic comes from.
>>>
>>
>> Now I am running checkpatch and notice that it complain about the message
>> too. I can add a BUG() or WARN() to get the stack trace before the crashing.
>
> checkpatch complains because there's a kmalloc before it and if it
> fails, the mm core will issue a warning so there's no need for a warning
> here.
>
> But in this case, you want to panic and checkpatch doesn't see that so
> you can ignore it here and leave the panic message but make it more
> distinctive so one can find it by grepping. IOW, something like
>
> if (!desc)
> panic("SEV-SNP: Failed to allocame memory for PSC descriptor");
>

Got it, I will update the message accordingly.

thanks