Re: [PATCH] crypto: ccp: Properly unregister /dev/sev on sev PLATFORM_STATUS failure

[Tom Lendacky]

On 8/15/24 07:25, Pavan Kumar Paluri wrote:
> In case of sev PLATFORM_STATUS failure, sev_get_api_version() fails
> resulting in sev_data field of psp_master nulled out. This later becomes
> a problem when unloading the ccp module because the device has not been
> unregistered (via misc_deregister()) before clearing the sev_data field
> of psp_master. As a result, on reloading the ccp module, a duplicate
> device issue is encountered as can be seen from the dmesg log below.
> 
> on reloading ccp module via modprobe ccp
> 

...

> 
> Address this issue by unregistering the /dev/sev before clearing out
> sev_data in case of PLATFORM_STATUS failure.
> 
> Fixes: 200664d5237f ("crypto: ccp: Add Secure Encrypted Virtualization (SEV) command support")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Pavan Kumar Paluri <papaluri@xxxxxxx>

Acked-by: Tom Lendacky <thomas.lendacky@xxxxxxx>

> ---