On Mon, Dec 16, 2024 at 3:58 PM Ashish Kalra <Ashish.Kalra@xxxxxxx> wrote:
>
> From: Ashish Kalra <ashish.kalra@xxxxxxx>
>
> Register the SNP panic notifier if and only if SNP is actually
> initialized and deregistering the notifier when shutting down
> SNP in PSP driver when KVM module is unloaded.
>
> Currently the SNP panic notifier is being registered
> irrespective of SNP being enabled/initialized and with this
> change the SNP panic notifier is registered only if SNP
> support is enabled and initialized.
>
> Signed-off-by: Ashish Kalra <ashish.kalra@xxxxxxx>
> ---
> drivers/crypto/ccp/sev-dev.c | 21 +++++++++++++--------
> 1 file changed, 13 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
> index 9632a9a5c92e..7c15dec55f58 100644
> --- a/drivers/crypto/ccp/sev-dev.c
> +++ b/drivers/crypto/ccp/sev-dev.c
> @@ -109,6 +109,13 @@ static void *sev_init_ex_buffer;
> */
> static struct sev_data_range_list *snp_range_list;
>
> +static int snp_shutdown_on_panic(struct notifier_block *nb,
> + unsigned long reason, void *arg);
> +
> +static struct notifier_block snp_panic_notifier = {
> + .notifier_call = snp_shutdown_on_panic,
> +};
> +
> static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
> {
> struct sev_device *sev = psp_master->sev_data;
> @@ -1191,6 +1198,9 @@ static int __sev_snp_init_locked(int *error)
> dev_info(sev->dev, "SEV-SNP API:%d.%d build:%d\n", sev->api_major,
> sev->api_minor, sev->build);
>
> + atomic_notifier_chain_register(&panic_notifier_list,
> + &snp_panic_notifier);
> +
> sev_es_tmr_size = SNP_TMR_SIZE;
>
> return 0;
> @@ -1751,6 +1761,9 @@ static int __sev_snp_shutdown_locked(int *error, bool panic)
> sev->snp_initialized = false;
> dev_dbg(sev->dev, "SEV-SNP firmware shutdown\n");
>
> + atomic_notifier_chain_unregister(&panic_notifier_list,
> + &snp_panic_notifier);
> +
> /* Reset TMR size back to default */
> sev_es_tmr_size = SEV_TMR_SIZE;
>
> @@ -2490,10 +2503,6 @@ static int snp_shutdown_on_panic(struct notifier_block *nb,
> return NOTIFY_DONE;
> }
>
> -static struct notifier_block snp_panic_notifier = {
> - .notifier_call = snp_shutdown_on_panic,
> -};
> -
> int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
> void *data, int *error)
> {
> @@ -2542,8 +2551,6 @@ void sev_pci_init(void)
> dev_info(sev->dev, "SEV%s API:%d.%d build:%d\n", sev->snp_initialized ?
> "-SNP" : "", sev->api_major, sev->api_minor, sev->build);
>
> - atomic_notifier_chain_register(&panic_notifier_list,
> - &snp_panic_notifier);
> return;
>
> err:
> @@ -2561,6 +2568,4 @@ void sev_pci_exit(void)
>
> sev_firmware_shutdown(sev);
>
> - atomic_notifier_chain_unregister(&panic_notifier_list,
> - &snp_panic_notifier);
> }
> --
> 2.34.1
>
Reviewed-by: Dionna Glaze <dionnaglaze@xxxxxxxxxx>
--
-Dionna Glaze, PhD, CISSP, CCSP (she/her)
