On 8/15/2024 7:25 AM, 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
>
> Call Trace:
> <TASK>
> dump_stack_lvl+0xd7/0xf0
> dump_stack+0x10/0x20
> sysfs_warn_dup+0x5c/0x70
> sysfs_create_dir_ns+0xbc/0xd
> kobject_add_internal+0xb1/0x2f0
> kobject_add+0x7a/0xe0
> ? srso_alias_return_thunk+0x5/0xfbef5
> ? get_device_parent+0xd4/0x1e0
> ? __pfx_klist_children_get+0x10/0x10
> device_add+0x121/0x870
> ? srso_alias_return_thunk+0x5/0xfbef5
> device_create_groups_vargs+0xdc/0x100
> device_create_with_groups+0x3f/0x60
> misc_register+0x13b/0x1c0
> sev_dev_init+0x1d4/0x290 [ccp]
> psp_dev_init+0x136/0x300 [ccp]
> sp_init+0x6f/0x80 [ccp]
> sp_pci_probe+0x2a6/0x310 [ccp]
> ? srso_alias_return_thunk+0x5/0xfbef5
> local_pci_probe+0x4b/0xb0
> work_for_cpu_fn+0x1a/0x30
> process_one_work+0x203/0x600
> worker_thread+0x19e/0x350
> ? __pfx_worker_thread+0x10/0x10
> kthread+0xeb/0x120
> ? __pfx_kthread+0x10/0x10
> ret_from_fork+0x3c/0x60
> ? __pfx_kthread+0x10/0x10
> ret_from_fork_asm+0x1a/0x30
> </TASK>
> kobject: kobject_add_internal failed for sev with -EEXIST, don't try to register things with the same name in the same directory.
> ccp 0000:22:00.1: sev initialization failed
> ccp 0000:22:00.1: psp initialization failed
> ccp 0000:a2:00.1: no command queues available
> ccp 0000:a2:00.1: psp enabled
>
> 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>
> ---
> drivers/crypto/ccp/sev-dev.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c
> index 9810edbb272d..5f63d2018649 100644
> --- a/drivers/crypto/ccp/sev-dev.c
> +++ b/drivers/crypto/ccp/sev-dev.c
> @@ -2410,6 +2410,8 @@ void sev_pci_init(void)
> return;
>
> err:
> + sev_dev_destroy(psp_master);
> +
> psp_master->sev_data = NULL;
> }
>
>
> base-commit: b8c7cbc324dc17b9e42379b42603613580bec2d8
A gentle reminder,
Thanks,
Pavan
