6.6-stable review patch. If anyone has any objections, please let me know.
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From: Pavan Kumar Paluri papaluri@amd.com
commit ce3d2d6b150ba8528f3218ebf0cee2c2c572662d upstream.
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@vger.kernel.org Signed-off-by: Pavan Kumar Paluri papaluri@amd.com Acked-by: Tom Lendacky thomas.lendacky@amd.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/crypto/ccp/sev-dev.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/drivers/crypto/ccp/sev-dev.c +++ b/drivers/crypto/ccp/sev-dev.c @@ -1367,6 +1367,8 @@ void sev_pci_init(void) return;
err: + sev_dev_destroy(psp_master); + psp_master->sev_data = NULL; }