On Wed, Aug 31, 2022 at 02:55:52AM +0000, Huang, Kai wrote: > On Wed, 2022-08-31 at 05:44 +0300, jarkko@xxxxxxxxxx wrote: > > On Wed, Aug 31, 2022 at 02:35:53AM +0000, Huang, Kai wrote: > > > On Wed, 2022-08-31 at 05:15 +0300, jarkko@xxxxxxxxxx wrote: > > > > On Wed, Aug 31, 2022 at 01:27:58AM +0000, Huang, Kai wrote: > > > > > On Tue, 2022-08-30 at 15:54 -0700, Reinette Chatre wrote: > > > > > > Hi Jarkko, > > > > > > > > > > > > On 8/29/2022 8:12 PM, Jarkko Sakkinen wrote: > > > > > > > In sgx_init(), if misc_register() for the provision device fails, and > > > > > > > neither sgx_drv_init() nor sgx_vepc_init() succeeds, then ksgxd will be > > > > > > > prematurely stopped. > > > > > > > > > > > > I do not think misc_register() is required to fail for the scenario to > > > > > > be triggered (rather use "or" than "and"?). Perhaps just > > > > > > "In sgx_init(), if a failure is encountered after ksgxd is started > > > > > > (via sgx_page_reclaimer_init()) ...". > > > > > > > > > > IMHO "a failure" might be too vague. For instance, failure to sgx_drv_init() > > > > > won't immediately result in ksgxd to stop prematurally. As long as KVM SGX can > > > > > be initialized successfully, sgx_init() still returns 0. > > > > > > > > > > Btw I was thinking whether we should move sgx_page_reclaimer_init() to the end > > > > > of sgx_init(), after we make sure at least one of the driver and the KVM SGX is > > > > > initialized successfully. Then the code change in this patch won't be necessary > > > > > if I understand correctly. AFAICT there's no good reason to start the ksgxd at > > > > > early stage before we are sure either the driver or KVM SGX will work. > > > > > > > > I would focus fixing the existing flow rather than reinventing the flow. > > > > > > > > It can be made to work, and therefore it is IMHO correct action to take. > > > > > > From another perspective, the *existing flow* is the reason which causes this > > > bug. A real fix is to fix the flow itself. > > > > Any existing flow in part of the kernel can have a bug. That > > does not mean that switching flow would be proper way to fix > > a bug. > > > > BR, Jarkko > > Yes but I think this is only true when the flow is reasonable. If the flow > itself isn't reasonable, we should fix the flow (given it's easy to fix AFAICT). > > Anyway, let us also hear from others. The flow can be made to work without issues, which in the context of a bug fix is exactly what a bug fix should do. Not more or less. You don't gain any measurable value for the user with this switch idea. BR, Jarkko
