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.
