[intel-sgx-kernel-dev,1/3] intel_sgx: do not use BUG() in sgx_free_page()
diff mbox

Message ID 20170126212038.12809-2-jarkko.sakkinen@linux.intel.com
State New
Headers show

Commit Message

Jarkko Sakkinen Jan. 26, 2017, 9:20 p.m. UTC
EREMOVE fails on non-EPC page or when a SECS page with children is to be
removed. These do not happen if the driver is working correctly. Log the
error but do not crash the driver.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/platform/x86/intel_sgx_page_cache.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

Comments

Jarkko Sakkinen Jan. 27, 2017, 6:28 a.m. UTC | #1
Please comment the other copy.

/Jarkko

On Thu, Jan 26, 2017 at 11:20:36PM +0200, Jarkko Sakkinen wrote:
> EREMOVE fails on non-EPC page or when a SECS page with children is to be
> removed. These do not happen if the driver is working correctly. Log the
> error but do not crash the driver.
> 
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> ---
>  drivers/platform/x86/intel_sgx_page_cache.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/platform/x86/intel_sgx_page_cache.c b/drivers/platform/x86/intel_sgx_page_cache.c
> index d073057..7f73ac7 100644
> --- a/drivers/platform/x86/intel_sgx_page_cache.c
> +++ b/drivers/platform/x86/intel_sgx_page_cache.c
> @@ -551,10 +551,8 @@ void sgx_free_page(struct sgx_epc_page *entry,
>  		ret = __eremove(epc);
>  		sgx_put_epc_page(epc);
>  
> -		if (ret) {
> -			pr_err("EREMOVE returned %d\n", ret);
> -			BUG();
> -		}
> +		if (ret)
> +			sgx_err(encl, "EREMOVE returned %d\n", ret);
>  	}
>  
>  	spin_lock(&sgx_free_list_lock);
> -- 
> 2.9.3
>
Jarkko Sakkinen Jan. 29, 2017, 3:11 p.m. UTC | #2
On Fri, Jan 27, 2017 at 05:45:03PM +0200, Andy Shevchenko wrote:
> On Thu, Jan 26, 2017 at 11:20 PM, Jarkko Sakkinen
> <jarkko.sakkinen@linux.intel.com> wrote:
> > EREMOVE fails on non-EPC page or when a SECS page with children is to be
> > removed. These do not happen if the driver is working correctly. Log the
> > error but do not crash the driver.
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > ---
> >  drivers/platform/x86/intel_sgx_page_cache.c | 6 ++----
> >  1 file changed, 2 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/platform/x86/intel_sgx_page_cache.c b/drivers/platform/x86/intel_sgx_page_cache.c
> > index d073057..7f73ac7 100644
> > --- a/drivers/platform/x86/intel_sgx_page_cache.c
> > +++ b/drivers/platform/x86/intel_sgx_page_cache.c
> > @@ -551,10 +551,8 @@ void sgx_free_page(struct sgx_epc_page *entry,
> >                 ret = __eremove(epc);
> >                 sgx_put_epc_page(epc);
> >
> > -               if (ret) {
> > -                       pr_err("EREMOVE returned %d\n", ret);
> > -                       BUG();
> > -               }
> > +               if (ret)
> > +                       sgx_err(encl, "EREMOVE returned %d\n", ret);
> 
> Do you have something like critical level? For me seems reasonable to
> increase the level of message if BUG() was somehow related to actual
> situation.

Hmm... I think that would make sense. This could only happen when
the driver implementation is working incorrectly.

/Jarkko

Patch
diff mbox

diff --git a/drivers/platform/x86/intel_sgx_page_cache.c b/drivers/platform/x86/intel_sgx_page_cache.c
index d073057..7f73ac7 100644
--- a/drivers/platform/x86/intel_sgx_page_cache.c
+++ b/drivers/platform/x86/intel_sgx_page_cache.c
@@ -551,10 +551,8 @@  void sgx_free_page(struct sgx_epc_page *entry,
 		ret = __eremove(epc);
 		sgx_put_epc_page(epc);
 
-		if (ret) {
-			pr_err("EREMOVE returned %d\n", ret);
-			BUG();
-		}
+		if (ret)
+			sgx_err(encl, "EREMOVE returned %d\n", ret);
 	}
 
 	spin_lock(&sgx_free_list_lock);