Message ID | 20131219231853.GB22418@oc3347516403.ibm.com (mailing list archive) |
---|---|
State | Superseded, archived |
Headers | show |
On Thu, Dec 19, 2013 at 05:18:53PM -0600, Brian W Hart wrote: >Prevent ioda_eeh_hub_diag() from clobbering itself when called by supplying >a buffer for P7IOC hub diagnostic data. Take care to inform OPAL of the >correct size for the buffer. > >Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com> >--- > >I hope I've understood this correctly. It looks to me like >ioda_eeh_hub_data is effectively asking OPAL to clobber its own >text (via 'data') when it makes the call to retrieve the hub data. > Yeah, we should have used following variable as HUB diag-data instead. static char *hub_diag = NULL; However, it's not safe to allocate page-sized buffer for "hub_diag". >Added a hub diagnostic structure per-phb. Perhaps the diagnostic >structure better belongs in the phb->diag union, but I wasn't sure whether >we'd need to carry the hub and PHB diag data at the same time. > Please put hub diag-data to struct pnv_phb::diag since we don't need carry hub and PHB diag-data at same time. With it, please remove variable "hub_diag" as well. > arch/powerpc/platforms/powernv/eeh-ioda.c | 4 ++-- > arch/powerpc/platforms/powernv/pci.h | 2 ++ > 2 files changed, 4 insertions(+), 2 deletions(-) > >diff --git a/arch/powerpc/platforms/powernv/eeh-ioda.c b/arch/powerpc/platforms/powernv/eeh-ioda.c >index 8184ef5..dfd9134 100644 >--- a/arch/powerpc/platforms/powernv/eeh-ioda.c >+++ b/arch/powerpc/platforms/powernv/eeh-ioda.c >@@ -636,8 +636,8 @@ static void ioda_eeh_hub_diag(struct pci_controller *hose) > struct OpalIoP7IOCErrorData *data; > long rc; > >- data = (struct OpalIoP7IOCErrorData *)ioda_eeh_hub_diag; >- rc = opal_pci_get_hub_diag_data(phb->hub_id, data, PAGE_SIZE); >+ data = (struct OpalIoP7IOCErrorData *)&phb->p7ioc_err; >+ rc = opal_pci_get_hub_diag_data(phb->hub_id, data, sizeof *data); > if (rc != OPAL_SUCCESS) { > pr_warning("%s: Failed to get HUB#%llx diag-data (%ld)\n", > __func__, phb->hub_id, rc); >diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h >index 911c24e..d1b6d8c 100644 >--- a/arch/powerpc/platforms/powernv/pci.h >+++ b/arch/powerpc/platforms/powernv/pci.h >@@ -177,6 +177,8 @@ struct pnv_phb { > unsigned char blob[PNV_PCI_DIAG_BUF_SIZE]; > struct OpalIoP7IOCPhbErrorData p7ioc; > } diag; >+ >+ struct OpalIoP7IOCErrorData p7ioc_err; > }; > > extern struct pci_ops pnv_pci_ops; Thanks, Gavin
On Fri, Dec 20, 2013 at 09:45:04AM +0800, Gavin Shan wrote: > On Thu, Dec 19, 2013 at 05:18:53PM -0600, Brian W Hart wrote: > >Prevent ioda_eeh_hub_diag() from clobbering itself when called by supplying > >a buffer for P7IOC hub diagnostic data. Take care to inform OPAL of the > >correct size for the buffer. > > > >Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com> > >--- > > > >I hope I've understood this correctly. It looks to me like > >ioda_eeh_hub_data is effectively asking OPAL to clobber its own > >text (via 'data') when it makes the call to retrieve the hub data. > > > > Yeah, we should have used following variable as HUB diag-data instead. > > static char *hub_diag = NULL; > > However, it's not safe to allocate page-sized buffer for "hub_diag". > > >Added a hub diagnostic structure per-phb. Perhaps the diagnostic > >structure better belongs in the phb->diag union, but I wasn't sure whether > >we'd need to carry the hub and PHB diag data at the same time. > > > > Please put hub diag-data to struct pnv_phb::diag since we don't need > carry hub and PHB diag-data at same time. With it, please remove > variable "hub_diag" as well. Thanks; will send another patch.
diff --git a/arch/powerpc/platforms/powernv/eeh-ioda.c b/arch/powerpc/platforms/powernv/eeh-ioda.c index 8184ef5..dfd9134 100644 --- a/arch/powerpc/platforms/powernv/eeh-ioda.c +++ b/arch/powerpc/platforms/powernv/eeh-ioda.c @@ -636,8 +636,8 @@ static void ioda_eeh_hub_diag(struct pci_controller *hose) struct OpalIoP7IOCErrorData *data; long rc; - data = (struct OpalIoP7IOCErrorData *)ioda_eeh_hub_diag; - rc = opal_pci_get_hub_diag_data(phb->hub_id, data, PAGE_SIZE); + data = (struct OpalIoP7IOCErrorData *)&phb->p7ioc_err; + rc = opal_pci_get_hub_diag_data(phb->hub_id, data, sizeof *data); if (rc != OPAL_SUCCESS) { pr_warning("%s: Failed to get HUB#%llx diag-data (%ld)\n", __func__, phb->hub_id, rc); diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h index 911c24e..d1b6d8c 100644 --- a/arch/powerpc/platforms/powernv/pci.h +++ b/arch/powerpc/platforms/powernv/pci.h @@ -177,6 +177,8 @@ struct pnv_phb { unsigned char blob[PNV_PCI_DIAG_BUF_SIZE]; struct OpalIoP7IOCPhbErrorData p7ioc; } diag; + + struct OpalIoP7IOCErrorData p7ioc_err; }; extern struct pci_ops pnv_pci_ops;
Prevent ioda_eeh_hub_diag() from clobbering itself when called by supplying a buffer for P7IOC hub diagnostic data. Take care to inform OPAL of the correct size for the buffer. Signed-off-by: Brian W Hart <hartb@linux.vnet.ibm.com> --- I hope I've understood this correctly. It looks to me like ioda_eeh_hub_data is effectively asking OPAL to clobber its own text (via 'data') when it makes the call to retrieve the hub data. Added a hub diagnostic structure per-phb. Perhaps the diagnostic structure better belongs in the phb->diag union, but I wasn't sure whether we'd need to carry the hub and PHB diag data at the same time. arch/powerpc/platforms/powernv/eeh-ioda.c | 4 ++-- arch/powerpc/platforms/powernv/pci.h | 2 ++ 2 files changed, 4 insertions(+), 2 deletions(-)