> -----Original Message----- > From: Wood Scott-B07421 > Sent: Wednesday, April 30, 2014 1:13 AM > To: Liu Gang-B34182 > Cc: linuxppc-dev@lists.ozlabs.org > Subject: Re: [PATCH] powerpc/fsl-rio: Fix fsl_rio_setup error paths and > use-after-unmap > > On Mon, 2014-04-28 at 23:04 -0500, Liu Gang-B34182 wrote: > > > -----Original Message----- > > > From: Wood Scott-B07421 > > > Sent: Tuesday, April 29, 2014 9:32 AM > > > To: linuxppc-dev@lists.ozlabs.org > > > Cc: Wood Scott-B07421; Liu Gang-B34182 > > > Subject: [PATCH] powerpc/fsl-rio: Fix fsl_rio_setup error paths and > > > use- after-unmap > > > > > > Several of the error paths from fsl_rio_setup are missing error > messages. > > > > > > Worse, fsl_rio_setup initializes several global pointers and does > > > not NULL them out after freeing/unmapping on error. This caused > > > fsl_rio_mcheck_exception() to crash when accessing rio_regs_win > > > which was non-NULL but had been unmapped. > > > > > > Signed-off-by: Scott Wood <scottw...@freescale.com> > > > Cc: Liu Gang <gang....@freescale.com> > > > --- > > > Liu Gang, are you sure all of these error conditions are fatal? Why > > > does the rio driver fail if rmu is not present (e.g. on t4240)? > > > > Hi Scott, I think the errors you modified in the patch are serious and > > should be fixed. Thanks very much! > > And in fact, the rio driver can be used just for the submodule of the > SRIO: RMU. > > It should be used with arch/powerpc/sysdev/fsl_rmu.c and there should > > have the RMU module. > > The fsl_rio.c implements some basic and needed works to support the RMU > running well. > > I don't quite follow -- is it expected that rio can work without rmu, or > not? As is, fsl_rio_setup() will error out if it doesn't find an > fsl,srio-rmu-handle property.
fsl_rio_setup() doesn't expect that rio can work without rmu. All the rio drivers just has one purpose, it's rmu. But rmu is a submodule of the rio, so the driver should parse rio in dtb and finish some initial works first, and then to setup rmu. That's why the drivers cannot just have a such as rmu_setup() to parse fsl,srio-rmu-handle property. Thanks, Liu Gang _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
