> -----Original Message----- > From: Christian König <ckoenig.leichtzumerken@xxxxxxxxx> > Sent: Thursday, July 18, 2019 3:14 AM > To: Kuehling, Felix <Felix.Kuehling@xxxxxxx>; Greathouse, Joseph > <Joseph.Greathouse@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH v2] drm/amdgpu: Default disable GDS for compute > VMIDs > > Am 17.07.19 um 22:09 schrieb Kuehling, Felix: > > On 2019-07-17 14:23, Greathouse, Joseph wrote: > >> The GDS and GWS blocks default to allowing all VMIDs to > >> access all entries. Graphics VMIDs can handle setting > >> these limits when the driver launches work. However, > >> compute workloads under HWS control don't go through the > >> kernel driver. Instead, HWS firmware should set these > >> limits when a process is put into a VMID slot. > >> > >> Disable access to these devices by default by turning off > >> all mask bits (for OA) and setting BASE=SIZE=0 (for GDS > >> and GWS) for all compute VMIDs. If a process wants to use > >> these resources, they can request this from the HWS > >> firmware (when such capabilities are enabled). HWS will > >> then handle setting the base and limit for the process when > >> it is assigned to a VMID. > >> > >> This will also prevent user kernels from getting 'stuck' in > >> GWS by accident if they write GWS-using code but HWS > >> firmware is not set up to handle GWS reset. Until HWS is > >> enabled to handle GWS properly, all GWS accesses will > >> MEM_VIOL fault the kernel. > >> > >> v2: Move initialization outside of SRBM mutex > >> > >> Change-Id: I8edcea9d0b14d16a7444bcf9fbf9451aef8b707d > >> Signed-off-by: Joseph Greathouse <Joseph.Greathouse@xxxxxxx> > > Reviewed-by: Felix Kuehling <Felix.Kuehling@xxxxxxx> > > Might be a good idea to do this for all VMIDs during initialization and > not just for the ones used for compute. > > But anyway patch is Reviewed-by: Christian König > <christian.koenig@xxxxxxx>. Hmm, good point. It looks like graphics jobs will eventually call through to emit_gds_switch() to set these when launching a job, but it may be worthwhile to set these to zero as a default. I didn't want to step on any toes on the graphics side without checking first. Do you have opinions on the most reasonable location to do this? early_init(), late_init()? The various gfx_v*_set_gds_init() might be a good place -- a quick test of setting all 16 VMIDs in gfx_v9_0_set_gds_init() appears to work fine on my Vega 20. -Joe _______________________________________________ amd-gfx mailing list amd-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/amd-gfx
