From 38ba1e2d7d579c2467dfa10daca16cdbd6579089 Mon Sep 17 00:00:00 2001 From: Arthur Hanson Rasmusson Date: Tue, 27 Oct 2026 07:06:12 -0400 Subject: vgsp: channel-scoped VA resolution via the channel's own VAS (r835) Every RM client maps different objects at the same numeric VAs (all clients' windows sit at 0x1200xxxxx), so the global VA-keyed pin/lat/map layers conflate them across clients. Live walk_probe evidence (r834): the X server's ring VA 0x120090000 resolved through the GL client's page tables (vas h=0xcaf00005 -> a zero page) while the X client's own VAS (vas h=0x10005) holds the real page (pa=0x1294fa000). That conflation is what wedged the X server's readback wait and starved the RC watchdog's ring (its pushes decoded as empty). * Parse NV_CHANNEL_ALLOC_PARAMS.hVASpace (@28; layout confirmed by the struct's own known offsets) at channel registration and carry it on svc_channel. * svc_chanvas_lookup: resolve a VA through the serviced channel's own VAS page tables first (svc_cur_vas, refreshed per channel turn and in the decode path). The hook sits at the head of svc_lookup_trusted, so ring, push, release and notifier resolution all inherit it; a failed walk falls through to the old chain unchanged. Live r835: X's XShmGetImage readback, previously never completing, returned after its long wait and a frame reached the kvmfr BAR (first frame content still black and readback latency still ~87 s; the guest-side fbcopy_pub framebuffer reader tool is added for the direct-VRAM capture path, find/pub/test modes). --- kernel/gsp_sema_service.h | 1 + 1 file changed, 1 insertion(+) (limited to 'kernel/gsp_sema_service.h') diff --git a/kernel/gsp_sema_service.h b/kernel/gsp_sema_service.h index 94faf82..63c7f82 100644 --- a/kernel/gsp_sema_service.h +++ b/kernel/gsp_sema_service.h @@ -31,6 +31,7 @@ struct sema_channel_desc { u32 h_object; u32 engine_type; u32 cid; /* RM channel id (the doorbell token vector) */ + u32 h_vaspace; /* r835: VAS handle the channel was allocated in */ u64 gpfifo_va; u32 gpfifo_entries; u64 userd_pa; /* NvA06FControl: GPGet @0x88, GPPut @0x8c */ -- cgit v1.2.3