diff options
Diffstat (limited to 'kernel/gsp_sema_service.c')
| -rw-r--r-- | kernel/gsp_sema_service.c | 289 |
1 files changed, 277 insertions, 12 deletions
diff --git a/kernel/gsp_sema_service.c b/kernel/gsp_sema_service.c index b90c948..ea96595 100644 --- a/kernel/gsp_sema_service.c +++ b/kernel/gsp_sema_service.c @@ -420,6 +420,18 @@ struct svc_channel { u64 gr_nocap_va; /* push VA the window was opened for */ unsigned long gr_nocap_since; /* absolute first-seen stamp */ /* + * r471: the completion-counter publish must never advance the + * guest's word past a push whose content was still unwritten when + * the entry was consumed (the streams_events staging-reuse + * corruption: the publish satisfied the client's D2H wait before + * its copy ran, and the readback drained a staging buffer that + * still held the PREVIOUS copy's bytes). Lowest ring slot consumed + * with all-zero content; 0 = none. Cleared when a later decode of + * a GR push reads non-zero content (the content landed - the rewinds + * re-read entries constantly, so this heals within a pass or two). + */ + u32 gr_bad_put; + /* * STALLFREE r225: stale-epoch / stale-replay wedge watchdog. A * channel that cannot make forward progress (last_get pinned behind * put, or a residual session put that never drops) is detected here @@ -486,6 +498,12 @@ struct svc_vaspace { u64 pdb; u32 entries; /* root entry count */ int ap; /* SVC_APERTURE_* of the directory itself */ + unsigned long stamp; /* r459: last registration/use; LRU evict + * when the table is full (a stale entry from + * a dead client otherwise blocks every new + * client after the 8th registration: the + * mid-boot walk failure that made the 10th+ + * client's copies fail rc=-2) */ }; struct svc_lat { @@ -819,6 +837,7 @@ struct sema_svc { u64 pushtrace_all; /* fail4: de-windowed push decode * trace (every push, bounded) */ u64 opadd_log; /* fail4: every op appended */ + u64 op2d_raw_log; /* r458: raw 2D-shaped copy pushes */ u64 dmatrace_log; /* fail4: denied-transfer trace */ u64 pend_dbg_log; /* fail4 r305: pending/hold witness */ u64 snap_gate_log; /* fail4 r311: capture-gate witness */ @@ -1599,12 +1618,40 @@ void gsp_sema_service_vaspace_add(const struct sema_vaspace_desc *desc) if (!vs && !svc.vas[i].valid) vs = &svc.vas[i]; } + /* + * r459: the table is 8 slots and the guest driver does not always + * send a teardown for a client's VA space (observed: 23 distinct + * registrations, 0 drops in one boot). Once all slots hold a dead + * client's directory, a NEW client's registration found no slot and + * every walk of its VAs failed (copies rc=-2, launches reading + * stale pages - the 10th-client mid-boot degradation). Evict the + * least-recently-registered entry instead of refusing the new one; + * the old client is gone and its directory pointer is dead guest + * memory, so the eviction can only remove stale authority. + */ + if (!vs) { + unsigned long oldest = 0; + int oi = 0; + + for (i = 0; i < SVC_MAX_VASPACES; i++) { + if (!svc.vas[i].valid) + continue; + if (!oldest || time_before(svc.vas[i].stamp, oldest)) { + oldest = svc.vas[i].stamp; + oi = i; + } + } + vs = &svc.vas[oi]; + pr_info("sema-svc: VA space table full; evicting 0x%x (pdb=0x%llx) for 0x%x\n", + vs->h_vaspace, vs->pdb, desc->h_vaspace); + } if (vs) { vs->valid = true; vs->h_vaspace = desc->h_vaspace; vs->pdb = desc->pdb; vs->entries = desc->num_entries; vs->ap = desc->b_vidmem ? SVC_APERTURE_FB : SVC_APERTURE_SYS; + vs->stamp = jiffies; /* A new directory invalidates what we learned from the old one. */ memset(svc.lat, 0, sizeof(svc.lat)); } @@ -1932,6 +1979,26 @@ static int svc_walk_vaspaces(struct nv_vgpu_device *vgpu, u64 va, } spin_unlock_irqrestore(&svc.vas_lock, flags); + /* + * r459: try the NEWEST registration first. A dead client's stale + * directory (the table outlives clients; only 8 slots) can still + * resolve a VA - through guest memory the driver has since reused - + * to a wrong page, and the first success wins. Ordering by the + * registration stamp makes the live client's directory the + * authority and only falls through to older ones when it cannot + * answer. + */ + for (i = 1; i < n; i++) { + struct svc_vaspace k = local[i]; + int j = i - 1; + + while (j >= 0 && time_before(local[j].stamp, k.stamp)) { + local[j + 1] = local[j]; + j--; + } + local[j + 1] = k; + } + for (i = 0; i < n; i++) { int alt; @@ -5997,14 +6064,18 @@ static void svc_copy_snap_free(u64 dst, u64 src, size_t total, } /* - * r444: drop every snapshot still owned by one entry. A snapshot that was - * not consumed by the entry's own copy execution (the copy ran via the - * forwarded hardware path, or a post-execution re-decode re-captured the - * unchanged staging) has no future consumer once the entry's release is - * delivered - leaving it behind let a LATER entry whose copy shares the - * (dst,src,total) triple execute from the stale bytes. + * r456/r457: the snapshot lifecycle is capture-once -> free on the copy's + * own successful consumption (svc_copy) -> free on ring-slot reuse with a + * new push hash (svc_copy_snap_capture) -> free when a re-decode skips an + * already-done op (svc_run_ops) -> TTL. The old per-entry owner free was + * removed from every opdef_clear caller: an entry whose release was + * delivered can still be REPLAYED (the pin-batch rewind) with its copy + * still owed, and freeing at that point let the replay re-capture the + * driver's refilled ping-pong staging (the r457 mode-C b1 H2D wrote b2's + * bytes into db1). A stale snapshot can only ever serve its own + * (ch, idx, hash) owner, so the r444 cross-entry poisoning stays closed. */ -static void svc_copy_snap_free_owner(u32 owner_ch, u32 owner_idx) +static void __maybe_unused svc_copy_snap_free_owner(u32 owner_ch, u32 owner_idx) { u32 i; @@ -6032,6 +6103,24 @@ static void svc_copy_snap_capture(struct nv_vgpu_device *vgpu, u64 dst, if (svc_copy_snap_lookup(dst, src, total, owner_ch, owner_idx, owner_hash)) return; /* already captured */ + /* + * r456: evict any snapshot left by the SAME ring slot under a + * DIFFERENT push hash (the slot was reused by a fresh push). The + * surviving-across-retries snapshot (svc_opdef_clear APPLY no + * longer frees it) must never be readable by the next occupant of + * the slot; the pass hash changes whenever the guest rewrites the + * push, so a same-slot different-hash snapshot is by definition + * stale for the new push. + */ + for (i = 0; i < SVC_COPY_SNAP_N; i++) { + if (svc_copy_snaps[i].buf && + svc_copy_snaps[i].owner_ch == owner_ch && + svc_copy_snaps[i].owner_idx == owner_idx && + svc_copy_snaps[i].owner_hash != owner_hash) { + kfree(svc_copy_snaps[i].buf); + svc_copy_snaps[i].buf = NULL; + } + } for (i = 0; i < SVC_COPY_SNAP_N; i++) { if (!svc_copy_snaps[i].buf) { s = &svc_copy_snaps[i]; @@ -7452,6 +7541,18 @@ svc_wait_done: */ if (ops_done && seq < 64 && ((*ops_done >> seq) & 1)) { svc.ops_once_skipped++; + /* + * r456: this op already ran in an earlier pass. Any + * staging snapshot a later re-decode pass re-captured + * for it (the capture sites run on every decode) is + * a leak that the r444 APPLY-free used to sweep; with + * that free removed (r456 keeps the snapshot alive + * across retries) drop it here so it can never serve + * a re-push of the ring slot. + */ + if (m->type == 1 && m->bytes <= SVC_COPY_SNAP_MAX) + svc_copy_snap_free(m->dst, m->src, m->bytes, + ch_h, entry_idx, pass_hash); continue; } @@ -9873,6 +9974,23 @@ static void svc_decode_stream(struct nv_vgpu_device *vgpu, const u8 *buf, break; case CE_M_LINE_LENGTH_IN: st.line_length = v0; + /* + * r458 THE memset2d root cause: the driver encodes + * LINE_LENGTH_IN (0x418) and the adjacent LINE_COUNT + * (0x41c) as ONE count=2 method group - observed raw + * push bytes `20028106 00001000 00000100` = header + * (subch 4, count 2, addr 0x418), line length 4096, + * line count 0x100 = 256. Reading only v0 left + * line_count = 0, so the 2D-copy builder below took + * the single-row path: one 4 KB op per push, and a + * 4 MB cudaMemcpy2D delivered exactly one page per + * 1 MB block (memset2d probe: per-MB ok=4096, + * bad=12.5M/12.58M). The GRCE variant below has + * always decoded the count=2 form; the CE path did + * not. + */ + if (count >= 2) + st.line_count = v1; break; /* r402: 2D geometry (cudaMemset2D / cudaMemcpy2D). */ case CE_M_LINE_COUNT: @@ -10180,6 +10298,39 @@ static void svc_decode_stream(struct nv_vgpu_device *vgpu, const u8 *buf, m->spitch = spitch; } } + /* + * r458 memset2d forensics: the + * driver's cudaMemcpy2D pushes decode + * LINE_LENGTH=4096 with PITCH_IN/OUT + * present but LINE_COUNT absent + * (lc=0), so only one 4 KB row per + * push executes and a 4 MB copy + * delivers 4 pages. Dump the raw push + * (bounded) for every pitch-shaped + * copy so the method stream that + * carries the row count is on record. + */ + if (gsp_sema_dbg && + (st.have_pitch_out || + st.have_pitch_in) && + svc.op2d_raw_log < 12) { + u32 dl = len < 220 ? len : 220; + + svc.op2d_raw_log++; + pr_info("sema-op2d-raw: h=0x%x push=0x%llx len=%u off=0x%x line=%u lc=%u po=%u/%u pi=%u/%u out=0x%llx in=0x%llx bytes=%u dma=0x%08x\n", + ch->h_object, push_va, + len, off, + st.line_length, + st.line_count, + st.have_pitch_out, + st.pitch_out, + st.have_pitch_in, + st.pitch_in, + m->dst, m->src, + (u32)m->bytes, dma); + pr_info("sema-op2d-raw: raw %*phN\n", + dl, buf); + } n_ops++; ops_seq++; } else if (gsp_sema_dbg && svc.dma_skip_log < 32) { @@ -14958,6 +15109,25 @@ static void svc_counter_publish(struct nv_vgpu_device *vgpu, return; val = put; + /* + * r471: never advance the guest's completion word past a push whose + * content was still unwritten when its entry was consumed. The + * clamp position is the lowest all-zero GR slot (gr_bad_put = slot + * + 1; 0 = none). Without it the publish can satisfy a D2H wait + * before its copy ran and the client drains a reused staging buffer + * holding the previous copy's bytes (streams_events h_c[2] = c0). + * The clamp heals when the rewinds re-read the slot with real + * content; the real completions still arrive through the decoded + * releases. + */ + if (!ch->engine_type && ch->gr_bad_put && val >= ch->gr_bad_put) { + val = ch->gr_bad_put - 1; + if (gsp_sema_dbg && svc.counter_pub_dbg < 96) { + svc.counter_pub_dbg++; + pr_info("sema-diag: pub-clamp h=0x%x pa=0x%llx val=%u (bad=%u) cur=%u\n", + ch->h_object, pa, val, ch->gr_bad_put, cur); + } + } if (val == ch->counter_last) return; /* @@ -15876,10 +16046,29 @@ static void svc_opdef_clear(struct svc_opdef_ent *e, u32 caller) e->n ? e->rel[0].va : 0ull, e->n ? e->rel[0].payload : 0u); } - /* r444: the entry is being consumed; no retry can need its - * staging snapshot any more (see svc_copy_snap_free_owner). */ - if (e->active) - svc_copy_snap_free_owner(e->h_object, e->entry_idx); + /* + * r456/r457: the snapshot lifecycle is now "capture once, consume + * on the copy's success, evict on ring-slot reuse, TTL". Every + * opdef_clear caller can still re-decode the entry: + * - APPLY (0): the pass's own op execution (which consumes the + * snapshot on success) follows the apply; + * - FINISH (1): the entry can be REPLAYED after a consume (the + * pin-batch rewind replays entries while mappings stream in), + * and an owed copy still needs the pipeline-order bytes; + * - FLUSH (2): the op stays skipped this pass but a later replay + * may run it. + * The r457 mode-C evidence: the b1 H2D's snapshot was captured at + * 191607.816388 with b1's bytes (first4=00000000 3e800000 ...), + * FINISH freed it on the entry's consume, the rewind replay + * re-captured at 191608.798838 from the REFILLED staging + * (first4=00000000 3d800000 ... = b2) and the deferred execution + * wrote b2's bytes into db1 (dst16_after=000000000000803d...). + * The r444 leak the old free guarded against is already covered + * by the owner key (a stale snapshot can only ever serve its own + * (ch, idx, hash)), the slot-reuse eviction in + * svc_copy_snap_capture, the ops_done skip free in svc_run_ops + * and the 30 s TTL. + */ memset(e, 0, sizeof(*e)); } @@ -21309,10 +21498,81 @@ static void svc_pump_channels(struct nv_vgpu_device *vgpu) * through to the historical * consume so the channel can * never livelock. + * + * r470: an ALL-ZERO push page is + * the same "not the client's work + * yet" condition - the ring entry + * is written (the previous + * session's or the client's own + * slot reuse) but the push + * CONTENT has not landed, so the + * decode sees no QMD and the + * entry would be consumed as a + * no-op; the end-of-pass counter + * publish then advances the + * guest's completion word while + * the real push was never read, + * and the client drains a + * staging buffer that still holds + * the PREVIOUS copy's bytes + * (streams_events: h_c[2] = c0 + * because the c2 D2H's + * completion was published 4.5 s + * before its copy ran, the ring + * slots having been decoded as + * all-zero pushes). Deliberately + * NARROWER than the CE-shaped + * plausibility verdict: compute + * pushes legitimately fail that + * matcher, so only an entirely + * zero page counts as unwritten. */ + { + bool all_zero = false; + + if (!ch->engine_type && + va && len) { + u32 zi; + + all_zero = true; + for (zi = 0; zi < len; + zi++) + if (pb[zi]) { + all_zero = + false; + break; + } + } + /* + * r471: publish clamp bookkeeping. + * A zero-content GR entry that is + * held or consumed must never let + * the end-of-pass counter publish + * advance the guest's completion + * word past it (the client would + * satisfy its readback wait before + * the real push/copy ran - the + * staging buffer still holds the + * previous copy's bytes). Record + * the lowest zero slot; a decode + * that reads non-zero content + * clears the clamp. + */ + if (!ch->engine_type) { + if (all_zero) { + if (!ch->gr_bad_put || + (u32)idx + 1 < + ch->gr_bad_put) + ch->gr_bad_put = + (u32)idx + 1; + } else if (va && len) { + ch->gr_bad_put = 0; + } + } if (!ch->engine_type && va && len && gsp_phys_gr_forward_enabled() && - svc_gr_qmd_seen > 0 && + (svc_gr_qmd_seen > 0 || + all_zero) && !entry_replay && !(svc_gr_cand.valid && svc_gr_cand.h_object == @@ -21364,6 +21624,7 @@ static void svc_pump_channels(struct nv_vgpu_device *vgpu) ch->h_object, (u32)idx, va, len); } + } /* * A CE push that should carry this * channel's next tracking release but @@ -22099,6 +22360,10 @@ static void svc_pump_channels(struct nv_vgpu_device *vgpu) svc.chan[k].push_hold_until = ch->push_hold_until; svc.chan[k].defer_since = ch->defer_since; svc.chan[k].put_prev = ch->put_prev; + /* r471: the publish clamp watermark is set + * and cleared on the pump thread; persist it + * so the next pass still clamps. */ + svc.chan[k].gr_bad_put = ch->gr_bad_put; /* * Persist the cheap-wait window and the content * watermark: the pump works on a snapshot, so |