diff options
| -rw-r--r-- | kernel/gsp_sema_service.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/kernel/gsp_sema_service.c b/kernel/gsp_sema_service.c index 0e8474f..70c9d72 100644 --- a/kernel/gsp_sema_service.c +++ b/kernel/gsp_sema_service.c @@ -7802,6 +7802,22 @@ static int svc_copy_1d(struct nv_vgpu_device *vgpu, u64 dst, u64 src, size_t tot * kept the stale pre-pin pages while the copy landed on the pinned * page (streams2 r254: the b1 rec range carried the a2 pages and * the vadd read a2's pattern as its second input). + * + * r627: NEVER overwrite a per-page landing the loop above already + * stored. That loop stores each page's true resolved PA; this + * pass's `dst + po` is a contiguity guess valid only while the VA + * range maps contiguously. For a scattered UVM host buffer (r623c + * saxpy: page 0 at pa 0x115781000, page 0x7f000 at pa 0x12e700000) + * the guess clobbered the true entries - + * `sema-ledger: rewrite va=0x70e64e77f000 old=0x12e700000 + * new=0x115800000` - and the NEXT copy of the same VA then + * followed the poisoned ledger: 504x `sema-ledger: DIVERGE write + * va=0x70e64e7xxxxx prev=0x1158xxxxx cur=0x12e7xxxxx`; the + * non-pin branch keeps the ledger, so ~2 MiB of client c-data + * landed in guest pages the kernel had since re-used and the + * guest died in kchannelGetGfid_IMPL (r623c panic). The loop's + * per-page entries are the authority; this pass only seeds pages + * the loop did not reach. */ if (!dst_phys && dst_virt && dst_orig >= SVC_VAS_FLOOR && total >= (64u << 10)) { @@ -7809,8 +7825,14 @@ static int svc_copy_1d(struct nv_vgpu_device *vgpu, u64 dst, u64 src, size_t tot SVC_APERTURE_FB : SVC_APERTURE_SYS; size_t po; - for (po = 0; po < total; po += SEMA_PAGE_SIZE) + for (po = 0; po < total; po += SEMA_PAGE_SIZE) { + u64 lpa = 0; + u32 lap = 0; + + if (!svc_ledger_lookup(dst_orig + po, &lpa, &lap)) + continue; svc_ledger_store(dst_orig + po, dst + po, cap); + } } if (snap) svc_copy_snap_free(dst_orig, src_orig, total, owner_ch, |