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Diffstat (limited to 'kernel/gsp_sema_service.c')
| -rw-r--r-- | kernel/gsp_sema_service.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/kernel/gsp_sema_service.c b/kernel/gsp_sema_service.c index e76cb7a..0e8474f 100644 --- a/kernel/gsp_sema_service.c +++ b/kernel/gsp_sema_service.c @@ -2696,8 +2696,23 @@ static bool svc_vas_has(u64 va) * 100 TiB). Explicit sources (GRCE inline writes, the bridge's output write) * shadow any VA because their target is device memory by construction. */ +bool gsp_sema_no_shadow; /* r626 A/B: disable the shadow lane */ +module_param_named(sema_no_shadow, gsp_sema_no_shadow, bool, 0644); +MODULE_PARM_DESC(sema_no_shadow, + "Disable the VA shadow lane (copy-dst and fill fallbacks) for an A/B boot; unresolved device VAs hold instead (default 0)"); + static bool svc_vas_can_shadow(u64 va) { + /* + * r626 A/B: with the knob set, every shadow fallback is refused and + * the caller takes its -ENOENT/hold path. The r613c/r616/r623c + * corruption class (nvidia channel structures overwritten with + * PTE-like 0x444../0x4456.. patterns, fatal panic in + * kchannelGetGfid_IMPL via nvGpuOpsStopChannel) follows the + * shadow-lane era; this knob isolates the lane as a variable. + */ + if (gsp_sema_no_shadow) + return false; return va >= SVC_VAS_FLOOR; } |