diff options
Diffstat (limited to 'kernel/gsp_phys_gpu.c')
| -rw-r--r-- | kernel/gsp_phys_gpu.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/kernel/gsp_phys_gpu.c b/kernel/gsp_phys_gpu.c index 9b7235b..72884b8 100644 --- a/kernel/gsp_phys_gpu.c +++ b/kernel/gsp_phys_gpu.c @@ -974,6 +974,44 @@ int gsp_phys_rmcall_gr_nowrite_retry_value(void) EXPORT_SYMBOL_GPL(gsp_phys_rmcall_gr_nowrite_retry_value); /* + * m156 fail-closed release gate (gsp_phys_rmcall_gr_failclosed; default 1). + * + * The engine's QMD/channel completion ack is a front-end retirement, not an + * execution witness: the r155 live log shows launches reporting + * qmd_rel=6/ch_rel=0xc0ffee02 with the retirement wait observing + * "0/205 pages changed" on the initial attempt and all three outcome + * retries, after which the backend returned success and the client + * (streams2) read all-zero output (STREAMS bad=32768) while the soft + * release machinery also authored the completion for never-attempted + * captures. For a data-bearing launch (resolved operand pages exist) the + * completion release must therefore be host-owned and gated on an observed + * engine write: + * + * - release0 is routed to the module semaphore (the m64 rel-mod shape) so + * the engine's ack cannot reach the guest's release word; + * - the backend returns an error (not success) when the retirement wait + * still saw zero writes after the bounded retries, so the sema service + * holds the guest release instead of authoring it; + * - the sema service delivers a channel error for the withheld release so + * the client observes a launch failure, never stale/zero data as + * success. + * + * Set to 0 to restore the historical fail-open behavior (engine-authored + * release, success returned regardless of writes). + */ +static int gsp_phys_rmcall_gr_failclosed_param = 1; +module_param_named(gsp_phys_rmcall_gr_failclosed, + gsp_phys_rmcall_gr_failclosed_param, int, 0644); +MODULE_PARM_DESC(gsp_phys_rmcall_gr_failclosed, + "Withhold a data-bearing forwarded GR launch's completion release unless the engine wrote data (default 1 = fail closed)"); + +int gsp_phys_rmcall_gr_failclosed_value(void) +{ + return gsp_phys_rmcall_gr_failclosed_param; +} +EXPORT_SYMBOL_GPL(gsp_phys_rmcall_gr_failclosed_value); + +/* * m69 window-0 shadow pool (gsp_phys_rmcall_gr_shadow_win0; default 0). When * set, the forwarded GR launch copies the QMD's program/param pages into the * window-0 shadow pool (module pages at VAs 0x108000..0x10f000, PTEs planted |