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-rw-r--r--kernel/gsp_phys_booter.c21
1 files changed, 21 insertions, 0 deletions
diff --git a/kernel/gsp_phys_booter.c b/kernel/gsp_phys_booter.c
index b19fa0d..217f4e4 100644
--- a/kernel/gsp_phys_booter.c
+++ b/kernel/gsp_phys_booter.c
@@ -19897,6 +19897,27 @@ gr_page_unmapped:
/* A stale release from a previous submission must not be observed. */
WRITE_ONCE(*(u32 *)sem_va, 0);
WRITE_ONCE(*(u32 *)(sem_va + 4), 0);
+ /*
+ * r441: zero the GUEST-VISIBLE release words for the first attempt
+ * too, not only for outcome retries. The r439 evidence shows a first
+ * attempt whose poll broke on a STALE value (qmd_rel=0x00000005 from
+ * the previous launch's engine write, want=6) while the engine never
+ * fetched this launch's deposit (sentinel intact, "engine fetch
+ * NONE"): the host then shipped a completion for a launch that did
+ * not run. Zeroing forces the poll to wait for THIS launch's own
+ * engine write; when the engine does not write it, the timeout ladder
+ * and the software-authored completion take over (the honest path),
+ * and the wedge classification stops being satisfiable by a stale
+ * value. The write guard re-validates the target like the retry path.
+ */
+ if (qmd_rel_hpa && qmd_rel_off < GSP_PHYS_PAGE_SIZE &&
+ gsp_sema_gr_write_guard(req->rel_va, qmd_rel_hpa,
+ "gr-rel-zero-first"))
+ WRITE_ONCE(*(u32 *)((u8 *)__va(qmd_rel_hpa) + qmd_rel_off), 0);
+ if (ch_rel_hpa && ch_rel_off < GSP_PHYS_PAGE_SIZE &&
+ gsp_sema_gr_write_guard(req->rel_va, ch_rel_hpa,
+ "gr-chrel-zero-first"))
+ WRITE_ONCE(*(u32 *)((u8 *)__va(ch_rel_hpa) + ch_rel_off), 0);
wmb();
/*