ppc/xive2: fix context push calculation of IPB priority

Pushing a context and loading IPB from NVP is defined to merge ('or')
that IPB into the TIMA IPB register. PIPR should therefore be calculated
based on the final IPB value, not just the NVP value.

Fixes: 9d2b6058c5b ("ppc/xive2: Add grouping level to notification")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Glenn Miles <milesg@linux.ibm.com>
Reviewed-by: Caleb Schlossin <calebs@linux.ibm.com>
Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Link: https://lore.kernel.org/qemu-devel/20250512031100.439842-6-npiggin@gmail.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
(cherry picked from commit d1023a296c8297454fc4b207d58707c0a5e62e0a)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

diff --git a/hw/intc/xive2.c b/hw/intc/xive2.c
index 790152a2a6611615088d19df7ebea9f8a1d284ff..4dd04a0398369cde6788963e0812cdaeb4295f12 100644 (file)
--- a/hw/intc/xive2.c
+++ b/hw/intc/xive2.c
@@ -835,8 +835,9 @@ static void xive2_tctx_need_resend(Xive2Router *xrtr, XiveTCTX *tctx,
         nvp.w2 = xive_set_field32(NVP2_W2_IPB, nvp.w2, 0);
         xive2_router_write_nvp(xrtr, nvp_blk, nvp_idx, &nvp, 2);
     }
+    /* IPB bits in the backlog are merged with the TIMA IPB bits */
     regs[TM_IPB] |= ipb;
-    backlog_prio = xive_ipb_to_pipr(ipb);
+    backlog_prio = xive_ipb_to_pipr(regs[TM_IPB]);
     backlog_level = 0;
 
     first_group = xive_get_field32(NVP2_W0_PGOFIRST, nvp.w0);