The branch main has been updated by jhibbits:

URL: 
https://cgit.FreeBSD.org/src/commit/?id=dec79d2b47b3cb797d45b8bee7a1640dec85ebcc

commit dec79d2b47b3cb797d45b8bee7a1640dec85ebcc
Author:     Justin Hibbits <[email protected]>
AuthorDate: 2026-07-05 23:03:31 +0000
Commit:     Justin Hibbits <[email protected]>
CommitDate: 2026-07-06 21:23:55 +0000

    powerpc/pmap(booke): Fix TLB TID eviction
    
    Fix tid_set_busy() for when `pmap` is NULL. Obviously a NULL pointer
    cannot be correctly used, so I'm not sure how it worked in testing on
    64-bit.
---
 sys/powerpc/booke/pmap.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/sys/powerpc/booke/pmap.c b/sys/powerpc/booke/pmap.c
index 310d38d5c450..545416921d09 100644
--- a/sys/powerpc/booke/pmap.c
+++ b/sys/powerpc/booke/pmap.c
@@ -2484,11 +2484,14 @@ mmu_booke_page_array_startup(long pages)
 static __inline void
 tid_set_busy(int cpu, int tid, pmap_t pmap)
 {
-       tidbusy[cpu * (tid_max + 1) + tid] = pmap;
-       if (pmap == NULL)
-               pmap->pm_tid[cpu] = TID_NONE;
-       else
+       volatile pmap_t *pm = &tidbusy[cpu * (tid_max + 1) + tid];
+
+       if (pmap == NULL) {
+               if (*pm != NULL)
+                       (*pm)->pm_tid[cpu] = TID_NONE;
+       } else
                pmap->pm_tid[cpu] = tid;
+       *pm = pmap;
 }
 
 static __inline pmap_t
@@ -2522,7 +2525,7 @@ tid_alloc(pmap_t pmap)
        /* If we are stealing TID then clear the relevant pmap's field */
        if (tid_get_busy(thiscpu, tid) != NULL) {
                CTR2(KTR_PMAP, "%s: warning: stealing tid %d", __func__, tid);
-               
+
                tid_set_busy(thiscpu, tid, NULL);
 
                /* Flush all entries from TLB0 matching this TID. */

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