CVS commit: src/sys/uvm

[Taylor R Campbell]

Module Name:    src
Committed By:   riastradh
Date:           Sat Jun  4 20:54:24 UTC 2022

Modified Files:
        src/sys/uvm: uvm_map.c

Log Message:
uvm(9): Fix 19-year-old bug in assertion about mmap hint.

Previously this would _first_ remember the original hint, and _then_
clamp the hint to the VM map's range:

        orig_hint = hint;
        if (hint < vm_map_min(map)) {   /* check ranges ... */
                if (flags & UVM_FLAG_FIXED) {
                        UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0);
                        return (NULL);
                }
                hint = vm_map_min(map);
        ...
        KASSERTMSG(!topdown || hint <= orig_hint, "hint: %#jx, orig_hint: %#jx",
            (uintmax_t)hint, (uintmax_t)orig_hint);

Even if nothing else happens in the ellipsis, taking the branch
guarantees the assertion will fail in the topdown case.


To generate a diff of this commit:
cvs rdiff -u -r1.394 -r1.395 src/sys/uvm/uvm_map.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.