CVS commit: [netbsd-9] src/sys/arch/powerpc/ibm4xx

["Martin Husemann" <martin%netbsd.org@localhost>]

Module Name:    src
Committed By:   martin
Date:           Thu Feb 27 18:23:10 UTC 2020

Modified Files:
        src/sys/arch/powerpc/ibm4xx [netbsd-9]: pmap.c

Log Message:
Pull up following revision(s) (requested by rin in ticket #731):

        sys/arch/powerpc/ibm4xx/pmap.c: revision 1.80
        sys/arch/powerpc/ibm4xx/pmap.c: revision 1.77
        sys/arch/powerpc/ibm4xx/pmap.c: revision 1.78
        sys/arch/powerpc/ibm4xx/pmap.c: revision 1.79

Fix NULL dereference; "pap" argument of pmap_extract(9) can be NULL.

 -

Fix off-by-one error for ctx (ASID).

 -

Note that NUM_CTX = 256 = 0 stands for disabling protection by ASID.
Clear ti_ctx when flushing a TLB entry for clarity.

 -

In ppc4xx_tlb_find_victim(), mark kernel stack page TLBF_REF instead of
TLBF_USED. This should be originally intended behavior of this code
segment, because
- TLBF_USED is already checked just before, so marking this page
  TLBF_USED is no-op.
- TLBF_REF flag exempts that page from being flushed from TLB in next
  scan, when kernel stack may be still there with high probability.


To generate a diff of this commit:
cvs rdiff -u -r1.76 -r1.76.20.1 src/sys/arch/powerpc/ibm4xx/pmap.c

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